This is exactly the video I've been looking for and precisely the kind of amp I want to build. I really appreciate this video. Thank you Mr. Uncle Doug.
wow what a great video I'm very cheap and love stuff like this, I don't have all the electrical knowledge "yet" but I can not wait to build my own amp what an inspiration you are. Thanks for taking the time to do this for all of us.
I just love listening to Uncle Doug. A lot of this information goes way over my head but it facilitates me and I love the dry humor. I figure what better way to learn what’s going on inside those amp we all love so much. I tell ya’ it’s not so bad catching a glimpse of that cool Rat Rod now and the either. I may just gain the confidence to take on my own amp project someday, so thanks for that! Keep em coming Uncle Doug.
Genius at 6:11 and I sure wish I had remembered seeing this before I made my chassis. It makes so much sense to lay it all out on a flat sheet of metal and then form the chassis to fit. I just learned the hard way that making the chassis first is far less efficient. I have plenty of room but not where I need it.
@@UncleDoug I understand. I really just have one problem; I want perfection and I want it immediately. :-) I built a nice and very sturdy chassis out of aluminum and spaced the tube sockets very nicely, but created a conflict with the ideal location of the components. I may try P2P and scrap the parallel tag strip idea. It's all fun. Thank you for the note!
Hey Uncle Doug, I just re-discovered this "blast from the past". You always strike that perfect balance between teaching, background information and humour. Wonderful video, thanks a bunch ;-)
Look what I have and just learned, Dennis - The Eico 147 will have a transformer that will power the “5F1” (class A Champ style) amplifiers. In fact the 147 also has the tubes and the plate transformer you need. I have this Eico 147 that was robbed of it control switch but looks like new. Now I learn I can use it to build an Amp like this video. Oh boy. We are in trouble now. Thanks for all your videos. Dennis
You KILL me Doug ... Im an (71) guitarist with a blues junior I love BUT it's a bit heavy for a jam sooooo I might try to build this one! LOVE your vids and your attitude!
The Chinese slip roll, finger brake, shear combo, from Harbor Fright for $300, is actually not a bad tool for light duty bending. especialy aluminum. I wish they made a cheap finger break in 8', but for amp chassiss, this seems like it would be perfect. I have a 10'brake, but it will only do 2 side of a box, as it is not a finger brake. lovely project. thank you.
You've got me rummaging though the thrift stores now in search of a PT that will work in my Tweed Princeton. Viva old iron! I added two vids today of my Champ.
Good luck with your search, dB. Keep your eye out for an old PA system amp. Sometimes schools sell off their old PA systems dirt cheap.....and they generally have some very useful parts.
Thank ,You for your answer ,I thought not not possible too, certainly not by me and my skill level but I felt I had to ask though seeing you were using the parts from a RF repeater .Ill no more of your time with my questions you 've been very kind to answer all the best Uncle D EJ
Uncle Doug, just wanted to say a huge thank you for the instructional (and very entertaining) videos - I only discovered your channel a couple of weeks ago, but already have learned a huge amount about valve amplifier circuits, and consolidated a lot of stuff I kind of knew...! Thanks again, you are a legend.
I personally use an MESR-100 ESR meter to do capacitor testing. It uses a 100kHz test signal so it can work in-circuit, and it is more accurate than I'll probably ever need.
I love this stuff... When I repair or rebuild a amp, guitar or computer, every once and a while I get a hold of these people just to find out if everything's ok or not, so far so good, but it never seem to be enough business and it seems like people are leaving their broken down equipment in the closet... People are telling me they can't afford to fix anything even though I charge 1/3 the price of the average repair shop and most of them throw whatever together to get it working.. Most or all RadioShack Stores are closed down and Sears, JC Penny and many more are shutting down, I believe we have a problem
Good project. I remember those Fender Champ amps. Great little amp for a Gibson jazz archtop...nice clean sound from the 8 inch speaker. Prehistoric parts. Common problem with the old multi electrolytic cans..and most cases hard to find these days with minature electronics.
Greetings Doug, thanks for the reply. Indeed I have some of the same development in technical way but not as much as you do. Especially amps have my interest and also the older ones (all in fact because it's maybe more important then the guitar for tone). Mostly the old ones are today's example and in fact not so much difference. I hope you get more offers to get a grip on the oldies in order to show your interesting tube-movies and interesting analyses. From the Netherlands, greetings.
The cutter or step rims you used to make the holes is officially a "Uni-Bit"...( I meet the engineer that invented these many moon's ago.) I'm glad you mentioned Harbor Fright.....They are quite a bit less expensive then the originals....I told my neighbor who borrows my set from time to time...at $20.00 you can't go wrong... They do a great job...more like milling than drilling ....great for the tool box...takes up no room...much much much better tan lugging out and paying for a knockout set...........Just FYI
I agree completely, William. Some people scorn Harbor Freight, but their prices are hard to beat. Yes, the tool will probably wear out, but you can replace it twice for less than what a high-dollar version costs. Thanks for your input :)
Greetings, Ric. Ever since I was a little kid, I loved to take things apart to see how they worked. My ability to put them back together didn't develop until much later......much to my parents' displeasure :))
Thank you for such an insightful video. I have been doing this sort of thing for years and I think it is important to show people what is possible from what most consider to be 'junk'. I am currently making a Vox ac-4 out of a late 30's Supreme oscilloscope. I love using old equipment for amp projects, they look cool and it saves them from the landfill. Great work Doug and I look forward to part 2.
Greetings, Brett. I thought my project was ambitious, but making an AC4 out of an ancient oscilloscope boggles the mind !! You should make a video of the process. Thanks so much for your kind words and interesting input.
You have a great channel. I think you help out lots of people. I am trying to turn a Leslie 44w organ amp into a guitar amp. Its field coil 70v, I want to change to 8 ohms and up date the input for a guitar preamp I have. You are helping me a lot.
Thanks, Judge. If the output transformer's secondary only has a 70V output (probably for constant-voltage PA speakers) then you will have to replace it. Installing or modifying the pre-amp is a more complex issue. Check the Internet forums for info and advice on how to do this. Good luck with your project.
Another very informative and enjoyable video Uncle Doug. When you mentioned ordering the transformer, I started poking around for a video showing how they're made. I know they're "wound" with copper wire but have never seen the process. Found this one from fellow in Japan who built his own CNC winder. I thought it was fascinating to watch him and the machine work. Feel free to delete if you don't want it cluttering up you channel or is inappropriate. Most of your subscribers seem sophisticated enough that it may not be useful or interesting to them. How to make the audio transformer
Thanks Uncle Doug. You and your viewers may also enjoy this one--Claude Paillard's video of him hand making vacuum tubes with an assortment of jigs and tools he's made and old machines. His hand work bending the plates and filaments is really fun to watch. Hand Made Vacuum Tubes by Claude Paillard
These guys really try to do it all themselves. I thought I was handy, but when you start winding your own transformers and making your own vacuum tubes, you have taken the hobby to a completely different level. Again, thanks for an interesting link.
You're welcome Uncle Doug. Glad you enjoyed them. Make magazine had a link to Paillard. I confess to watching it several times. I agree that these guys are in another realm-science meets art or something like it. Another guy like this related to your motor-head interests is Paul Brody at flashbackfab.com. Among other things, he's recreated an 1919 Excelsior 1000 cc board track racer from two original lower case covers and photos, as well as a steam powered bike. He actually built 2 Excelsiors, put one in a modern frame and races it. It's Ruby Racer 2.0 if you look at the site. He's a great guy and responds if you e mail.
I just came across this project (new subscriber), bet hey, better late than never. I have a feeling that I will learn a bunch from this, so thanks for that. Joe
Thank you for taking the time to post the explanation of how this tube amps work. I'm new with playing my guitar and slowly learning about the different types of amps and tones. I want to build the amp you described and am wondering if you have a parts list written out or can I just pull the parts of your video. Your help is most appreciated.
You're welcome, Joe. I don't have a parts list, since the amp was simply built from spare parts I had laying about, but you can use the schematic to create one. Best of luck with your project.
Greetings. Yes, I use a lubricant called Alumicut by Mystic Metal Mover, Inc. for all drilling and machining (with lathe and mill) all metals, including (in this case) steel. It's magic.
do you know the specs or the transfromer that's hardest to find? I know a store near by that has walls and walls of transformers. I would gladly help you source a transformer, if you help me learn what specs to look for and in return, i'll send you one, without the middle-man price (aside from shipping, which I also get discounts on). - just let me know if you need any transformer at a certain spec and i'll gladly check!
Any time you're trying to pick out a transformer, go to a site like Triode Electronics and look up the transformer that is recommended for the circuit you want to build. They provide all the specifications for each transformer on the site.
Great informative videos Uncle Doug. You are a one of a kind. I have a request, Any chance you can do a video on the best way to add reverb and tremolo to both channels of a Fender SF Deluxe Reverb or similar.
Thanks so much, Manny. If you wanted to have tremolo and reverb for two guitars at once, it would probably be easier to simply add a second input jack to the Vibrato channel. Rewiring the circuit to make this happen might be a little tricky.....I'll give it some thought.
Great tutorial! I owned a single knob Champ back in the 80's and have regretted selling it since then. I'll start collecting parts and put this on my "winter project pile" (right after I remodel our bathroom...) Should be a fun project. Is there any chance you've worked on a Harmon Kardon Citation amp? It's a beast. We got one, along with matching pre-amp, from my wife's family. I understand it needs all caps replaced. Thanks!
Hello Uncle Doug. I think I'm going to try my hand at building a Champ. my question is do you recommend using the exact value resistors that appear on the schematics found online? iv'e heard you talk about the stronger voltages of modern outlets. thanks in advance for answering.
Thanks so much, X. Good luck with your project. I'm not sure what you mean by "out the back". With a floor-mounted chassis, the speaker front-position is natural.
I have been getting soild state chassis and using them you just have to cut the tube socket holes every thing else is drilled makes my builds faster and factory looking as well
"What I call Christmas tree bits, I don't know if that's really what they're called but I think you can see why I call them that." -probably the funniest thing I've heard all week.
hey doug, i just made a chassi from a old 486 computer case came out well ... just a thought. one of the first amps i made was 2 6l6s great military grade cost 45 pence , metal cases that were live with b+ on them ouch!!. i put dc on the heaters and a big cap to smooth 99.999 hum free.i like mos fet out put and the chicken chomain see a 350 watt 8 devices for to for 25 pounds . and from a car boot got 5 high power hifi amps technics, 2 sony, and2 rotel for 5 quid abt 10 dollers. transformer heaven. ended ep with a 35 0 35 which gave a cool 229 watts on each modual.. then i used 3 ecc83 valves ran at 25 volt b+ wich gave input and tone. then on u tube a12ax7 runnung 12v as a overdrive. man its loud. i love mos output , but hell i cant finish a amp cover.your finess for covering blows me away. great work doug i luv the vids thank you
freak55beat You're welcome, FB. We're glad the videos are helpful. It sounds like you have really been busy :) Keep up the good work.....and keep watching.
Uncle Doug, Your videos are so GOOD! You explain things in depth. They are very inspiring and informative. I wanted to say THANK YOU! I am a musician and I love amps. I would like to learn more about how amps work and your channel is a great place to start. I know little about the circuitry and scientific principles which govern guitar amplifiers. Do you have any books you could recommend that would help me get started learning about guitar amps? Thanks again -CAL
Cal Lamkin You're welcome, Cal. I'm glad the videos are helpful. Gerald Weber has published several very good books on tube amps, most of which are available on Amazon.com. Good luck with your pursuit of knowledge.
Hey Doug, I've gotten obsessed with your videos. So much good information. Im wanting to build a very simple tube amp for a turntable. I'm looking for quality sound not blasting my windows out. Have you made a video on such a circuit or do you have a recommendation on a particular circuit.? P.s. I'm new to tubes, are ice cube relay sockets the same for tubes.? They look as if they are the same socket.
Great to hear, AD. You can't go wrong with a Fender Champ circuit such as the 5E1 or 5F1. You may have to alter the input impedance to suit the phono cartridge. Good luck. It's hard to say about the sockets. You might be better off just buying proper tube sockets......they are inexpensive.
I really appreciate your presentations, and want to launch a "Fender 5F1 Champ" build. I used to have gobs of old tube type electronic gear - got rid of all in 90's - big mistake.. I am going to go rouge and use a bridge rectifier. I found a Bridge Rectifier 600 Volt 35 Amp for under $8. Probably overkill, but to me worth it. Thoughts?
I'm not a fan of any sort of diode rectification in a small tube amp, Ronald. The beauty and purity of the Fender Champ circuit requires, in my opinion, tube rectification. If you do decide to proceed with the FWB, then the one you found would be adequate.
Hi Uncle Doug. I happen to have a blackface Vibro Champ, but I don't like it as the distortion is harsh to me. I was under the impression that in order to get smooth distortion, you needed two power tubes. If this is true, then there must be somethign wrong with my amp? (I also have a couple 10 in speakers laying around, the 8 is way to small and boxy sounding for me. I could build a cab for them I suppose).
Any BF Vibro Champ that has harsh distortion must have some circuit problems, including tube bias, ED. Single-ended amps offer some of the sweetest distortion you will ever hear, so two output tubes are definitely not required. Check the status of your 12AX7 pre-amp tube and the bias of your 6V6. Any increase in speaker size will provide much better tone. The two 10's would make a huge difference.
You're welcome, Eric. In my opinion, in the vast majority of cases, standby switches cause more harm than good. The Valve Wizard explains why: www.valvewizard.co.uk/standby.html
Nice video! Regarding the power transformer map how did you go about determining which lugs performed which function? Hey! I just noticed you've got a video that will likely answer my question! Thanks. 👍
I recently came across a Stromberg Carlson 1052 Tube Radio. I am considering taking it apart and modifying it into a Fender Champ type schematic using some of the old components and chassis. Aside from the Preamp tube being a 6AV6 the rest of the circuit looks very similar. Instead of trying to convert the chassis over to take a 12ax7 would it make sense to try to come up with a schematic that just uses two 6AV6 tubes for a preamp section?
You could, I guess, but instead of adding another tube socket, you might consider changing the 6AV6 socket to 8-pin and using a 6SL7 duo-triode instead. You'll have great tone without taxing your power transformer.
In this case, with relatively thin sheet metal, I use 2 x 4's and a vise.....maybe with a little heat to facilitate the process. If I had a square inch of free space, however, I would get a brake.
Really cool video. I have always wanted to learn about building and repairing amps and such. Any suggestions on a good starting point for a beginner? I don't know how to read the schematics or any of that stuff. I am fairly handy though so I think I could learn.
Thanks, Ben. You need to study Internet sites and watch videos to gain all the knowledge you can, as if you were back in school, taking notes and drawing diagrams. Gradually, as you gain in knowledge, the terminology and schematics will begin to make sense. It takes a fair amount of time, focus, and effort to accomplish this goal. Good luck.
I'm thinking of building my first amp but unsure of how to determine the size I need for the power and output transformer. I seem to remember you made a video a while back that explains it, but can't seem to find it.
I explain that in the Supro Trem-O-Verb video series, I believe. You can always just look up the transformers recommended for the circuit you are building on the Triode Electronics site.
I’ll be dog after watching a dozen or so videos of yours I thought to my self... Self, That old 6$ Precision 200D signal generator would probably be a good head start to scratch one out.. just yesterday I separated it from the frequency switching coil things and the air transformer.. What a stroke of timing and luck, I believe you have the exact unit from the 40’s hand written service dates go back to 49 so I’m guessing... Will you get more than a power supply and pre-amp? I’m gonna get back to the video now. Had to stop and write you a line when I saw the precision guts... 5y3 I know but I’m anxious to find out about the 6u8a and 6Au6. ....
You Sir, are a master workman Uncle Doug. Will you be auctioning off the amp to some of your more ardent fans? Hope you have a wonderful holiday season with friends and family. See you in the new year Uncle Doug.
Thanks, F86. I hadn't considered the auction idea. Maybe if I throw in a photo of Rusty it will boost the value :) Likewise to you re the holiday season.....I hope it's a great one for you and yours.
It's a Blue ESR meter from Anatek Corp in Amherst, NH. Call (603) 672-0172 and talk to Pam McKinney. They run about $100 assembled, and $75 or so in kit form.
Thanks again for the lesson, Uncle Doug. My expertise is in wood, so bear with me here! To get the numbers on the transformer, you put 120V into the input then tested the leads with a meter to get the rest? Also, I'm assuming there wasn't the selection of things you have today back then, to the "champ type" transformer was fairly common in the audio world? Thanks Again
Thanks, Tom. I disassembled the signal generator and thus was able to trace each of the power transformer wires to determine their purpose. Otherwise, yes, you can simply connect the AC primary and carefully measure the output of each colored pair of secondary wires. Such transformers were much more common back in the "good old days" :)
I use pieces of 2x4 and a vise to hold the piece and then bend the remaining metal to 90 degrees. See my video series on the Supro Tremo-Verb for details.
Jay Blue: Your inquiry was posted without any way to respond, so I'll do it here. You can post photos on my Facebook page: Uncle Doug's Vintage Amps. I may be able to offer a few ideas, but I am involved in some projects of my own at the moment and time is somewhat limited.
I do not understand why there is no respond capability to my posts. I just start typing in the Share your thoughts box, but I guess that's not what you're supposed to do. I have posted to your FB timeline about the old RCA stereo.
It turns out that you have to activate Google + to enable replies to your comments, Jay. They keep changing the way I am alerted to comments, and I fear that I may be missing some. I did see your FB posts and responded to them. I'll bet that lugging that beast up some stairs was no fun at all :)
Hello Uncle Doug and Rusty. Great Videos! I was wondering if you could explain how you mapped the power transformer that you are using in this amp build?
Greetings and thanks, Andrew. When harvesting a power transformer (PT) from an old junk chassis, it's always best to trace and mark the transformer leads prior to removing them from the chassis....which is what I did in this case. At this same time, you can determine the current capacity of each winding based on the type and number of tubes it is powering in the (junk) chassis. With a loose (out-of-chassis) PT, however, you cannot determine the current capacity of the windings.....but you can usually figure out the identity of the leads. Since I have been asked how to do this so many times, in the next day or two I will produce and upload a video demonstrating the process.
With regard to power supplies I am from New Zealand where the power supply is 240volt AC 50 hz. What changes need to be made to the transformer and valves etc to accommodate the change in voltage and frequency to achieve the same result? Does the frequency affect the possibility of hum? Can I just check the outputs from a candidate power transformer and go ahead if it matches the demo you have in the video? I have an old photo lab strobe with a lot of valves, resistors and power transformers I have saved from destruction that lead me to this amplifier idea and you have supplied the technical side. It has some very large capacitors inside, the size of baked bean cans, that look like they will hurt if handled badly.
+Grant H Amplifier transformers that are built to accept 240VAC @ 50Hz automatically put out the appropriate high voltage for an amp circuit. However, I have a feeling that a photo lab strobe might not be suitable for an audio amplifier. It was intended to charge up the huge capacitors you noted, which then would discharge several thousand volts through a very stout bulb. You would have to find a schematic for the circuit to see if it had the proper voltage outputs. If you do, let me see it and I can provide some insight.
+Grant H The strobe is a C&P Strobe Equipment Ltd, London, piece of equipment. I have been unable to find any manual online. It uses a pair of large AU5 valves which are 1/2 wave rectifiers, I have worked out, to charge the 8 capacitors as the top terminal is directly connected to the +ve of the caps. The rest of the circuit would seem to be the trigger controls. The other 2 valves are a 6SN7 and a 574 that I have not traced the circuits for yet. Interesting piece of equipment. It has a variable switch that alters the flash energy up to 1000 joules according to the 4 indicator light labels on the top. The power transformers are interesting to me as there are 2 and they look similar to the units you used in the parts amp. I will remove the input transformer and do the checks described in you video. Now I have found your videos I can not absorb enough of them. Very interesting. I have some old valve equipment on watch on our version of ebay called Trademe. I will make an amp one way or another. Thank you.
Don't give up, Grant. Building your own amp is a very challenging and rewarding experience. The 6SN7 is a familiar tube, but the rest of the components sound a bit exotic. Good luck with your parts acquisition :)
Hey Uncle Doug, thank you for you excellent videos, you inspired me to build a champ with parts that I have. This leads to my question: I have a power transformer with a secondary of 300 VDC & 150 mA. The 5f1 schematic asks for 325 VDC. Will my power transformer work for a fender champ 5f1 clone?
Yes, it will work just fine, GM. Your plate voltage may be a bit lower than the original......but this will not be an issue. It will still sound great.
Do you see many series filament amps any more? I'm curious because I'm sure there are millions is NOS tubes of various types that could be used for use in making music instead of V-hold circuits. Compactrons will never be used otherwise. Plus isolation transformer manufacturers could get a income boost.
@@UncleDoug just got the local self improvement classes for those over 50/ brochure from my local community college. A little brush up on trigonometry and pre-calculus and time to go junkin' for trannys. Wow that came out wrong. I meant scrapping in order to find trannys. Whew, what would me mum think if she knew I junked.
Hi Doug, Top Notch as always! I am curious though, what methodology did you use to bend up your chassis? I have always found this job a pain in the royal proverbial! Cheers, Dan
I was going to show the process, but it's tough to video while you're doing it. I clamp the part to be bent between flat boards in the vise, with the bending line at the upper edge of the boards. Then heat the area where the bend will be, and using another flat board, bend the top over 90 degrees, much like a sheet metal brake does. To sharpen the bend, while its all still in the vise, I strike the upper part with a hammer (flat board in between for protection). Hard to describe and probably to visualize, but it works....at least with medium-thick metal.
Uncle Doug Thanks for that Doug. Wow, heating is the secret! It looks great and came up trumps, though. Sorry to be a pain, do you apply the heat with a blow torch? Or some other device? Regards Dan
No problem, Dan. Yes, I use a propane torch to heat the metal quite hot. The wood doesn't generally "enjoy" this very much (it gets black in the area near the bend line), but it really helps to soften and sharpen the bend. You can really feel (and see) the difference between a cold and a hot bend. I suggest some practice before you start bending anything important....:)
I have a question Uncle Doug , watching this video ,is it possible to change a RF amplifier into a audio/guitar amp ? I didn't think that was do-able .I have access to 2 or 3 high watt RF amps,all older 1960's era ham and one large military amps all are tube amps
+Eddie Joe Gongre I wouldn't think that a dedicated Radio Frequency Amplifier could be converted into an Audio Frequency Amp, EJ. The significant frequency difference would probably render virtually all of the parts unsuitable....except, perhaps, for the power transformer. In the past, I have cannibalized several old RF amps and transmitters for parts, like toggles, pilot lights, tubes, sockets, etc.
Can you explain the discrepancies I see in the 5F1's schematic online? Some show a 1.5k connected to pin 5 of the 6V6. Others show a 470Ω resistor between pin 4 and the 2nd filter cap. Why is that?
The original 5F1 circuit has neither of these modifications. The 1.5K is a grid-stopper to prevent oscillation and the 470 is a screen resistor, which is not needed unless a filter choke has been substituted for the 10K nodal resistor.
To be honest, I have no idea what kVA it was, XD. I assumed it would be adequate for my uses since in its original chassis, it powered tubes of similar voltage and current requirements as the ones I intended to use. With a random transformer, removed from its chassis, I personally know of no way, other than an educated guess (based on mass and wire gauge I suppose), to deduce this. Perhaps a viewer can provide some insights. Meanwhile, for those wondering about kVA, here is an informative site: www.jeffersonelectric.com/s3/site/catalog/basics.pdf
Mine didn’t have the square Canister beside the 450 can cap.. I get 800 V are better off of my can cap and 5y3 ... only 2-5 volts everywhere else. Also mine had nice stainless steel cases pots and 100volt Restat/on off switch. Also solid copper Faraday boxes over the RF controls.. It was probably tore apart for those copper boxes, they were nice hand hammered red copper boxes.
Uncle Doug I measured with all the tubes in circuit. I had only removed the RF parts. Witch are in excellent shape if you’d want them to try and bring the Precision 200 back. However I do believe mine is one model series later than yours. The 200D. I believe the frequency coils are fixed but instead two calibration wheels err more like and exposed wiper? One one each side of the ground loop.
Is the filament winding on the pt 12 volts with a centertap or 6 volts with a center tap? I have an old pt with a 12 volt winding and center tapped to the case of the transformer. Id like to use it for this purpose.
Generally, the filament winding is 6.3VAC with a center-tap. If you only use one-half of a 12V winding, be sure that the current capability is up to the needs of the circuit.
Uncle Doug I think it should be, as it was designed to power five 12 volt heaters. There is no physical center tap though, it is tied to the case along with the hv ct.. so Im not sure about that.
hey uncle doug i wanted to build one of these for myself. if i dont have any fitting transformers laying around, could you recommend a particular power and output transformer i could order online for this unit? thanks that would help alot
+Marco C You should check out the Triode Electronics site, Marco. They offer all sorts of great transformers at reasonable prices, and they tell you which amps they are suitable for. Another good site is ClassicTone Transformers.....they build many of the transformers that are sold by Triode (prices are the same for both).
I have a kustom groove bass amp 1200 watt that turn on and i get sound out of the DI through a PA ( equalizer and all ) but nothing to speakers, Any Ideas? I found an Heathkit Ag-9a that looks like it has these same parts. It turns on but nothing but hum comes out( no ohms or sine)
I wonder if the output transistors have failed, Curtis. I'm not an expert on transistorized circuits and not good at long-distance trouble shooting.....sorry.
+ian “valve doctor” forster Ian, it's a real "stone age" technique involving 2 x 4's, a big vise, and a hammer. I think if you look in the comments section, I explain it in detail to another viewer.
hello uncle doug, can you tell me what is the output voltage for the 5f2a amp? is it 320V rms or 305V rms? I googled it but wasn't able to find good results. thank you in advance. 😊
+Harsh Karelia I don't own an original Fender 5F2A, HK, but in the clone I built of the circuit, using a 40-18019 power transformer: www.classictone.net/40-18019.pdf , the Plate Voltage for the 6V6 was about 350VDC and the Screen Voltage was about 345VDC. Your voltage readings both seem low to me, so I would think that the 320V value was closer to correct.
Hi Doug, I've been watching your series of videos on this amp as well as other. I've got to say, this extremely amazing of you. These videos are extremely informative and curve the guess work outta some of the steps. My question today is, in this particular video, you said you ordered a "transformer output", I believe, where do you order (when you order) your parts from?
It was an "output transformer", Javier, and I ordered it on the Internet from Triode Electronics: store.triodestore.com/diy-fender-g15-reverb-k15.html They carry ClassicTone transformers, which are very reasonably priced and of excellent quality.
Thank you Doug. watching your videos makes me want to learn more about how to build and fix amps. is there any advice or books or other videos that you would recommend to help with learning about amplifiers? Thank you again for your information.
The Internet is a wonderful resource, Javier. I use it to do research for all my videos. There are also some very good books on tube amp circuits by Gerald Weber. They are available on Amazon. You're welcome. Good luck :)
I enjoy watching and decided to subscibe so I wont miss anything. Are you going to add reverb to this amp? I would like to know a non-destructive way to add reverb to a 1956 fender 5f1 champ.
Greetings, Grady. Reverb requires at least a couple of extra tubes, a tank, and a transformer to drive it, and there is simply no easy way to add it on to a circuit that was not designed for it. About the only way to add reverb to a non-reverb amp is with a pedal or with a stand-alone reverb unit, like the Fender 6G15. Thanks for subscribing :)
Merry Christmas! Hope you are having a great holiday. I hate to bother you and if I am just ignore me and I will go away. Could you make a video showing how to add a line out from the 5f1 to plug into another amp to take advantage of more wattage and effects? See, I play harmonica and the 5f1 is setup perfectly for that purpose. If I could line out to my Bronco 40 that has all the effect pedals built in I think I am golden. Using a mic and harp with the Bronco 40 produces hum when chording. I figured the signal would sound the same coming out of the bronco as it does sent from the 5f1. I don't mind paying for help.
Merry Christmas to you, Grady !! Check out my video on the 1953 Tonemaster amp. The modification you seek was already done on this amp when I got it. If you read some of the comments, a man who does these modifications for harmonica players adds a lot of info. See if this isn't what you're looking for.
Greetings, Stan. First I cut out the external shape with a band saw, then clamped each of the four sides (one at a time) between two 2x4's (cut to same length as the side) in a vise and folded the top over to form a 90-degree bend. The 2x4 prevents warping of the side and provides a sharp edge for the bend. I hope this makes sense.
Glad I'm not the only one that builds things out of junk box parts! Actually working on a junkbox set at the moment! All being made from left over parts, junk parts and sets :) Forum post here : antiqueradios.com/forums/viewtopic.php?f=4&t=302145
Thanks, BT. Part 2 is in the works. I received the output transformer (a day early) and have been wiring all day. With any luck, it will be done tomorrow. Then......the smoke test :))) I'll check out your 5F1.
hello mr doug ,5f1 circuit i have noticed circuit layout has 470 OHM 5 watt wire wound resistor,and i have some spare 470 OHM 7 watt instead of 5.can you please tell me that if i still can use it or it will effect the other components?your help much appreciate.
Alvin s Greetings, Alvin. In resistors, you can increase the wattage and cause no harm at all to the circuit. In fact, higher wattage resistors tend to last longer. The 7W resistor will work just fine.
Now I know where that 'for sale' sign went that I had in front of my place! :) Sneaky devil! Sorry~I'm in the middle of an Uncle Doug binge...carry on Sir...
Yes Uncle Doug it WAS my beachside condo...but beer and pizza will put you in the poor-house if ya don't watch it~trust me on that one people! I did not have to sell it after all...the bank just kicked me out after I stopped opening my mail and answering the phone. Still not sure why they insisted that I go but it's hard to argue with the Sheriff when you're drunk on domestic beer--logic goes straight out the window! Whattayado? I figure what's one lousy fer sale sign between friends anyhow? Glad you could put it to use! 'Arrows of neon and flashing marquees down on main street, Chicago, New York, Detroit and it's all on the same street...your typical city involved in your typical daydream~Hang it up and see what tomorrow brings" Keep on Truckin' Uncle Doug~you're the best!
Well, that's what the real estate business is all about dontcha know? Location, location...by the way I've got a bridge for sale in New York if you're thinking of investing out east.
I have a very sophisticated sheet metal break consisting of two short 2 x 4's and a vise. Clamp it down with the wood edge corresponding to the desired bend......then bend, dammit, bend !!!
This is exactly the video I've been looking for and precisely the kind of amp I want to build. I really appreciate this video. Thank you Mr. Uncle Doug.
You're welcome, OT :)
wow what a great video I'm very cheap and love stuff like this, I don't have all the electrical knowledge "yet" but I can not wait to build my own amp what an inspiration you are. Thanks for taking the time to do this for all of us.
Jimmy E You're welcome, Jimmy. Be sure to learn all the safety rules before you start your own project, and then best of luck with it.
I just love listening to Uncle Doug. A lot of this information goes way over my head but it facilitates me and I love the dry humor. I figure what better way to learn what’s going on inside those amp we all love so much. I tell ya’ it’s not so bad catching a glimpse of that cool Rat Rod now and the either. I may just gain the confidence to take on my own amp project someday, so thanks for that! Keep em coming Uncle Doug.
You're welcome, RR. Thanks for all your nice comments.
Looking forward to seeing and hearing the finished product! Thanks for the videos Doug!
Thanks, Andy. Part 2 should be posted in a few days. See you then !!!
Genius at 6:11 and I sure wish I had remembered seeing this before I made my chassis. It makes so much sense to lay it all out on a flat sheet of metal and then form the chassis to fit. I just learned the hard way that making the chassis first is far less efficient. I have plenty of room but not where I need it.
Making anything like this from scratch is always a learning process, Randy. I shudder to recall some of my early efforts ;)
@@UncleDoug I understand. I really just have one problem; I want perfection and I want it immediately. :-)
I built a nice and very sturdy chassis out of aluminum and spaced the tube sockets very nicely, but created a conflict with the ideal location of the components. I may try P2P and scrap the parallel tag strip idea. It's all fun. Thank you for the note!
Hey Uncle Doug, I just re-discovered this "blast from the past". You always strike that perfect balance between teaching, background information and humour. Wonderful video, thanks a bunch ;-)
You're welcome, Stony. Thanks for your nice comments :)
Look what I have and just learned,
Dennis - The Eico 147 will have a transformer that will power the “5F1” (class A Champ style) amplifiers. In fact the 147 also has the tubes and the plate transformer you need.
I have this Eico 147 that was robbed of it control switch but looks like new. Now I learn I can use it to build an Amp like this video. Oh boy. We are in trouble now. Thanks for all your videos. Dennis
You're welcome, Dennis. Best of luck with your project.
Your videos are amazing. You explain everything so well. Thanks for taking the time to post. I actually understand amplifiers now because of you!
You're welcome, Thomas. We're glad you enjoy our videos :)
You KILL me Doug ... Im an (71) guitarist with a blues junior I love BUT it's a bit heavy for a jam sooooo I might try to build this one! LOVE your vids and your attitude!
Thanks so much, NYS. Let us know how it turns out :)
The Chinese slip roll, finger brake, shear combo, from Harbor Fright for $300, is actually not a bad tool for light duty bending. especialy aluminum. I wish they made a cheap finger break in 8', but for amp chassiss, this seems like it would be perfect. I have a 10'brake, but it will only do 2 side of a box, as it is not a finger brake. lovely project. thank you.
You're welcome, Pete, and thanks for your helpful suggestion. Rusty and I will look into the brake on our next trip to HF :)
You've got me rummaging though the thrift stores now in search of a PT that will work in my Tweed Princeton. Viva old iron!
I added two vids today of my Champ.
Good luck with your search, dB. Keep your eye out for an old PA system amp. Sometimes schools sell off their old PA systems dirt cheap.....and they generally have some very useful parts.
Thanks for the info.
Thank ,You for your answer ,I thought not not possible too, certainly not by me and my skill level but I felt I had to ask though seeing you were using the parts from a RF repeater .Ill no more of your time with my questions you 've been very kind to answer all the best Uncle D EJ
+Eddie Joe Gongre You're welcome, EJ. Best of luck with your projects :)
Uncle Doug, just wanted to say a huge thank you for the instructional (and very entertaining) videos - I only discovered your channel a couple of weeks ago, but already have learned a huge amount about valve amplifier circuits, and consolidated a lot of stuff I kind of knew...! Thanks again, you are a legend.
Thanks so much, Simon. Welcome to our channel, and best of luck with your self-education in tube electronics.
I have this same frequency generator in a closet upstairs..it's really clean for its age
Thanks for sharing, Z.
I personally use an MESR-100 ESR meter to do capacitor testing. It uses a 100kHz test signal so it can work in-circuit, and it is more accurate than I'll probably ever need.
It sounds like a fine instrument, D20.
Awesome!... my forte'.... building stuff from junk...especially electronic stuff with vacuum tubes.... I love that ! :-)
Glad you like it, Terry :)
Great video Doug! Thanks!
You're welcome, Kevin. I'm glad you liked it.
I love this stuff... When I repair or rebuild a amp, guitar or computer, every once and a while I get a hold of these people just to find out if everything's ok or not, so far so good, but it never seem to be enough business and it seems like people are leaving their broken down equipment in the closet... People are telling me they can't afford to fix anything even though I charge 1/3 the price of the average repair shop and most of them throw whatever together to get it working.. Most or all RadioShack Stores are closed down and Sears, JC Penny and many more are shutting down, I believe we have a problem
Radio Shack's departure has eliminated a good "emergency" source for components.
Very interesting ! Will be looking for part 2 !
I'm glad you liked it, Kal. I was wiring most of the day. Part 2 should be posted soon.
Outstanding work.
Thanks, Ken :)
Good project. I remember those Fender Champ amps. Great little amp for a Gibson
jazz archtop...nice clean sound from the 8 inch speaker. Prehistoric parts.
Common problem with the old multi electrolytic cans..and most cases hard to find these days with minature electronics.
SuperCarver2011 Thanks, SC.
Greetings Doug, thanks for the reply. Indeed I have some of the same development in technical way but not as much as you do. Especially amps have my interest and also the older ones (all in fact because it's maybe more important then the guitar for tone). Mostly the old ones are today's example and in fact not so much difference. I hope you get more offers to get a grip on the oldies in order to show your interesting tube-movies and interesting analyses. From the Netherlands, greetings.
Welcome aboard, Ric. It's good to hear from fellow ampoholics from around the globe. I hope all is well in the Netherlands. Stay in touch !!! :)
The cutter or step rims you used to make the holes is officially a "Uni-Bit"...( I meet the engineer that invented these many moon's ago.) I'm glad you mentioned Harbor Fright.....They are quite a bit less expensive then the originals....I told my neighbor who borrows my set from time to time...at $20.00 you can't go wrong... They do a great job...more like milling than drilling ....great for the tool box...takes up no room...much much much better tan lugging out and paying for a knockout set...........Just FYI
I agree completely, William. Some people scorn Harbor Freight, but their prices are hard to beat. Yes, the tool will probably wear out, but you can replace it twice for less than what a high-dollar version costs. Thanks for your input :)
right, iv learned a bit more, now i'm back to watch this one again... good times :)
I hope you enjoy it, Paul.
Hi Doug, interesting video(s) and how interesting it is to see how things were manufactured.
Greetings, Ric. Ever since I was a little kid, I loved to take things apart to see how they worked. My ability to put them back together didn't develop until much later......much to my parents' displeasure :))
Thank you for such an insightful video. I have been doing this sort of thing for years and I think it is important to show people what is possible from what most consider to be 'junk'. I am currently making a Vox ac-4 out of a late 30's Supreme oscilloscope. I love using old equipment for amp projects, they look cool and it saves them from the landfill. Great work Doug and I look forward to part 2.
Greetings, Brett. I thought my project was ambitious, but making an AC4 out of an ancient oscilloscope boggles the mind !! You should make a video of the process. Thanks so much for your kind words and interesting input.
Brett's a class-act, you're in good hands!
I'm stoked about this video set!
Greetings, Jorma. I'm glad you enjoyed the video :)
You have a great channel. I think you help out lots of people. I am trying to turn a Leslie 44w organ amp into a guitar amp. Its field coil 70v, I want to change to 8 ohms and up date the input for a guitar preamp I have. You are helping me a lot.
Thanks, Judge. If the output transformer's secondary only has a 70V output (probably for constant-voltage PA speakers) then you will have to replace it. Installing or modifying the pre-amp is a more complex issue. Check the Internet forums for info and advice on how to do this. Good luck with your project.
wow man this is amazing, you are really smart. im gonna learn how to build amps someday. looking forward to the next video
Thanks, Flip, and best of luck. It's not that hard once you get started...:))
Another very informative and enjoyable video Uncle Doug. When you mentioned ordering the transformer, I started poking around for a video showing how they're made. I know they're "wound" with copper wire but have never seen the process. Found this one from fellow in Japan who built his own CNC winder. I thought it was fascinating to watch him and the machine work. Feel free to delete if you don't want it cluttering up you channel or is inappropriate. Most of your subscribers seem sophisticated enough that it may not be useful or interesting to them. How to make the audio transformer
No problem, Carl. I'm sure that some viewers will find this quite interesting. Thanks for posting :)
Thanks Uncle Doug. You and your viewers may also enjoy this one--Claude Paillard's video of him hand making vacuum tubes with an assortment of jigs and tools he's made and old machines. His hand work bending the plates and filaments is really fun to watch. Hand Made Vacuum Tubes by Claude Paillard
These guys really try to do it all themselves. I thought I was handy, but when you start winding your own transformers and making your own vacuum tubes, you have taken the hobby to a completely different level. Again, thanks for an interesting link.
You're welcome Uncle Doug. Glad you enjoyed them. Make magazine had a link to Paillard. I confess to watching it several times. I agree that these guys are in another realm-science meets art or something like it. Another guy like this related to your motor-head interests is Paul Brody at flashbackfab.com. Among other things, he's recreated an 1919 Excelsior 1000 cc board track racer from two original lower case covers and photos, as well as a steam powered bike. He actually built 2 Excelsiors, put one in a modern frame and races it. It's Ruby Racer 2.0 if you look at the site. He's a great guy and responds if you e mail.
I just came across this project (new subscriber), bet hey, better late than never.
I have a feeling that I will learn a bunch from this, so thanks for that.
Joe
I hope you do, Joe. Thanks for watching :)
Thank you for taking the time to post the explanation of how this tube amps work. I'm new with playing my guitar and slowly learning about the different types of amps and tones. I want to build the amp you described and am wondering if you have a parts list written out or can I just pull the parts of your video. Your help is most appreciated.
You're welcome, Joe. I don't have a parts list, since the amp was simply built from spare parts I had laying about, but you can use the schematic to create one. Best of luck with your project.
Good JOB Uncle!
Thanks, Quick :)
FYI Its called a step bit. Use with some oil "WD40" this will extend the bits life.
thx
Greetings. Yes, I use a lubricant called Alumicut by Mystic Metal Mover, Inc. for all drilling and machining (with lathe and mill) all metals, including (in this case) steel. It's magic.
Or "step drill"
WD40 aka Wienerschleiden.(sic)
Thanx AvE
really cool you should start making them.... keep up the videos
I will, Sandy. Thanks for watching !!
If you're interested, Mr. Carlson's Lab has a video up of restoring a Precision signal generator. I found it quite interesting.
He would have had quite a time restoring this one, Daniel, especially after I stole all the key parts :)
Excellent. I believe those drill bits are for counter-sink
Thanks, Tony. The step drills are sold "for cutting holes in metal and plastic", but would probably work for countersinking also.
wow. very cool. stumbled onto one of your videos again. im going to build one without a kit.
+George Ellias Thanks, George. Good luck with your scratch-building project.
Thanks, most of the items are easy to scrounge around, however, those transformers! they can't be found anywhere but online. :/
do you know the specs or the transfromer that's hardest to find? I know a store near by that has walls and walls of transformers. I would gladly help you source a transformer, if you help me learn what specs to look for and in return, i'll send you one, without the middle-man price (aside from shipping, which I also get discounts on). - just let me know if you need any transformer at a certain spec and i'll gladly check!
Thanks for the offer, George. I will keep it in mind if I have a project in the future that requires a power or output transformer.
Any time you're trying to pick out a transformer, go to a site like Triode Electronics and look up the transformer that is recommended for the circuit you want to build. They provide all the specifications for each transformer on the site.
Nice video(s). I rebuilt an E-200-C earlier this year but mine was already in really nice shape
+Michael Lloyd Thanks, Michael.
Great informative videos Uncle Doug. You are a one of a kind. I have a request, Any chance you can do a video on the best way to add reverb and tremolo to both channels of a Fender SF Deluxe Reverb or similar.
Thanks so much, Manny. If you wanted to have tremolo and reverb for two guitars at once, it would probably be easier to simply add a second input jack to the Vibrato channel. Rewiring the circuit to make this happen might be a little tricky.....I'll give it some thought.
Great tutorial! I owned a single knob Champ back in the 80's and have regretted selling it since then. I'll start collecting parts and put this on my "winter project pile" (right after I remodel our bathroom...) Should be a fun project. Is there any chance you've worked on a Harmon Kardon Citation amp? It's a beast. We got one, along with matching pre-amp, from my wife's family. I understand it needs all caps replaced. Thanks!
Thanks, FBG. No, I have never worked on any HK stuff.
Hello Uncle Doug. I think I'm going to try my hand at building a Champ. my question is do you recommend using the exact value resistors that appear on the schematics found online? iv'e heard you talk about the stronger voltages of modern outlets. thanks in advance for answering.
The only resistor that may need to be changed is the bias resistor for the 6V6, Ernest. Best of luck with your project.
Looking to build this exact layout, but can I ask why you chose speaker on top rather than out the back? Great work!
Thanks so much, X. Good luck with your project. I'm not sure what you mean by "out the back". With a floor-mounted chassis, the speaker front-position is natural.
I have been getting soild state chassis and using them you just have to cut the tube socket holes every thing else is drilled makes my builds faster and factory looking as well
Thanks for sharing, Jim.
This is awesome
Thanks, Eddie.
"What I call Christmas tree bits, I don't know if that's really what they're called but I think you can see why I call them that." -probably the funniest thing I've heard all week.
Especially since the video was posted in December, Zach. Thanks :)
They are step bits I hope it helps
***** Oh I know! That's what made it so funny.
Could you share how you made the sheet metal bends without a brake? Maybe you have some advice on dealing with that! Thank you.
I have demonstrated the technique in my Supro TremoVerb video series, CM.
hey doug, i just made a chassi from a old 486 computer case came out well ... just a thought. one of the first amps i made was 2 6l6s great military grade cost 45 pence , metal cases that were live with b+ on them ouch!!. i put dc on the heaters and a big cap to smooth 99.999 hum free.i like mos fet out put and the chicken chomain see a 350 watt 8 devices for to for 25 pounds . and from a car boot got 5 high power hifi amps technics, 2 sony, and2 rotel for 5 quid abt 10 dollers. transformer heaven. ended ep with a 35 0 35 which gave a cool 229 watts on each modual.. then i used 3 ecc83 valves ran at 25 volt b+ wich gave input and tone. then on u tube a12ax7 runnung 12v as a overdrive. man its loud. i love mos output , but hell i cant finish a amp cover.your finess for covering blows me away. great work doug i luv the vids thank you
freak55beat You're welcome, FB. We're glad the videos are helpful. It sounds like you have really been busy :) Keep up the good work.....and keep watching.
Uncle Doug, Your videos are so GOOD! You explain things in depth. They are very inspiring and informative. I wanted to say THANK YOU! I am a musician and I love amps. I would like to learn more about how amps work and your channel is a great place to start. I know little about the circuitry and scientific principles which govern guitar amplifiers. Do you have any books you could recommend that would help me get started learning about guitar amps? Thanks again -CAL
Cal Lamkin You're welcome, Cal. I'm glad the videos are helpful. Gerald Weber has published several very good books on tube amps, most of which are available on Amazon.com. Good luck with your pursuit of knowledge.
Hey Doug, I've gotten obsessed with your videos. So much good information. Im wanting to build a very simple tube amp for a turntable. I'm looking for quality sound not blasting my windows out. Have you made a video on such a circuit or do you have a recommendation on a particular circuit.? P.s. I'm new to tubes, are ice cube relay sockets the same for tubes.? They look as if they are the same socket.
Great to hear, AD. You can't go wrong with a Fender Champ circuit such as the 5E1 or 5F1. You may have to alter the input impedance to suit the phono cartridge. Good luck. It's hard to say about the sockets. You might be better off just buying proper tube sockets......they are inexpensive.
I really appreciate your presentations, and want to launch a "Fender 5F1 Champ" build. I used to have gobs of old tube type electronic gear - got rid of all in 90's - big mistake.. I am going to go rouge and use a bridge rectifier. I found a Bridge Rectifier 600 Volt 35 Amp for under $8. Probably overkill, but to me worth it. Thoughts?
I'm not a fan of any sort of diode rectification in a small tube amp, Ronald. The beauty and purity of the Fender Champ circuit requires, in my opinion, tube rectification. If you do decide to proceed with the FWB, then the one you found would be adequate.
I hear you, it is tube rectification then.
Hi Uncle Doug. I happen to have a blackface Vibro Champ, but I don't like it as the distortion is harsh to me. I was under the impression that in order to get smooth distortion, you needed two power tubes. If this is true, then there must be somethign wrong with my amp? (I also have a couple 10 in speakers laying around, the 8 is way to small and boxy sounding for me. I could build a cab for them I suppose).
Any BF Vibro Champ that has harsh distortion must have some circuit problems, including tube bias, ED. Single-ended amps offer some of the sweetest distortion you will ever hear, so two output tubes are definitely not required. Check the status of your 12AX7 pre-amp tube and the bias of your 6V6. Any increase in speaker size will provide much better tone. The two 10's would make a huge difference.
Hi, Thank you for the Video. I apologize if this is a stupid question, but why don't you need a standby switch?
You're welcome, Eric. In my opinion, in the vast majority of cases, standby switches cause more harm than good. The Valve Wizard explains why: www.valvewizard.co.uk/standby.html
Nice video! Regarding the power transformer map how did you go about determining which lugs performed which function?
Hey! I just noticed you've got a video that will likely answer my question! Thanks. 👍
Yes, I made a video describing how to identify the leads from a PT.
Gosh I wish I could come hang with you in your work shop and learn a thing, or two, or a million.
It would be nice if we could get together with all our great viewers to drink a few beers and test a few amps ;)
@@UncleDoug I'd be there in a heartbeat! Thanks for the great content!
@@josephgray4659 You're welcome, Joseph :)
I recently came across a Stromberg Carlson 1052 Tube Radio. I am considering taking it apart and modifying it into a Fender Champ type schematic using some of the old components and chassis. Aside from the Preamp tube being a 6AV6 the rest of the circuit looks very similar. Instead of trying to convert the chassis over to take a 12ax7 would it make sense to try to come up with a schematic that just uses two 6AV6 tubes for a preamp section?
You could, I guess, but instead of adding another tube socket, you might consider changing the 6AV6 socket to 8-pin and using a 6SL7 duo-triode instead. You'll have great tone without taxing your power transformer.
Great work! Can you tell me how you bent the chassis without a brake?
In this case, with relatively thin sheet metal, I use 2 x 4's and a vise.....maybe with a little heat to facilitate the process. If I had a square inch of free space, however, I would get a brake.
@@UncleDoug Thanks for the reply!
Really cool video. I have always wanted to learn about building and repairing amps and such. Any suggestions on a good starting point for a beginner? I don't know how to read the schematics or any of that stuff. I am fairly handy though so I think I could learn.
Thanks, Ben. You need to study Internet sites and watch videos to gain all the knowledge you can, as if you were back in school, taking notes and drawing diagrams. Gradually, as you gain in knowledge, the terminology and schematics will begin to make sense. It takes a fair amount of time, focus, and effort to accomplish this goal. Good luck.
I'm thinking of building my first amp but unsure of how to determine the size I need for the power and output transformer. I seem to remember you made a video a while back that explains it, but can't seem to find it.
I explain that in the Supro Trem-O-Verb video series, I believe. You can always just look up the transformers recommended for the circuit you are building on the Triode Electronics site.
I’ll be dog after watching a dozen or so videos of yours I thought to my self... Self, That old 6$ Precision 200D signal generator would probably be a good head start to scratch one out.. just yesterday I separated it from the frequency switching coil things and the air transformer..
What a stroke of timing and luck, I believe you have the exact unit from the 40’s hand written service dates go back to 49 so I’m guessing...
Will you get more than a power supply and pre-amp? I’m gonna get back to the video now. Had to stop and write you a line when I saw the precision guts... 5y3 I know but I’m anxious to find out about the 6u8a and 6Au6. ....
I got most of what I needed, 76, and had the rest on hand, fortunately.
You Sir, are a master workman Uncle Doug. Will you be auctioning off the amp to some of your more ardent fans? Hope you have a wonderful holiday season with friends and family. See you in the new year Uncle Doug.
Thanks, F86. I hadn't considered the auction idea. Maybe if I throw in a photo of Rusty it will boost the value :) Likewise to you re the holiday season.....I hope it's a great one for you and yours.
The addition of a Rusty photo will put it out of reach for us mere mortals...lol.
Interest rates are at an all-time low, so it would be possible to borrow the (tens of) thousands necessary to make such a magnificent purchase.....:))
....and Rusty kindly suggested that we use the proceeds to eliminate hunger.....namely his.....for steak :)))
How does Sir Rusty take his steak? King prefers his "off my plate", bad dog! ;-)
Remind us what kind of cap tester that is please. I'm gonna pick one up for Christmas. Thanks for the videos!
It's a Blue ESR meter from Anatek Corp in Amherst, NH. Call (603) 672-0172 and talk to Pam McKinney. They run about $100 assembled, and $75 or so in kit form.
Thanks sir! Keep up the great work, we love your videos here!
I shall, Mr. Scubasky, and I appreciate your support. Have a great holiday season !!
Are those pop rivets Doug, i like the angle iron idea and to beef up the corners. D
Yes, and nuts and bolts in places, Dennis. Thanks !!
Thanks again for the lesson, Uncle Doug. My expertise is in wood, so bear with me here! To get the numbers on the transformer, you put 120V into the input then tested the leads with a meter to get the rest? Also, I'm assuming there wasn't the selection of things you have today back then, to the "champ type" transformer was fairly common in the audio world?
Thanks Again
BTW, You're correct, I have called it a Christmas tree bit for years ;)
Thanks, Tom. I disassembled the signal generator and thus was able to trace each of the power transformer wires to determine their purpose. Otherwise, yes, you can simply connect the AC primary and carefully measure the output of each colored pair of secondary wires. Such transformers were much more common back in the "good old days" :)
building a fender 5f1 champ from scratch using scrap parts
If you are doing this, then best of luck, Az. Let us know how it turns out.
Great, Uncle Doug has inspired me as well. Funny and a good teacher, I see correlation perhaps causation.
Hello Uncle Doug, I would like to build a Fender like Amplifier, are there any kits that you would recommend? Thank you very much.
CC, I understand that Weber kits are really good. Here is a link to their site: taweber.powweb.com/store/kits.htm Good luck !!!
Hey Doug, thanks for the video. How did you manage to bend this piece?
I use pieces of 2x4 and a vise to hold the piece and then bend the remaining metal to 90 degrees. See my video series on the Supro Tremo-Verb for details.
Jay Blue: Your inquiry was posted without any way to respond, so I'll do it here. You can post photos on my Facebook page: Uncle Doug's Vintage Amps. I may be able to offer a few ideas, but I am involved in some projects of my own at the moment and time is somewhat limited.
I do not understand why there is no respond capability to my posts. I just start typing in the Share your thoughts box, but I guess that's not what you're supposed to do. I have posted to your FB timeline about the old RCA stereo.
It turns out that you have to activate Google + to enable replies to your comments, Jay. They keep changing the way I am alerted to comments, and I fear that I may be missing some. I did see your FB posts and responded to them. I'll bet that lugging that beast up some stairs was no fun at all :)
Hello Uncle Doug and Rusty. Great Videos! I was wondering if you could explain how you mapped the power transformer that you are using in this amp build?
Greetings and thanks, Andrew. When harvesting a power transformer (PT) from an old junk chassis, it's always best to trace and mark the transformer leads prior to removing them from the chassis....which is what I did in this case. At this same time, you can determine the current capacity of each winding based on the type and number of tubes it is powering in the (junk) chassis.
With a loose (out-of-chassis) PT, however, you cannot determine the current capacity of the windings.....but you can usually figure out the identity of the leads. Since I have been asked how to do this so many times, in the next day or two I will produce and upload a video demonstrating the process.
Uncle Doug wow! thanks.
You're welcome, Andrew. I just finished posting the video. I hope it clarifies the procedure adequately.
A pleasure to watch!
Thanks, SS. I'm glad you enjoyed it. Part 2 is in the works !!
With regard to power supplies I am from New Zealand where the power supply is 240volt AC 50 hz. What changes need to be made to the transformer and valves etc to accommodate the change in voltage and frequency to achieve the same result? Does the frequency affect the possibility of hum? Can I just check the outputs from a candidate power transformer and go ahead if it matches the demo you have in the video? I have an old photo lab strobe with a lot of valves, resistors and power transformers I have saved from destruction that lead me to this amplifier idea and you have supplied the technical side. It has some very large capacitors inside, the size of baked bean cans, that look like they will hurt if handled badly.
+Grant H Amplifier transformers that are built to accept 240VAC @ 50Hz automatically put out the appropriate high voltage for an amp circuit. However, I have a feeling that a photo lab strobe might not be suitable for an audio amplifier. It was intended to charge up the huge capacitors you noted, which then would discharge several thousand volts through a very stout bulb. You would have to find a schematic for the circuit to see if it had the proper voltage outputs. If you do, let me see it and I can provide some insight.
+Grant H The strobe is a C&P Strobe Equipment Ltd, London, piece of equipment. I have been unable to find any manual online. It uses a pair of large AU5 valves which are 1/2 wave rectifiers, I have worked out, to charge the 8 capacitors as the top terminal is directly connected to the +ve of the caps. The rest of the circuit would seem to be the trigger controls. The other 2 valves are a 6SN7 and a 574 that I have not traced the circuits for yet. Interesting piece of equipment. It has a variable switch that alters the flash energy up to 1000 joules according to the 4 indicator light labels on the top. The power transformers are interesting to me as there are 2 and they look similar to the units you used in the parts amp. I will remove the input transformer and do the checks described in you video. Now I have found your videos I can not absorb enough of them. Very interesting. I have some old valve equipment on watch on our version of ebay called Trademe. I will make an amp one way or another. Thank you.
Don't give up, Grant. Building your own amp is a very challenging and rewarding experience. The 6SN7 is a familiar tube, but the rest of the components sound a bit exotic. Good luck with your parts acquisition :)
uncy doug! we call those uni-bits in the hvac field.
Greetings, Padraic. It's good to hear from you. I'm sure they have many names, but in December, I like to call them "Christmas Tree" bits ;))))
Hey Uncle Doug, thank you for you excellent videos, you inspired me to build a champ with parts that I have. This leads to my question: I have a power transformer with a secondary of 300 VDC & 150 mA. The 5f1 schematic asks for 325 VDC. Will my power transformer work for a fender champ 5f1 clone?
Yes, it will work just fine, GM. Your plate voltage may be a bit lower than the original......but this will not be an issue. It will still sound great.
Do you see many series filament amps any more? I'm curious because I'm sure there are millions is NOS tubes of various types that could be used for use in making music instead of V-hold circuits. Compactrons will never be used otherwise.
Plus isolation transformer manufacturers could get a income boost.
Perhaps you should start a new craze, RB. Get in on the ground floor.
@@UncleDoug just got the local self improvement classes for those over 50/ brochure from my local community college. A little brush up on trigonometry and pre-calculus and time to go junkin' for trannys. Wow that came out wrong. I meant scrapping in order to find trannys.
Whew, what would me mum think if she knew I junked.
Yes, it's best to clarify that the trannys you seek are the electronic kind :)
@@UncleDoug I'm actually more concerned about my mom finding my junk. Dang, this English thing is hard.
I'm go sleep.
With all those trimable coils you could build a theremin.....Maybe. I think Rusty has the patience to become a pretty good theremin player.
I have often felt the urge to build a theremin, Sharkey, but have yet to do so. I'll put it on my "bucket list" :)
Hi Doug, Top Notch as always!
I am curious though, what methodology did you use to bend up your chassis?
I have always found this job a pain in the royal proverbial!
Cheers,
Dan
I was going to show the process, but it's tough to video while you're doing it. I clamp the part to be bent between flat boards in the vise, with the bending line at the upper edge of the boards. Then heat the area where the bend will be, and using another flat board, bend the top over 90 degrees, much like a sheet metal brake does. To sharpen the bend, while its all still in the vise, I strike the upper part with a hammer (flat board in between for protection). Hard to describe and probably to visualize, but it works....at least with medium-thick metal.
Uncle Doug Thanks for that Doug. Wow, heating is the secret! It looks great and came up trumps, though. Sorry to be a pain, do you apply the heat with a blow torch? Or some other device? Regards Dan
No problem, Dan. Yes, I use a propane torch to heat the metal quite hot. The wood doesn't generally "enjoy" this very much (it gets black in the area near the bend line), but it really helps to soften and sharpen the bend. You can really feel (and see) the difference between a cold and a hot bend. I suggest some practice before you start bending anything important....:)
Uncle Doug Thanks again, for your wisdom!
I have a question Uncle Doug , watching this video ,is it possible to change a RF amplifier into a audio/guitar amp ? I didn't think that was do-able .I have access to 2 or 3 high watt RF amps,all older 1960's era ham and one large military amps all are tube amps
+Eddie Joe Gongre I wouldn't think that a dedicated Radio Frequency Amplifier could be converted into an Audio Frequency Amp, EJ. The significant frequency difference would probably render virtually all of the parts unsuitable....except, perhaps, for the power transformer. In the past, I have cannibalized several old RF amps and transmitters for parts, like toggles, pilot lights, tubes, sockets, etc.
Can you explain the discrepancies I see in the 5F1's schematic online? Some show a 1.5k connected to pin 5 of the 6V6. Others show a 470Ω resistor between pin 4 and the 2nd filter cap. Why is that?
The original 5F1 circuit has neither of these modifications. The 1.5K is a grid-stopper to prevent oscillation and the 470 is a screen resistor, which is not needed unless a filter choke has been substituted for the 10K nodal resistor.
A transformer from a AA5 radio with a 50C5 output may work in a pinch if you used an 8-ohm speaker.
Thanks for the info, D20.
What kVA is the transformer? Actually since we're on this matter how do you determine the kVA of transformers in general?
To be honest, I have no idea what kVA it was, XD. I assumed it would be adequate for my uses since in its original chassis, it powered tubes of similar voltage and current requirements as the ones I intended to use. With a random transformer, removed from its chassis, I personally know of no way, other than an educated guess (based on mass and wire gauge I suppose), to deduce this. Perhaps a viewer can provide some insights. Meanwhile, for those wondering about kVA, here is an informative site: www.jeffersonelectric.com/s3/site/catalog/basics.pdf
Mine didn’t have the square Canister beside the 450 can cap..
I get 800 V are better off of my can cap and 5y3 ... only 2-5 volts everywhere else.
Also mine had nice stainless steel cases pots and 100volt Restat/on off switch. Also solid copper Faraday boxes over the RF controls.. It was probably tore apart for those copper boxes, they were nice hand hammered red copper boxes.
Did you measure that high voltage while the amp was fully functional or without any tubes other than the 5Y3?
Uncle Doug
I measured with all the tubes in circuit. I had only removed the RF parts. Witch are in excellent shape if you’d want them to try and bring the Precision 200 back.
However I do believe mine is one model series later than yours. The 200D. I believe the frequency coils are fixed but instead two calibration wheels err more like and exposed wiper? One one each side of the ground loop.
Is the filament winding on the pt 12 volts with a centertap or 6 volts with a center tap?
I have an old pt with a 12 volt winding and center tapped to the case of the transformer. Id like to use it for this purpose.
Generally, the filament winding is 6.3VAC with a center-tap. If you only use one-half of a 12V winding, be sure that the current capability is up to the needs of the circuit.
Uncle Doug
I think it should be, as it was designed to power five 12 volt heaters. There is no physical center tap though, it is tied to the case along with the hv ct.. so Im not sure about that.
Try connecting one of the 12VAC leads to one side of a tube filament and then grounding the other side. You should get 6V. Check it and see.
hey uncle doug i wanted to build one of these for myself. if i dont have any fitting transformers laying around, could you recommend a particular power and output transformer i could order online for this unit? thanks that would help alot
+Marco C You should check out the Triode Electronics site, Marco. They offer all sorts of great transformers at reasonable prices, and they tell you which amps they are suitable for. Another good site is ClassicTone Transformers.....they build many of the transformers that are sold by Triode (prices are the same for both).
I have a kustom groove bass amp 1200 watt that turn on and i get sound out of the DI through a PA ( equalizer and all ) but nothing to speakers, Any Ideas? I found an Heathkit Ag-9a that looks like it has these same parts. It turns on but nothing but hum comes out( no ohms or sine)
I wonder if the output transistors have failed, Curtis. I'm not an expert on transistorized circuits and not good at long-distance trouble shooting.....sorry.
how did you bend the edges what did you use i want to try to make a chassis
+ian “valve doctor” forster Ian, it's a real "stone age" technique involving 2 x 4's, a big vise, and a hammer. I think if you look in the comments section, I explain it in detail to another viewer.
hello uncle doug,
can you tell me what is the output voltage for the 5f2a amp? is it 320V rms or 305V rms? I googled it but wasn't able to find good results. thank you in advance. 😊
from output voltage I mean the power supply transformer voltage for b+
+Harsh Karelia I don't own an original Fender 5F2A, HK, but in the clone I built of the circuit, using a 40-18019 power transformer: www.classictone.net/40-18019.pdf , the Plate Voltage for the 6V6 was about 350VDC and the Screen Voltage was about 345VDC. Your voltage readings both seem low to me, so I would think that the 320V value was closer to correct.
Now I know this video is from some years ago but I wonder if Mr Carlson from Mr Carlson's Lab has one of them Precision Signal Generators.
He did......until I stole it and made an amp from it. Just kidding. Why not ask him?
@@UncleDoug I have had a look on the channel Mr Carlson's Lab and be did do a video on the 'Precision Signal Generator E-200-C' about 3 years ago.
Hi Doug, I've been watching your series of videos on this amp as well as other. I've got to say, this extremely amazing of you. These videos are extremely informative and curve the guess work outta some of the steps.
My question today is, in this particular video, you said you ordered a "transformer output", I believe, where do you order (when you order) your parts from?
It was an "output transformer", Javier, and I ordered it on the Internet from Triode Electronics: store.triodestore.com/diy-fender-g15-reverb-k15.html They carry ClassicTone transformers, which are very reasonably priced and of excellent quality.
Thank you Doug. watching your videos makes me want to learn more about how to build and fix amps. is there any advice or books or other videos that you would recommend to help with learning about amplifiers? Thank you again for your information.
The Internet is a wonderful resource, Javier. I use it to do research for all my videos. There are also some very good books on tube amp circuits by Gerald Weber. They are available on Amazon. You're welcome. Good luck :)
Thanks again Doug
You're welcome, Javier :)
I enjoy watching and decided to subscibe so I wont miss anything. Are you going to add reverb to this amp? I would like to know a non-destructive way to add reverb to a 1956 fender 5f1 champ.
Greetings, Grady. Reverb requires at least a couple of extra tubes, a tank, and a transformer to drive it, and there is simply no easy way to add it on to a circuit that was not designed for it. About the only way to add reverb to a non-reverb amp is with a pedal or with a stand-alone reverb unit, like the Fender 6G15. Thanks for subscribing :)
Merry Christmas! Hope you are having a great holiday. I hate to bother you and if I am just ignore me and I will go away. Could you make a video showing how to add a line out from the 5f1 to plug into another amp to take advantage of more wattage and effects? See, I play harmonica and the 5f1 is setup perfectly for that purpose. If I could line out to my Bronco 40 that has all the effect pedals built in I think I am golden. Using a mic and harp with the Bronco 40 produces hum when chording. I figured the signal would sound the same coming out of the bronco as it does sent from the 5f1. I don't mind paying for help.
Merry Christmas to you, Grady !! Check out my video on the 1953 Tonemaster amp. The modification you seek was already done on this amp when I got it. If you read some of the comments, a man who does these modifications for harmonica players adds a lot of info. See if this isn't what you're looking for.
I figured you had already done it. Thanks so much. Enjoy your holidays.
How did you bend the chassis ?
Greetings, Stan. First I cut out the external shape with a band saw, then clamped each of the four sides (one at a time) between two 2x4's (cut to same length as the side) in a vise and folded the top over to form a 90-degree bend. The 2x4 prevents warping of the side and provides a sharp edge for the bend. I hope this makes sense.
Doug where can I find schematics of the different early models to see which one I would like to try for my first build?
+Gene Sattel Just do Google searches for early Fender Champ schematics, like for the 5C1, 5D1, 5E1, 5F1, etc.
Glad I'm not the only one that builds things out of junk box parts! Actually working on a junkbox set at the moment! All being made from left over parts, junk parts and sets :) Forum post here :
antiqueradios.com/forums/viewtopic.php?f=4&t=302145
It looks like an interesting project, Hydro. Good luck with it.
Beautiful metalwork. Looking forward to part 2. My 5F1 is up and running now, video on my channel "off topic--guitar amp".
Thanks, BT. Part 2 is in the works. I received the output transformer (a day early) and have been wiring all day. With any luck, it will be done tomorrow. Then......the smoke test :))) I'll check out your 5F1.
great video uncle doug
Thanks, Franky. It's always exciting to make "something from nothing".....especially if it works as well as I hope this little amp does.
i wish you showed your process in making the chases.
Watch my video series on scratch building a Supro Tremo-Verb. The process is completely explained and demonstrated.
I call it the pyramid, but i also call it the Christmas tree :D
i wish you where my neighbour :P
Likewise, TJ :)
hello mr doug ,5f1 circuit i have noticed circuit layout has 470 OHM 5 watt wire wound resistor,and i have some spare 470 OHM 7 watt instead of 5.can you please tell me that if i still can use it or it will effect the other components?your help much appreciate.
Alvin s Greetings, Alvin. In resistors, you can increase the wattage and cause no harm at all to the circuit. In fact, higher wattage resistors tend to last longer. The 7W resistor will work just fine.
Thank you so much for taking time to answer me and sharing your knowledge..love all your videos and big hug to rusty..
You're welcome, Alvin. Rusty says thanks for the big hug, and best of luck with your repair project :)
Now I know where that 'for sale' sign went that I had in front of my place! :) Sneaky devil!
Sorry~I'm in the middle of an Uncle Doug binge...carry on Sir...
So that was your beachside condo. I should have known......from all the empty beer cans and pizza boxes :)
Yes Uncle Doug it WAS my beachside condo...but beer and pizza will put you in the poor-house if ya don't watch it~trust me on that one people! I did not have to sell it after all...the bank just kicked me out after I stopped opening my mail and answering the phone. Still not sure why they insisted that I go but it's hard to argue with the Sheriff when you're drunk on domestic beer--logic goes straight out the window! Whattayado? I figure what's one lousy fer sale sign between friends anyhow? Glad you could put it to use! 'Arrows of neon and flashing marquees down on main street, Chicago, New York, Detroit and it's all on the same street...your typical city involved in your typical daydream~Hang it up and see what tomorrow brings"
Keep on Truckin' Uncle Doug~you're the best!
What a shame about the foreclosure......beachfront condos are scarce in Arizona :) Thanks !!
Well, that's what the real estate business is all about dontcha know? Location, location...by the way I've got a bridge for sale in New York if you're thinking of investing out east.
What did you use to fold the chassis? Thanks.
I have a very sophisticated sheet metal break consisting of two short 2 x 4's and a vise. Clamp it down with the wood edge corresponding to the desired bend......then bend, dammit, bend !!!
Nice! Thanks.
What material did you use in your chasis? Is that steel or aluminum? Thank you uncle. :)
As I recall.....it was a long time ago.....the chassis was aluminum sheet, MT. Either metal will work fine for this purpose, however.
@@UncleDoug thanks uncle. You're such a great man
@@The-Master-of-None You are too kind, MT.....but Thanks :)