The thing I love about your videos is your honesty. You own it if you make mistakes, and that is refreshing. Many of us could have made the same mistake and it makes it more believable to see the videos with the mistakes included.
Love your videos. You and BIGCLIVE encouraged me to return to electronic tinkering. And love the kitty - mine sleeps on my workdesk, leaving fur balls.🐈🐱
I have my great uncle's 1954 Zenith am fm phonograph console in a beautiful cherry wood cabinet. The phonograph has the Cobramatic turntable. It all works great! I inherited it when he passed in 1994 at age 100! Since ive had it 30 years next April, its had no issues, it always plays fantastic, 0 hum, the original speaker sounds very good, all the tubes except for one, are Zenith. It will be 70 years old next month. Records play fine too. People have told me i should have it rebuilt, its a ticking time bomb for a catastrophic failure....i keep close tabs on it when using it, and i do use it several times a month, few hours each time. But it just seems perfectly fine! Even the dial light works, along with the little amber light at the bottom of the cabinet to let you know its on, if the cabinet is all closed up.
Interesting work. I have a few battery tube portables, RCA Zenith and Stromberg-Carlson, all with tuned RF stages, and enjoy listening to them. We all "screw up" from time to time. I pulled an electrolytic can on the horizontal sweep chassis of a 1948 RCA projection TV, restuffed it, and remounted it wrong on the phenolic mounting wafer. Glad I caught it before smoke was released LOL . I've been at it for 62 years, reparing my first radio at 10, a simple line cord replacement, but it created a life long interest in vintage electronic restoration and repair. Thank You very much for the video of the Zenith restoration ! 😊
Thank you Shango, for showing us that even the guys who really know what they are doing experience frustrations and dead ends. Very encouraging for those of us who are still climbing the knowledge ladder!
I restored one of these two years ago. It’s a pretty ordinary AA5 radio, but it has an RF stage, which is great. The appeal of this radio is the very thing for which it might be criticized. The “flip-up” dial is very cool, as is the instant-on switch, BUT all of that complexity comes at a price. The antenna wire is vulnerable to breaking (from metal fatigue due to opening and closing), the on-off switch mechanism is prone to failure (plastic fatigue), and the clear dial cover glass (plastic) is almost always cracked (due to hitting the knobs when closing it). All that said, mine is a beautiful example and, once restored, is an excellent performer and addition to my collection.
Thanks again Shango, I really like the longer videos. I've honestly learnt more from you and your videos than anyone else. I love the diagnosis and honesty when you make a mistake. It really makes me feel better knowing it's not just me! I'm on to my 4th tube set restoration and dozens of transistor sets behind me. Don't think I'd have got there without this videos. Thanks for all the effort, it is appreciated 👍
Those 1.4V directly heated filament tubes were originally designed for battery use. Back in the day, firms like Ever-Ready (UK market at least) made a combined battery which had both 90V HT and 1.5V LT sections. The filament cathodes are very sensitive to ripple in their supply. I've found just the same when making battery eliminators for these sets. I won't be surprised if that radio hummed like a Banshee from new when run from the mains.
nope. they are very hum free. i have about 7 that are all very quiet, main or battery. I run the A battery with 7 cells, instead of the recommended 8. But, I have one lunchbox model (forget the model) that has the same identical hum problem. It plays fine, but just fuzzy hum. I finally gave up on it.
Love how you have tubes in a bag that are all same voltage for the heaters. I have mine in a plastic shoe box but they take up too much space. So I just got some ultra thick plastic zip bags and you get the rest..... thanks shango066 love all your videos. Even the eol or look how many transistors my radio has
My brother had a radio from this era..little did he or I know that even if it runs on batteries the voltages inside can kill you,if the right conditions exist Plus these radios weighed a ton and the batteries only lasted a few hours (carbon zinc poo poo) But You were 'The Guy" to be invited to parties and camping because you could play some Rock 'n Roll! Defy your parents,the Church and all your teachers and neighbors,you were a REBEL
@akshonclip8149 the original series had 2 theme songs. 1st season for the first 7 to 10 episodes had a different theme then afterwards the one everyone knows.
I have an H500 T-O I restored probably 10 years ago, but a couple years back it started acting up with SMD and AVC issues from a few resistors that drifted too far out of tolerance. I left the perfectly good & strong 1L6 in place while I did all the repairs and testing, and by the end of the repairs the tube was toast from all the on/off cycles. I went so far to put a 1R5 on the bench to swap them out before I started, but I completely forgot to. I feel your pain.
Thanks for going the extra mile, Shango. And, IMO, it doesn't matter who will be the next leader. When the financial gets fixed, we might make it, but I don't see that happening. Cheers on the diagnostics.
Great video man. The longer the better, and very educational also. About mistakes thats real life and it happens to all of us. From mistakes we learn, so yours make us avoid ours. You are the one and only in this field which such a rich combination of virtues! Thanks.
There are a number of creators i watch that recently are just not having an easy time fixing things or they are beyond repair, collateral damage occurs. It’s weird how it really seems to be a wave of difficulties. Makes me feel better about some things i have not been able to fix but also shows me how much random chance there is in repairing old stuff.
You didnt waste our time. We learned thst tube doesnt work in this radios circuit. I appreciate your honesty and ethics. It was a learning experience for all lf us as well.
Yeips! That poor expensive pair of flush cutters! Been there done that, TWICE! IIRC, in order to replace a 1L6 with a 1R5 you have to disconnect / rewire one of the pins. Those tubes are rated at 1.4 nominal, but they have to withstand a bit more as with fresh batteries the filament voltage will get up to about 1.6 volts per tube. Fresh carbon/zinc batteries will deliver a bit more than 1.5 volts, during most of their life they will stablize at about 1.4 volts. Fresh alkaline batteries can get as high as 1.6 volts, and remain close to 1.5v for most of their life before dropping down to below 1.3 volts near end of life. Hum could be due to reverse leakage of the Se rectum frier. Scope would confirm that.
I'm really glad you posted this. I have this chassis in a Flip Front that has a blue plastic case in great condition. The dial stringing looks scary but still working. I haven't powered it up or done anything else with it yet because it has the same waxy mess on the bottom plate. Thanks for this one.
Great resurrection video for those following at home for how to go about getting a really busted up radio to become a working radio again. Pay close attention to most of those rotten components which can kill any of those tubes easily if they are bad enough. This circuit uses the tubes listed and do not make any substitutions. The circuit diagram says if any part of the radio circuit is grounded (improperly to chassis ) a hum will result. I agree about stated politcal observations you made as the news media is almost pushing the California governor into their camp to get rid of this weak corpse of a "leader". No successful devil can look ugly as he wouldn't be popular in this visual age. Got to have someone that checks all of their boxes.
At the end of the video you seem to imply that changing the heater voltage (and thereby emission) on the 1L6 by a mere 0,05V (1,09 to 1,14V IIRC) makes for a sharp turn on/off threshold on the LO. Now while that may be possible I'd like to offer another explanation; the heaters are the cathodes and in the series heater string configuration each cathode thus observes a different DC cathode bias to ground, made up by the sum of filament voltages downstream. So with the 1L6 having the 1S5 1U4 and 3V4 downstream a change in heater voltage of 50mV on the 1L6 would also cause a similar change in heater voltage on the previous 4 filaments (3V4 counting as two 1,4V filaments). So the DC cathode bias on the 1L6 would rise by 200mV for a 50mV change seen in its heater voltage. And I think this shift in DC cathode Bias is what is causing the turn on/off of the LO, not so much the change in cathode emission in the 1L6 due to +/- 50mV heater voltage.
The G503 schematic, especially the power supply, looks almost exactly like that of the Zenith 500 and 600 series Transoceanics, save for the bandswitch circuitry for the shortwave bands and tone control circuitry. And every T/O I've ever restored has had a little hum after restoration. Whether it's because of the non-inductive electrolytic Zenith refers to, I have no clue. The hum would probably get better after you mount the new capacitors inside the can instead of having them hang under the chassis. Also, a properly repaired antenna and alignment would help a great deal with the hum. If you decide to go further with the radio, I also suggest replacing the selenium rectifier and 130 ohm sand resistor with a 1N4007 in series with a 5 watt, 180 ohm resistor. That should get your filament voltages right on the money. Also, you can use the 1R5 in place of the 1L6 if you cut pin 5 off the 1R5.
Dear shango, Your videos are soothing when I watch them through sleepless nights. My similar hobbies have become vanity, no strive to act anymore. But your energy and devotion to things I once liked make me, at least, have a nap with headphones listening to your calm voice speaking about what I once liked. Thank you, and may you have many more projects!
I really enjoy your videos and trouble shooting methods. Don't change anything please... Seeing how things goes at times for you makes me feel better when things goes wrong for me when I'm tinkering on something goes poof! Thanks for your efforts, sorry for the cost of the tube. Maybe things would have went better if a few airplanes would've been flying around...
These vacuum tube portables always make me think of that "Itsy Bitsy Teeny Weeny Yellow Polkadot Bikini" song, for some reason. But, anyway, this need for $100 tubes to fix $10 radios is becoming more of a problem and the only thing I can imagine easing the pain is a modern-day equivalent of Fetrons: plug & play tube substitutions that were made by Teledyne (the Water Pick people) back in the day. I can imagine a cottage industry springing up to make such things.
You really cannot hot swap that series of tubes. They will blow the filament. Also at 1.25v a 1l6 won't oscillate. Common in trans oceanic. Many are replaced without checking the set operating voltage.
I so want to see you wearing that Zenith badge on a chain. Make sure you polish it real nice first. Maybe add some gold teeth to the chain for authenticity.
Some years ago I bought online a set of solid state drop in replacements for a 600-series Transoceanic; for the entire tube lineup. It was not cheap, I think in the neighborhood of $150 for the whole set, BUT, it means no longer having to worry about fragile 1v filaments and should last me forever. My reason for trying them was intended to see which "tubes" (real versus solid state) would give the best battery life performance but I never got around to building a battery pack to go further with the idea. Believe the maker now sells on eBay as "solidstatetubes" but back in the day had his own website instead. Now, I know people are going to say "why spend that kind of money on a beat up resurrection project?" but you could take the solid state tubes back out afterwards and use them in other projects indefinitely.
I have been running my set in a 600-series TO since Dec 2014, no problems so far. Also haven't noticed any change in performance or audio tone/quality with solid state tubes versus the originals. I am sure the purists will complain about solid-state-afying a tube radio but then there's a similar approach to transistorizing 01A 3-dialer sets thats been around since the 1990s (lets you run a 3 dialer off a 9v smoke det battery iirc).
Thanks! It came up when I Googled "solidstatetubes" . I was hoping someone sold something like that. I have an RCA portable that I bought tubeless for $10 and this might help me get it working for a reasonable price.
I've NEVER seen one of these "Flip Top" Zeniths that are NOT cracked. I think I read somewhere that its a bit of a design issue. There's no way you can fully control the 'down' flip. Eventually, the user is careless and it'll flop down and the dial cover hits the knobs. However, when it's flipped up, it is indeed a great receiver. It gets the antenna coil above the radio chassis. I was able to receive both WSM-AM 650 Nashville and WWL-AM 870 New Orleans in Dallas on one of these (660 and 507 miles). I would not have caught that 1L6 - 1R5 error. But now I know how it's done.
Since you had a dim bulb in circuit you can get away with pulling tubes when the set is on. If running straight off the line, pulling a tube can cause failure of other filaments when the tube is reinserted. Yikes. Sorry about your 1L6, I wish I would have been prescient enough to buy several sleeves of 1L6 tubes in the late 60s when they were $1.75. *sigh*
Should use a shear type cutter, not the normal type pinching pliers. Too much shock. Or, better yet, use a dremel with cutter wheel, while holding the pin with small vice grips. Have your friend or wife hold tube to catch! LOL
@@shango066will you be doing another video on this? I ran into the same exact problem with a Stromberg Carlson awp8 including when I turned the chassis over I had a short and now,a hum and no oscillation. Before this, it would work and than turned off then back on and it would not have any oscillation. This happened after I recapped the tuner section. I’m a long time subscriber and have learned a lot from you. Thanks!
that 'suspect' resistor likely got fried when a filament lower down the chain or the lower part of the dual filament went open, it'd get the entire filament current running through it, which at 680 ohm would be approx 1.5 watts, so not surprised it discoloured and went high...
I was always told to remove everything from pin 5 of the 1L6 tube socket and tie them together without connecting them to the socket pin. THEN the 1R5 tube will work.
I'm glad you leave the mistakes in, it's only human to make mistakes once in a while. The lesson learned here is to double check the internet - Sometimes things aren't the way they're told here.
I wonder if the hum is the selenium rectifier acting up - such as not switching off when it should. (or perhaps switching too quickly and creating noise). It would be interesting to put a standard diode in series with it and see if that helps the hum.
Love your cap tester, allied knight was in Chicago which I love close to. I also have it. But I just got a sico model 76 at an antique store. It's a signal tracer and RC bridge. Think I'm going to add a speaker to it as it only uses the magic eye when in tracer mode.
I actually recently found one of those Motorola battery radios you have had on a previous video, and I picked up radio stations from LA and Sacramento at night with it and I live in the Vancouver BC area. Amazing DXr :-)
As for substantive comment about the subject at hand, it is very informative to see hands-on diagnosis and repair of these 1-volt sets. There are a LOT of them still existing out there, languishing in basements, like mine. Would like to see a follow-up.
the UK company Murphy made 2 'flip front dial' portables, B229 battery only, and BA228 mains battery, used the newer 0.025a filament valves/tubes , no RF stage but had push pull output, 2 DL96/3C4 outputs, so had good oomph compared to single output sets , i dont know of any other UK brands that did one, but possible theyre were some..
the murphy mains battery used paralleled filaments with mains transformer, so had isolated chassis, the 0.025amp filament types are far more sensitive to correct voltage, if parallel fed, or current if series fed, than the 0.05amp types, very easy to pop them, or at best ruin emission, if too high, and emission drop off on well used ones if too far under run
Odd that Zenith would use a 1L6 as the oscillator on that radio. An important point: Never unplug/plug in the tubes on this radio or a Transoceanic while it's powered up. The 9 volt filament voltage across that filament capacitor will rise to a high voltage due to the open filament circuit, and when you plug a tube back in, one of the filaments will blow. If you're lucky, it won't be the 1L6.
The 3V4 audio output tube will use the full 3 volts across the filament when the radio is used on 120volt AC operation. Now, when you use this radio on batteries and plug in the AC cord into the chassis or the radio the 3V4 will only use the 1.4 volts as the rest of the 1.4 volt tubes. FYI,
Wow! I learned more from your mistakes than from any training! You are truly teaching by talking thru your trials and errors and puzzlements. I was with you every step, every confusion. Nice tight photography throughout, so we can actually see every detail of what you do. Is your camera head-mounted? Great work. Thank you!
Purportedly, Zenith built and offered these because of an outcry by Zenith's (CEO) yaught buddies crying about Zenith not offering such a radio. 😊 38:27 .....Me, I've often thought and believed Zenith used Voo Doo in their circuit designs......like tying all of the cathodes and bypass cathode resisistors & caps together as though they were common ground, but no ground was actually used.
I have one of these that don't work but I re upholstered it and made a fake battery that has a modern radio inside. Love this radio even though it is a shelf queen.
Introducing the Zenith Portable Buzzomatic. I wonder why the mains filter hum is so bad, even with the Goliath electrolytic it seemed to be there somewhat. Could it be front end pick up or the fact that the new caps are paralleled with the old filter caps and they are very leaky and pulling down the voltage perhaps? May account why the filament voltage is a little low. Just a wild guess, would be great to see this revisited and sorted for the desert test, but I guess that will be on batteries. Great vid as always, best regards from across the pond.
The 1R5 will not work in my Trans Oceanic. I was so happy that I could use a substitute when I looked it up online, but it will not, and the cheapest 1L6 is around $50 on line 😢
I'm not sure if this has been mentioned in the previous comments, just clip pin 5 off the 1R5 if needed in your circuit. I read about clipping pin 5 years ago on the Antique Radio Forums. I used a clipped 1R5 in place of the 1L6 in a RCA portable for years.
You can upgrade the selenium half wave rectifier .. put in a (full wave) bridge rectifier, and then, put in a series of microwave/HV diodes as needed to get the proper B+ voltage.
@@shango066 It seemed with new electrolytics should have smoothed out that buzzing. It's when you placed that huge 3500uf cap across, that totally cleaned it up. Also, when you placed the diode across the selenium, the voltage climbed, but would need a different value current resistor. I still think maybe the selenium rectifier is weak, and could be checked with the scope for excess ripple. Just a thought. Very good video Shango. 👌
I purchased a solid state 1L6 replacement unit around 15 years ago. It performs well on the transoceanic receivers on all bands. It's mounted to a conventional 7 pin arrangement, a direct plug in. Now for a life test! Looking forward to the next dx session. BTW could the output tube cause that hum? Just a thought............
be warned there was a DL98/3B4 that doesnt have filament on pins 1 and 7 , its 4 and 5 with tap on 6, but it wasnt a normal domestic radio type so unlikely to find them used for those sort of sets ,i think it was intended for rf power output
In these kind of portable radios made in EU they use the 1.5V battery as capacitor/zener for stablize the heaters voltage... so if you test a radio without the rechargabe battery you will burn the tubes... Check the schematic of this one for being sure and not frying tubes...
The thing I love about your videos is your honesty. You own it if you make mistakes, and that is refreshing. Many of us could have made the same mistake and it makes it more believable to see the videos with the mistakes included.
Your pain is our gain. Don't beat yourself up. Great video as always, and I always learn something.
No "time wasted" Here. Shows how your mistakes help you learn. Much better than just giving the answer. Great video!
Love your videos. You and BIGCLIVE encouraged me to return to electronic tinkering. And love the kitty - mine sleeps on my workdesk, leaving fur balls.🐈🐱
I have my great uncle's 1954 Zenith am fm phonograph console in a beautiful cherry wood cabinet. The phonograph has the Cobramatic turntable. It all works great! I inherited it when he passed in 1994 at age 100! Since ive had it 30 years next April, its had no issues, it always plays fantastic, 0 hum, the original speaker sounds very good, all the tubes except for one, are Zenith. It will be 70 years old next month. Records play fine too. People have told me i should have it rebuilt, its a ticking time bomb for a catastrophic failure....i keep close tabs on it when using it, and i do use it several times a month, few hours each time. But it just seems perfectly fine! Even the dial light works, along with the little amber light at the bottom of the cabinet to let you know its on, if the cabinet is all closed up.
Interesting work. I have a few battery tube portables, RCA Zenith and Stromberg-Carlson, all with tuned RF stages, and enjoy listening to them. We all "screw up" from time to time. I pulled an electrolytic can on the horizontal sweep chassis of a 1948 RCA projection TV, restuffed it, and remounted it wrong on the phenolic mounting wafer. Glad I caught it before smoke was released LOL . I've been at it for 62 years, reparing my first radio at 10, a simple line cord replacement, but it created a life long interest in vintage electronic restoration and repair. Thank You very much for the video of the Zenith restoration ! 😊
Thank you Shango, for showing us that even the guys who really know what they are doing experience frustrations and dead ends. Very encouraging for those of us who are still climbing the knowledge ladder!
I restored one of these two years ago. It’s a pretty ordinary AA5 radio, but it has an RF stage, which is great. The appeal of this radio is the very thing for which it might be criticized. The “flip-up” dial is very cool, as is the instant-on switch, BUT all of that complexity comes at a price. The antenna wire is vulnerable to breaking (from metal fatigue due to opening and closing), the on-off switch mechanism is prone to failure (plastic fatigue), and the clear dial cover glass (plastic) is almost always cracked (due to hitting the knobs when closing it). All that said, mine is a beautiful example and, once restored, is an excellent performer and addition to my collection.
Thanks again Shango, I really like the longer videos. I've honestly learnt more from you and your videos than anyone else. I love the diagnosis and honesty when you make a mistake. It really makes me feel better knowing it's not just me! I'm on to my 4th tube set restoration and dozens of transistor sets behind me. Don't think I'd have got there without this videos. Thanks for all the effort, it is appreciated 👍
So, apparently, the legendary, zenith quality was so strong that the damn amp works with no tubes!!!
Only Zenith is good enought 😂
It'll probably work without power to the components.
It can gather power from the multiverse.
Those 1.4V directly heated filament tubes were originally designed for battery use. Back in the day, firms like Ever-Ready (UK market at least) made a combined battery which had both 90V HT and 1.5V LT sections.
The filament cathodes are very sensitive to ripple in their supply. I've found just the same when making battery eliminators for these sets.
I won't be surprised if that radio hummed like a Banshee from new when run from the mains.
Hummed like a banshee. I'm adding that one to my dictionary. 😅
nope. they are very hum free. i have about 7 that are all very quiet, main or battery. I run the A battery with 7 cells, instead of the recommended 8. But, I have one lunchbox model (forget the model) that has the same identical hum problem. It plays fine, but just fuzzy hum. I finally gave up on it.
Love how you have tubes in a bag that are all same voltage for the heaters. I have mine in a plastic shoe box but they take up too much space. So I just got some ultra thick plastic zip bags and you get the rest..... thanks shango066 love all your videos. Even the eol or look how many transistors my radio has
My brother had a radio from this era..little did he or I know that even if it runs on batteries the voltages inside
can kill you,if the right conditions exist
Plus these radios weighed a ton and the batteries only lasted a few hours (carbon zinc poo poo)
But
You were 'The Guy" to be invited to parties and camping because you could play some Rock 'n Roll!
Defy your parents,the Church and all your teachers and neighbors,you were a REBEL
Don't worry about a long video. I love them! I learn, relax and enjoy. Thank you so much.
Original Magnum P.I. theme. That brings back memories.
Actually is the 2nd theme for the show.
@@blazertracer1 Meaning the original series. Not that fumble fangled reboot.
I never really liked the intro theme in season 1.
@akshonclip8149 the original series had 2 theme songs. 1st season for the first 7 to 10 episodes had a different theme then afterwards the one everyone knows.
I have an H500 T-O I restored probably 10 years ago, but a couple years back it started acting up with SMD and AVC issues from a few resistors that drifted too far out of tolerance. I left the perfectly good & strong 1L6 in place while I did all the repairs and testing, and by the end of the repairs the tube was toast from all the on/off cycles. I went so far to put a 1R5 on the bench to swap them out before I started, but I completely forgot to. I feel your pain.
Another hour + shango video. I won’t get anything done today 😂
Thanks for going the extra mile, Shango. And, IMO, it doesn't matter who will be the next leader. When the financial gets fixed, we might make it, but I don't see that happening. Cheers on the diagnostics.
Great video man. The longer the better, and very educational also. About mistakes thats real life and it happens to all of us. From mistakes we learn, so yours make us avoid ours.
You are the one and only in this field which such a rich combination of virtues! Thanks.
Totally.....
There are a number of creators i watch that recently are just not having an easy time fixing things or they are beyond repair, collateral damage occurs. It’s weird how it really seems to be a wave of difficulties. Makes me feel better about some things i have not been able to fix but also shows me how much random chance there is in repairing old stuff.
You didnt waste our time. We learned thst tube doesnt work in this radios circuit. I appreciate your honesty and ethics. It was a learning experience for all lf us as well.
Still learning every time I check out your feed ! Tools let me down too ! Keep up the good work!
Yeips! That poor expensive pair of flush cutters! Been there done that, TWICE!
IIRC, in order to replace a 1L6 with a 1R5 you have to disconnect / rewire one of the pins.
Those tubes are rated at 1.4 nominal, but they have to withstand a bit more as with fresh batteries the filament voltage will get up to about 1.6 volts per tube. Fresh carbon/zinc batteries will deliver a bit more than 1.5 volts, during most of their life they will stablize at about 1.4 volts. Fresh alkaline batteries can get as high as 1.6 volts, and remain close to 1.5v for most of their life before dropping down to below 1.3 volts near end of life.
Hum could be due to reverse leakage of the Se rectum frier. Scope would confirm that.
I'm really glad you posted this. I have this chassis in a Flip Front that has a blue plastic case in great condition. The dial stringing looks scary but still working. I haven't powered it up or done anything else with it yet because it has the same waxy mess on the bottom plate. Thanks for this one.
Great content and humility showing where wrong information can lead us astray
Great resurrection video for those following at home for how to go about getting a really busted up radio to become a
working radio again. Pay close attention to most of those rotten components which can kill any of those tubes easily if
they are bad enough. This circuit uses the tubes listed and do not make any substitutions. The circuit diagram says if any
part of the radio circuit is grounded (improperly to chassis ) a hum will result. I agree about stated politcal observations
you made as the news media is almost pushing the California governor into their camp to get rid of this weak corpse of
a "leader". No successful devil can look ugly as he wouldn't be popular in this visual age. Got to have someone that
checks all of their boxes.
Love waking up to Shango this Saturday morning learn something new and love to watch million thanks
"Leakier than a twink on Epstein island" I'm dying 😂😂
OMFG!
The "63-2018" asbestos-sand resistor is very interesting!
Your analogies are Legend bro. Make happy sunshine. 🖒
At the end of the video you seem to imply that changing the heater voltage (and thereby emission) on the 1L6 by a mere 0,05V (1,09 to 1,14V IIRC) makes for a sharp turn on/off threshold on the LO. Now while that may be possible I'd like to offer another explanation; the heaters are the cathodes and in the series heater string configuration each cathode thus observes a different DC cathode bias to ground, made up by the sum of filament voltages downstream. So with the 1L6 having the 1S5 1U4 and 3V4 downstream a change in heater voltage of 50mV on the 1L6 would also cause a similar change in heater voltage on the previous 4 filaments (3V4 counting as two 1,4V filaments). So the DC cathode bias on the 1L6 would rise by 200mV for a 50mV change seen in its heater voltage. And I think this shift in DC cathode Bias is what is causing the turn on/off of the LO, not so much the change in cathode emission in the 1L6 due to +/- 50mV heater voltage.
Bingo
Just started watching. I hope it has a happy ending!
The G503 schematic, especially the power supply, looks almost exactly like that of the Zenith 500 and 600 series Transoceanics, save for the bandswitch circuitry for the shortwave bands and tone control circuitry. And every T/O I've ever restored has had a little hum after restoration. Whether it's because of the non-inductive electrolytic Zenith refers to, I have no clue. The hum would probably get better after you mount the new capacitors inside the can instead of having them hang under the chassis. Also, a properly repaired antenna and alignment would help a great deal with the hum. If you decide to go further with the radio, I also suggest replacing the selenium rectifier and 130 ohm sand resistor with a 1N4007 in series with a 5 watt, 180 ohm resistor. That should get your filament voltages right on the money. Also, you can use the 1R5 in place of the 1L6 if you cut pin 5 off the 1R5.
Dear shango,
Your videos are soothing when I watch them through sleepless nights. My similar hobbies have become vanity, no strive to act anymore. But your energy and devotion to things I once liked make me, at least, have a nap with headphones listening to your calm voice speaking about what I once liked. Thank you, and may you have many more projects!
Love your choice of music dude. Lol
Thanks! Just to help out a bit, keep on truckin.
I really enjoy your videos and trouble shooting methods. Don't change anything please... Seeing how things goes at times for you makes me feel better when things goes wrong for me when I'm tinkering on something goes poof! Thanks for your efforts, sorry for the cost of the tube. Maybe things would have went better if a few airplanes would've been flying around...
These vacuum tube portables always make me think of that "Itsy Bitsy Teeny Weeny Yellow Polkadot Bikini" song, for some reason. But, anyway, this need for $100 tubes to fix $10 radios is becoming more of a problem and the only thing I can imagine easing the pain is a modern-day equivalent of Fetrons: plug & play tube substitutions that were made by Teledyne (the Water Pick people) back in the day. I can imagine a cottage industry springing up to make such things.
Excellent video. Encouraging to know even pros make mistakes.
You really cannot hot swap that series of tubes. They will blow the filament. Also at 1.25v a 1l6 won't oscillate. Common in trans oceanic.
Many are replaced without checking the set operating voltage.
Yes. shango and shabbat go well together. Definitely the envy of most every man.
I so want to see you wearing that Zenith badge on a chain. Make sure you polish it real nice first. Maybe add some gold teeth to the chain for authenticity.
Cut pin 5 on the 1r5 tube, it will work fine in that receiver.
Thanks for the video, certainly not a waste of time. I admire your honesty
You're my favorite radio tech, by far.
You gave it your best shot to revive that tired old radio. It's destiny will be in the recycle for any metal value
Wow I was expecting that selenium to bust its bag when you put that monster electrolytic in circuit!
I thought that would happen almost immediately too. Was surprised when it didn't go up in smoke.
SMOKED.
More white-knuckle excitement from Shango..... another weird and wonderful troubleshoot adventure....
That fat black wire running under the rectifier? Original routing?
Would a full resto redeem your investment? After all... Zenith... stellar DXer.....
Excellent! I three tip top Zeniths that I will be combining into one. Glad you left the part in with you riding in the short bus.
There will be a follow-up video that addresses some interesting stuff
33V ripple with 70V on the filter cap 😂... great video as always mate..
Regards from across the pond 😎👍
Steve
Some years ago I bought online a set of solid state drop in replacements for a 600-series Transoceanic; for the entire tube lineup. It was not cheap, I think in the neighborhood of $150 for the whole set, BUT, it means no longer having to worry about fragile 1v filaments and should last me forever. My reason for trying them was intended to see which "tubes" (real versus solid state) would give the best battery life performance but I never got around to building a battery pack to go further with the idea. Believe the maker now sells on eBay as "solidstatetubes" but back in the day had his own website instead. Now, I know people are going to say "why spend that kind of money on a beat up resurrection project?" but you could take the solid state tubes back out afterwards and use them in other projects indefinitely.
Done
I have been running my set in a 600-series TO since Dec 2014, no problems so far. Also haven't noticed any change in performance or audio tone/quality with solid state tubes versus the originals. I am sure the purists will complain about solid-state-afying a tube radio but then there's a similar approach to transistorizing 01A 3-dialer sets thats been around since the 1990s (lets you run a 3 dialer off a 9v smoke det battery iirc).
Thanks! It came up when I Googled "solidstatetubes" . I was hoping someone sold something like that. I have an RCA portable that I bought tubeless for $10 and this might help me get it working for a reasonable price.
@@sgath92 I'm currently testing them and I found an issue. It will be in a rather long video coming up in the near future
I am all for the long duration video formats, can't wait to see what it is.
I've NEVER seen one of these "Flip Top" Zeniths that are NOT cracked. I think I read somewhere that its a bit of a design issue.
There's no way you can fully control the 'down' flip. Eventually, the user is careless and it'll flop down and the dial cover hits the knobs.
However, when it's flipped up, it is indeed a great receiver. It gets the antenna coil above the radio chassis. I was able to receive both WSM-AM 650 Nashville and WWL-AM 870 New Orleans in Dallas on one of these (660 and 507 miles).
I would not have caught that 1L6 - 1R5 error. But now I know how it's done.
Since you had a dim bulb in circuit you can get away with pulling tubes when the set is on. If running straight off the line, pulling a tube can cause failure of other filaments when the tube is reinserted. Yikes. Sorry about your 1L6, I wish I would have been prescient enough to buy several sleeves of 1L6 tubes in the late 60s when they were $1.75. *sigh*
That complex heater circuit phew!
I saw that exact same radio on an old black-and-white Laurel and Hardy movie back from the 1951
Love the magnum pi theme song
In many radios OTHER THAN the Trans-O's, you need to disconnect pin 5 to use a 1R5(or just clip the pin off the tube).
Ahhhhh lets try it
Should use a shear type cutter, not the normal type pinching pliers. Too much shock. Or, better yet, use a dremel with cutter wheel, while holding the pin with small vice grips. Have your friend or wife hold tube to catch! LOL
@@shango066will you be doing another video on this? I ran into the same exact problem with a Stromberg Carlson awp8 including when I turned the chassis over I had a short and now,a hum and no oscillation. Before this, it would work and than turned off then back on and it would not have any oscillation. This happened after I recapped the tuner section. I’m a long time subscriber and have learned a lot from you. Thanks!
@@robertriley5352 yes
that 'suspect' resistor likely got fried when a filament lower down the chain or the lower part of the dual filament went open, it'd get the entire filament current running through it, which at 680 ohm would be approx 1.5 watts, so not surprised it discoloured and went high...
I was always told to remove everything from pin 5 of the 1L6 tube socket and tie them together without connecting them to the socket pin. THEN the 1R5 tube will work.
I'm glad you leave the mistakes in, it's only human to make mistakes once in a while. The lesson learned here is to double check the internet - Sometimes things aren't the way they're told here.
I wonder if the hum is the selenium rectifier acting up - such as not switching off when it should. (or perhaps switching too quickly and creating noise). It would be interesting to put a standard diode in series with it and see if that helps the hum.
Love your cap tester, allied knight was in Chicago which I love close to. I also have it. But I just got a sico model 76 at an antique store. It's a signal tracer and RC bridge. Think I'm going to add a speaker to it as it only uses the magic eye when in tracer mode.
I actually recently found one of those Motorola battery radios you have had on a previous video, and I picked up radio stations from LA and Sacramento at night with it and I live in the Vancouver BC area. Amazing DXr :-)
KOMO in Seattle comes in most every night down here in Los Angeles, faint but usually listenable.
As for substantive comment about the subject at hand, it is very informative to see hands-on diagnosis and repair of these 1-volt sets. There are a LOT of them still existing out there, languishing in basements, like mine. Would like to see a follow-up.
Thanks for sharing your videos with us! I enjoy.
When you said you were going to hit bypass, my heart stopped for a second. LOL.
the UK company Murphy made 2 'flip front dial' portables, B229 battery only, and BA228 mains battery, used the newer 0.025a filament valves/tubes , no RF stage but had push pull output, 2 DL96/3C4 outputs, so had good oomph compared to single output sets , i dont know of any other UK brands that did one, but possible theyre were some..
the murphy mains battery used paralleled filaments with mains transformer, so had isolated chassis, the 0.025amp filament types are far more sensitive to correct voltage, if parallel fed, or current if series fed, than the 0.05amp types, very easy to pop them, or at best ruin emission, if too high, and emission drop off on well used ones if too far under run
Odd that Zenith would use a 1L6 as the oscillator on that radio.
An important point: Never unplug/plug in the tubes on this radio or a Transoceanic while it's powered up. The 9 volt filament voltage across that filament capacitor will rise to a high voltage due to the open filament circuit, and when you plug a tube back in, one of the filaments will blow. If you're lucky, it won't be the 1L6.
that's so Cool dude, you Knew the oscillator would start~!
The 3V4 audio output tube will use the full 3 volts across the filament when the radio is used on 120volt AC operation. Now, when you use this radio on batteries and plug in the AC cord into the chassis or the radio the 3V4 will only use the 1.4 volts as the rest of the 1.4 volt tubes. FYI,
Love the short bus to Walmart reference lol
Wow! I learned more from your mistakes than from any training! You are truly teaching by talking thru your trials and errors and puzzlements. I was with you every step, every confusion. Nice tight photography throughout, so we can actually see every detail of what you do. Is your camera head-mounted? Great work. Thank you!
Be cautious when testing 1 volt tubes. Some testers put out too high of a filament voltage. I wonder if that's why so many opens.
Some older ohm meters can damage tube filaments .
Also coils for that matter !
Purportedly, Zenith built and offered these because of an outcry by Zenith's (CEO) yaught buddies crying about Zenith not offering such a radio. 😊
38:27 .....Me, I've often thought and believed Zenith used Voo Doo in their circuit designs......like tying all of the cathodes and bypass cathode resisistors & caps together as though they were common ground, but no ground was actually used.
I've worked on some sets similar to this set and yes,they can be a bit of a pain lol.The tubes are so sensitive and too easy to destroy.
I have one of these that don't work but I re upholstered it and made a fake battery that has a modern radio inside. Love this radio even though it is a shelf queen.
Introducing the Zenith Portable Buzzomatic. I wonder why the mains filter hum is so bad, even with the Goliath electrolytic it seemed to be there somewhat. Could it be front end pick up or the fact that the new caps are paralleled with the old filter caps and they are very leaky and pulling down the voltage perhaps? May account why the filament voltage is a little low. Just a wild guess, would be great to see this revisited and sorted for the desert test, but I guess that will be on batteries. Great vid as always, best regards from across the pond.
It was definitely challenging. But don't despair. You can easily design and sell tube based nuclear weapons😉
Hi gentlemens , happy weekend
The 1R5 will not work in my Trans Oceanic. I was so happy that I could use a substitute when I looked it up online, but it will not, and the cheapest 1L6 is around $50 on line 😢
you must carefully cut off pin 5, then it will work on BC bands
Febreeze with burning selenium rectifier scent hahahaha 😆
Leakier than a what on whose island? lmaoooooo!
I'm not sure if this has been mentioned in the previous comments, just clip pin 5 off the 1R5 if needed in your circuit. I read about clipping pin 5 years ago on the Antique Radio Forums. I used a clipped 1R5 in place of the 1L6 in a RCA portable for years.
24:10 Epic
58:16 Should be plenty of therapists available in Kallifornea
I have the brick red one, plays very well and is a great performer, this also uses the hard to find 1L6 ....I think the 1R5 will work
12:22 I bet that chassis is hot. ⚡️Where’s Mr Carlson, Mr Carlson.
Thanks I started watching this at 14 comments and now it is at 53 comments not counting this one.
The "Tip Top"! Also came in a plastic cabinet.
You can upgrade the selenium half wave rectifier .. put in a (full wave) bridge rectifier, and then, put in a series of microwave/HV diodes as needed to get the proper B+ voltage.
Gotta wonder how good that selenium rectifier is, and wether or not it's letting too much ripple through ? Just a guess.
I thought I changed it? And the capacitors should catch that and smoke the sand resistor
@@shango066 It seemed with new electrolytics should have smoothed out that buzzing. It's when you placed that huge 3500uf cap across, that totally cleaned it up.
Also, when you placed the diode across the selenium, the voltage climbed, but would need a different value current resistor. I still think maybe the selenium rectifier is weak, and could be checked with the scope for excess ripple. Just a thought. Very good video Shango. 👌
I would also bet the selenium is letting in reverse current....
I purchased a solid state 1L6 replacement unit around 15 years ago. It performs well on the transoceanic receivers on all bands. It's mounted to a conventional 7 pin arrangement, a direct plug in. Now for a life test! Looking forward to the next dx session.
BTW could the output tube cause that hum? Just a thought............
Your videos are awesome, by the way.
@ 12:10 Because it doesn't know the words.....
be warned there was a DL98/3B4 that doesnt have filament on pins 1 and 7 , its 4 and 5 with tap on 6, but it wasnt a normal domestic radio type so unlikely to find them used for those sort of sets ,i think it was intended for rf power output
For missing tubes, look up soviet rod tubes like 1Ж24Б
I love this channel
dont think 1L6 types were ever used in a UK made battery set, usually the DK91/1R5 or DK92/1AC6 for the 0.05a types, DK96/1AB6 for 0.025a
Ok, who else besides me watched this one from end to end?
In these kind of portable radios made in EU they use the 1.5V battery as capacitor/zener for stablize the heaters voltage... so if you test a radio without the rechargabe battery you will burn the tubes... Check the schematic of this one for being sure and not frying tubes...