I was recently gifted a Tektronix 2235 and just finished this first video and wanted to say thank you so much for a easy to understand approach. I actually take notes in a graph composition notebook. I'm 53 and wish I started sooner but I am doing it now. Thanks again.
Been an audio engineer for 30 years (live sound, touring) and am just now getting into learning about this stuff. I was on it as a pre teen back in the 80's but got more interested in other aspects of the field. Now I've got some old reel to reel machines (Nagra IV-SJ x 2) I'm using to record the band I mix and those need maintenance so, off we go. Tektronicx 465 Purchased and now, thanks to you I'm looking forward to starting this journey of learning to care for my tools. Thank you.
Thanks so much for taking the time to do this series. Extremely helpful for the likes of myself who hasn't used a scope in more than 60 years. Best wishes to you and your family for a healthy, happy, and prosperous new year.
My man. I just love your channel so much. It's packed with such useful, practical and well presented material. I'm fairly confident that you're content has put a lot of bread on the table for mini folks and I hope you're being well supported by them.
Simply the best presentation on the How, What and Why of an Oscilloscope and accessories for the audio bench. Straightforward, practical and understandable. Mark you're the best! Thanks for sharing your expertise and time. I am getting back into vintage electronics and have discovered your videos as my main source of education. Thank you. Thank you. Thank you!
Been in electronics for 50 years and just learned that I can still learn new things. I have the same isolation xfrmr and never thought to plug in a power strip. I am going to do this and paint it red and next to it the other will be it's natural silver. Great tip.
Perfect, it's the last bit i have to aquire to begin the real work on the audio signal. I've been playing too long with swapping parts now it's time to really see what they're doing in the circuit. Thank !
Is your dog part Chihuahua? Best way to learn electronics is in college. DC, AC, Electronics 101 to 103. No time for college? Then learn: Ohms Law, kirchhoff Voltage and Law, Thevenin's Theorem Albert Malvino "Electronic Principles" is a really good book. Hook up the example circuits in each chapter and test them with your equipment. You will soon be designing your own audio amplifiers using discrete components.
@@JohnDoe-bf1fw Actually, I have a 3 yr College degree in Electronics... but didn't work at the component level for long, and don't recall doing much related to AC, other than motors and such. My dog was a Welsh Corgi.
In ancient times when I worked at Tektronix, I used a 464 analog scope (I think that was the model). I learned to use it very well and loved it. A couple of years ago, I purchased (used) a Tek TDS420A digital scope with CRT display. Someday I might get it figured out. Like you, I grew up on the analog scopes and am struggling to get up to speed on all the menus, functions, etc., that my digital scope had. I just need to live long enough!
I can tell that you have many years of experience and knowledge of electronics as you explain things so well. Even though I use an o'scope and sig gen for radio tinkering, I do use audio frequencies when aligning radios. So, your video is very helpful to anyone contemplating purchase and use of an o'scope and a signal generator. Thank you very much.
Great video Mark!!! It may also be worth mentioning to the audience, that Variacs (Autotransformers) are not isolation transformers. Many people think they can double as such. Also, an isolation transformer, although electrically isolated from the line and neutral, is not necessarily isolated from ground. If you are going to use a 1:1 transformer for ground isolation make sure you check that the line side and load side grounds are not the same point electrically. For some, this can be fixed by a simple removal of a ground strap connection or snipping the ground prong on the line-side plug. I have a Tenma 72-1095 Isolation Transformer with adjustable voltage and it has a common ground. The load side plugs are connected to ground via a ground wire to the chassis. Disconnecting this wire isolates the load side. Just something to think about. Thanks!!!
Love this series. Thank you. Concerning the channel selection buttons on that Rigol, that's why I won't buy a Rigol and will be buying a Hantek DSO2D15 which has individual controls for each channel and an internal arbitrary waveform generator. It will be an addition to my Tek 465 scope and if I ever get around to repairing them, my two HP 1741A scopes.
I have and use the exact same isolation transformer you have, and use a power strip out from there for everything, including the variac and sometimes a DBT. I just got one heck of a deal on a brand new Tektronix TBS1104 Digital Oscilloscope: 100MHz, 4 Channels, 1GS/s sample for a mere $600. They sell for over $1900 on most places like Mouser. Santa was good to me. lol! The 4 channel is great when servicing quad amps and receivers. The old analog BK 2120 20MHz scope serves the purpose quite well and will not be "retired" any time soon and will be used on a 2nd bench. The Lab-Volt 1236 AF/RF generator works quite well for audio too. Awesome videos Brother!
I'll sure be following this series. I was given 2 scopes some time ago but not even looked at them, don't even know if they work. Gonna dig them out soon and get my self familiar with them.
Very excited for this series. Been watching your videos for a while now and you are great at explaining what you are showing. Thank you for the time you put into everything you provide us hobbyist with. Happy New Year
Thank you. I watched episode two before one and asked whether analog or digital and was told to watch episode one. Glad I did. Great explanation. I am definitely looking forward to the rest of the series.
Today I found a signal generator and nice HP tube screen Oscilloscope 100MHZ in our local electronics recycling - . the generator has a gear inside broken so that has to be fixed (it can't dial to the comb filter) I think it's a simple fix.. and the HP fired up perfectly and your 3rd part video got me dialed in an confirmed. I'm SO happy to have found these today. I agree with the bench space thing. and I have a spot on the bench for this... my first non computer based osc. Appears my HP has pretty much all the same features as that Tektronik minus 2 less channels - 100MHZ is overkill for audio so that's all good ! I had to jerry rig an adapter..will order one of those packages from amazon you showed. Looks great for $20. I can see some great use out of the modern digital units.. but I too hate accessing so many menus. I'm more of a tactile operator. I can hunker in to the 'interface'..but would prefer not to.
I already own an several oscilloscopes but I enjoyed the video and plan on following along so I can pick up new info as you progress through the lessons.
Great video and good advice. Be sure to also get 50 ohm BNC terminators for your scope inputs to assure that you'll see correct voltage readings from your signal/function generator.
Perfect Timing. I am looking to purchase an Oscilloscope for various Guitar amplifier and pedal builds. Looking forward to watching the series....Thank you.
Thanks Mark. It is about time some body explains this with practical applications. I learned this 40 years ago with out applications. Education is such a bitch. When you get your amp class setup, done I am in. Will see youall in the south..
Very good video, sir. I've ended up with several 'scopes ranging from a late 40s lab model through a dual channel Heathkit c.1970 up to a 100 MHz Techtronics. For audio use on my radios I use the Techtronics or another 10 MHz scope (tube equipment) or one of the cheap DSO138 or DSO150 units from eBay/AliExpress/Bangood for solid state equipment (these are roughly $24 - $30). I have used the DSOs fed through a capacitor for some boat anchors. I plan on closely following the remainder of this series. Thanks.
i used a tek 545 for years and it was a great 33mhz scope with interchangable vertical plugins. In the late 80's that was getting dodgy so I replaced that with 35mhz dual trace Hitachi scope, it was functinality similar to the old 545 and easy to use. The 545 is long gone, the Hitachi is still working great. I 2011 I got a good deal on a Tek 2230 storage scope that is a 100mhz analog scope with a digital overlay and waveform storage. I used a scope like this for years in my real job so i was very familiar with it. I can now display 4 channels on the odd chance i need to do that by using both scopes but that almost never happens. The digital capture comes in handy if your going through parts trying to select something with known risetimes. The modern digital bench scopes are interesting but you should be able to find a good analog scope for a good price and as a bonus you can probably fix it yousrself, if a new digital scope dies it has to go back to be fixed and will be gone for weeks or months and cost a lot to repair. As to the ability to display measured values on the screen i find i can do the math in my head faster than what it takes to set up the fancy scopes.
Looking forward to the rest of your series. Started my tech bench about 2 years ago and went through this entire process without as much guidance. The one area that stopped me cold for a bit was the stupid and mislabeled isolation transformers on the market. Very few are actually isolated. I am not referencing a Variac. They almost all tie the ground blade to the round ground plug that you are expecting to isolate from. I had to learn how to modify a new one by changing out the type of plugs on one bank (there is a special type of isolated outlet plugs you can buy) and removing the round pin ground connection that was originally connected. Everyone that checks their isolation on almost all of these newer ones will be surprised to find they have continuity to the any other wall outlet ground pin. They apparently can call it isolated still because it uses a transformer. It doesn’t have anything to do with ground isolation anymore. Your older isolation model or use of 2 prong adapters is the easiest method to go by.
Agreed. Isolation transformers are sold with safety in mind. The problem, as you stated, is that many iso transformers are not true isolation transformers. You *cannot* blindly trust your life - or test equipment - to an iso transformer. There are a lot of gotcha's involved. You *must* test the thing. Corollary - You must know how to test it.
Great intro series for new learners and old dogs too. Those old 10 to 20 Mhz scope will serve one well, I saw 100 Mhz scopes for as little as $50 dollars a afew days ago on the web.
This is a very helpful video series, I was searching for something like this long time up to now, I respect your work and your time to make this educational video. Thank you!
And it pays to get a good quality meter. Although the "cheapos" do work, they don't work very well after a while and will become intermittent from oxidation on all the contact areas. Areas like the switch contacts and probe sockets where you have to "wiggle" them to regain non-resistance contact. I finally went with Fluke when I could afford them and never looked back. There are other "top shelf" brands as well. I still use my "cheapo" meters a lot for things like "quick" checks and the like to save wear and tear on the Fluke meters.
A thing to keep in mind when purchasing a scope, is how deep is your bench? The older ‘tube’ based scopes, are considerably deeper to accommodate the tube compared to the likes of the newer digital scopes like the Rigol which are the opposite!
I agree whole heartedly. Sadly, because I'm so "old school", I love my Tektronix 2246. I know every button and knob, and like having discrete controls. I do have a Siglent 1104x-e, but haven't come close to mastering it's capabilities nor it's menu system. I also have an HP-54610b with it's memory module, which is an awesome piece of gear.
Since I'm a tube roller guess I'll comment. First of all love your channel thanks for all the info. I just won't work on the amp when it's plugged in. I power the amp down, move my connection, then power it back up. Takes longer but it's a safety step I won't skip often. Also people with isolation transformers need to know they can't use test instruments that way and they are grounded if nearby. Which means also you could touch the ground on the oscilloscope lead when you hook it up to your amp. It takes very little current supposedly to kill a person. Having the amp turned off when moving your connection isn't ever mentioned. The 1 hand rule is impractical. You eventually will inadvertantly have 2 hands in your amp. You can see powering the amp down doesn't take that long. If Working on it powered up MUST wear insulating gloves such as latex, and only one hand if possible.
This is just great! Thanks, Blueglow Electronics. An extra thank you for not saying "one Hurt, two Hertz" :D Most Americans I've heard on RUclips confuse things that way.
I admit, I'm American and just reading comments in most of my subscribed channels is usually frustrating, and honestly embarrassing! As you've probably figured out, our education system is surely lacking, and it must really make Europeans and Asians cringe! I love my country, but we fall way behind in education. ✌😵
great video I have been thinking about starting to learn how to fix my vintage gear for awhile now . Thanks for the info to make my mind up and start gathering the things I need Great video and thank you very much
That family of scopes has a well documented history of problems with the vertical attenuators and a bit of a PITA to work on. OTOH, it is also well known to be a genuine workhorse
I can add a little info on vintage scopes as I have just done some research and testing for model railroaders who might want an oscilloscope for measuring the "Digital Command Control" voltage but don't want to spend much. (Plus, I have used such scopes in my mercilessly long career.) One thing to remember is that the major manufacturers each had a range, often a very wide range, of oscilloscope models and usually the bottom of the line would be fine for audio. But on the used market, there tends to be far less of a price spread between models and manufacturers than for the original price spread. The Tektronix 465 mentioned (or you might be more likely to find the 465B) was a top line oscilloscope (the industry standard, actually) introduced in 1972 for $1,725 ($11,470 in 2021 dollars) sells on eBay for $100 to $250. A Tektronix 2215 introduced in 1982 for $1.400 ($4,032 in 2021 dollars) sells used for $50 to $150. A Hitachi V-212 introduced in 1983 for $340 ($949 in 2021 dollars) sells used for $50 to $120. Of course, offerings vary in condition a lot, but you can get a very nice vintage scope for so little money that the biggest concern might be the shipping cost and perhaps having to buy some probes. If buying a new digital scope, typical names today for bench scopes are Siglent, Rigol, Hantek, and some others. (I recently got a Siglent SDS1202X-E and think it is rather decent.) RUclips reviews abound on new scopes but beware that some reviews are by some who are not very knowledgeable and some by those with decades of electronics training and experience. While the lowest bandwidth models are adequate for audio, it often doesn't cost very much more to get much more bandwidth and perhaps more features. Frankly, the options today for low cost oscilloscopes made in China can make you feel like a kid in candy store. Some scopes I would NOT recommend are the "mini" DSO's or "Tablet" oscilloscopes. While usable, most wildly exaggerate their bandwidth and can be annoying to use with minimal controls and maximum menus so you are forever cursoring, cursoring, and cursing to make changes. Also, even the lowest end mini-DSO (200 kHz claimed bandwidth, but not really) is about $75 and if you step up to a better model and you are above $100 pretty easily. They just aren't a good value in my view. They are the sort of thing that, if want to use it regularly, you live to regret. They do have the advantage of being battery operated, however, which certainly takes care of isolation issues.
Greetings: FYI: As far as I am concerned, all RCA type connectors are to be called "phono" types. They all are single signal (plus shield). They have been around a long time and were originally used to connect the first phonographs with electrical pick-ups to tube radios equipped with a single RCA connector to use the radio's amplifier and speaker to listen to 78 rpm records that had once been played on wind-up gramophones. All tip-ring-sleeve audio connectors owe their heritage to the original plugs used on telephone switchboards, hence "phone" connectors. Although those first phone plugs (and jacks) were three connector types, the audio industry standardized on them for patching including use for balanced signals. My first exposure to tiny plugs/jacks were as earphone jacks on transistor radios. Some were smaller than the common 3.5 mm plugs used today. But all are deserving to be called "phone" plugs. BTW: in Europe RCA phono plugs are often referred to as CINCH plugs as CINCH JONES is/was a major manufactuurer of them. (Plus there was some resentment against the Radio Corporation of America for their tight-fisted use of patents to suppress competing radio makers.) I do not know if RCA ever manufactured their own phono connectors or just used some else's patent ;). Hope this helps. P.S. The original use of the 1/4" stereo headphone jack was an outgrowth of the use of 1/4" monaural headphone jacks on mono hi-fi gear. The use of phono connectors on audio/video gear is likely due to their smaller panel space requirements.
I don’t think anyone else has mentioned it, but a nice thing about modern digital scopes is that you can capture quite of lot of waveform data and then analyze using math software like MATLAB or Octave. Plus it’s way easier to capture images of waveforms of interest for documentation. I humbly suggest people start with an inexpensive digital scope and get good using it. They are small and portable, which is nice. Then graduate to a good analogue scope like the Tek. I use both kinds for all my work. There are some things that my Tek is better at, some thing not.
Wonderful info! Exactly everything I was hoping to find out. I will definitely follow all vids in this course. (BTW: Never seen a RUclips video with zero dislikes before. And this has been up for a year with 33K views as of November 2021.)
Excellent beginning! Really looking forward to your coming videos. Just a few observtions on isolation: Your slide that showed some isolation devices was useful, but there was a something that said a Variac is not an isolation device - something you didn't mention or go into at all but I suspect you'll cover in your next video. Since your coverage is scopes for audio bench work may I suggest you consider expanding on the initial 5 topics currently and perhaps cover areas such as harmonic distortion measurment, inter-modulation distortion measurment, etc. As a side note some of the digital scopes can do BODE plots which are great for frequency response (and phase response) analysis of a DUT. Another related area you might want to consider is spectrum analysis where you'll inject a sine of known purity and see what the DUT does to it on its output - this was a common procedure done with audio amps and preamps when the Hirsch-Houk Labs used to be a regular part of Stereo Review magazine back in the days (I'm dating myself). As you mentioned in the video you're looking at a Keysight model for around $1k for your own use. There are also some from Rigol and GW Instek that can do BODE plots. If I'm not mistaken the Rigol requires an external waveform generator where as the Keysight has one built-in to the scope .. I think. However, in particular the GW Instek 2000E/G series MDO (Mixed Domain Oscilloscopes) have a built-in dual-channel Arbitrary Waveform Generator (0.1 hz to 25 MHz) and with free software from Instek for the 2000E/G scopes can perform a BODE plot. The 2000E/G series MDO scopes also have 1 million point (selectable) FFTs - something you don't find on most other low-end and mid-range digital scopes. And as if that weren't enough, the MDO 2000E/G series have a built-in separate Spectrum Analyzer where span, center point, window type, etc. can be dialed in like a stand-along spectrum analyzer. The "E" version of the series also has a 5000 count Digital Meter (and a 5V/1amp power supply if you're into design). For audio work the MDO 2000E/G scopes are a fantastic combination and you might want to include using one of them (they come in 2-Ch and 4-Ch varieties and span a total of 12 models) in one of your future videos. I should mention I am not connected with GW Instek in any way, but I have been looking for a scope to do more than just the usual and after comparing their scopes to some other brands/options the Instek MDO-2000E//G seem to give you quite a bang for your buck, so I purchased their MDO-2104E (100 MHz, 4-Ch) for my audio work. Looking forward to your next videos!
Thanks Mark - Great to see you up and running with the Scope series - good introduction - Tick box checked . All the best to you and your family over the festive ( be it subdued) season, stay safe .
Thanks for sharing your knowledge with everybody. Guys like you, D-Labs, (I think it's Terry), and Uncle Doug are really appreciated, and I think you guys are pretty rare today. My question to you is, in buying older (vintage) gear such as a scope, do you need to be concerned whether it's in decent calibration? How do you verify, by comparing with a audio generator?
Basically you need a device that is known to be calibrated.. Like a Fluke meter. use that to measure and compare to the voltage reading on the scope. adjust the scope tp read the same voltage as the meter.
Like Kevin said, there are various ways of checking calibration - sort of, but for most audio work, calibration is not that important. What a signal looks like is more important than whether it is 1.8 volts peak to peak or 2.0 volts.
I fell in love with the 2465B when the US Army replaced their aging 485s in the late '80s. I have a 2465B (100% functional), a 2445B (100% functional), another 2445B (about 80% functional), and yet another, possibly repairable 2445B for parts. I *like* TEK scopes. OTOH, even a TEK 2445 is overkill for nearly all home and hobby use.
Love it!!! Thanks so much for putting this series together. Been wanting to go beyond the basic obvious repairs. An oscilloscope is something I've always wondered about, so thanks again for this series and I'm really looking forward to seeing the rest of them.
I settled on the Hantek DSO5072P two channel, 70MHz digital oscilloscope and a Koolertron two channel, 60MHz arbitrary waveform function generator. I still want an analog scope with XY mode so I can experiment with oscilloscope music some time in the future (music that displays fantastic images on an oscilloscope in XY mode). Cheers!
For basic audio work, there's a cheap Chinese unit that Dave over at EEVBLOG did a review on it, he didn't like, probably wasn't up to what he might have used it for but someone else did a great review on it, I think that it was the learn electronics channel, it's got a built in lithium battery and a 7" screen, has FFT and covers the audio frequency range! Because it's not plugged into the mains, it's isolated and being extremely portable you can use it on your car if the need ever comes. The brand is FNIRSI, has two channels and is touch screen! It does have menus but no where near as much as other scopes! You will find that the touch screen works really well to. But the price for what you get just can't be beat! It's battery is charged by usb and it's battery can be upgraded to something much larger if 4 or 5 hours isn't enough! It's actually built very well and feels very professional! It claims that it can measure really high frequencies but it can't, but for 0hz to 50kz, you will be covered, it can go higher but I only use it for audio, displays voltage and other data along the bottom of the screen which you can pick and choose which data you want and both channels data can be independently chosen! It's not as good or featured as a Rigol but it's almost half the price! For getting started in audio, I think that it's perfect! I also have an older CRT scope which doesn't do any data and I even got one of those tiny little all aluminium cased two channel scopes, it's also great just for audio but it's tiny 2.5 or 3" screen isn't something that you want to be starring at every single day! It's great to drop into your shirt pocket and go for a quick once in a blue moon but definitely not every day! So yeah, I think that the FNIRSI is definitely worth it if it's in your price range and you are only working with audio! If this unit becomes popular, I'm sure that the next model will have improved performance and features! I love it ❤️. I got mine from eBay but it should be also available on Amazon to... Check it out!
I was recently gifted a Tektronix 2235 and just finished this first video and wanted to say thank you so much for a easy to understand approach. I actually take notes in a graph composition notebook. I'm 53 and wish I started sooner but I am doing it now. Thanks again.
Better late than never!
Been an audio engineer for 30 years (live sound, touring) and am just now getting into learning about this stuff. I was on it as a pre teen back in the 80's but got more interested in other aspects of the field. Now I've got some old reel to reel machines (Nagra IV-SJ x 2) I'm using to record the band I mix and those need maintenance so, off we go. Tektronicx 465 Purchased and now, thanks to you I'm looking forward to starting this journey of learning to care for my tools. Thank you.
Thank you! I've learned so much from your videos. You make electronics so much clearer for this old knuckle dragging retired Soldier.
Thanks so much for taking the time to do this series. Extremely helpful for the likes of myself who hasn't used a scope in more than 60 years.
Best wishes to you and your family for a healthy, happy, and prosperous new year.
My man. I just love your channel so much. It's packed with such useful, practical and well presented material. I'm fairly confident that you're content has put a lot of bread on the table for mini folks and I hope you're being well supported by them.
Probably the best YT video I've seen on any subject matter. I can't wait for the rest of the series...thank you.
Simply the best presentation on the How, What and Why of an Oscilloscope and accessories for the audio bench. Straightforward, practical and understandable. Mark you're the best! Thanks for sharing your expertise and time. I am getting back into vintage electronics and have discovered your videos as my main source of education. Thank you. Thank you. Thank you!
Mark - looking forward to the rest of the series. This will help reinforce what I already know - really appreciate it !!! Ron
Been in electronics for 50 years and just learned that I can still learn new things. I have the same isolation xfrmr and never thought to plug in a power strip. I am going to do this and paint it red and next to it the other will be it's natural silver. Great tip.
Perfect, it's the last bit i have to aquire to begin the real work on the audio signal. I've been playing too long with swapping parts now it's time to really see what they're doing in the circuit. Thank !
Wow! What an incredible series of videos. Was absolutely critical in helping me trouble shoot my preamp restoration safetly!
Perfect timing... already have much of this equipment, but just learning to use it with audio equipment.
Is your dog part Chihuahua?
Best way to learn electronics is in college. DC, AC, Electronics 101 to 103.
No time for college? Then learn:
Ohms Law, kirchhoff Voltage and Law, Thevenin's Theorem
Albert Malvino "Electronic Principles" is a really good book. Hook up the example circuits in each chapter and test them with your equipment. You will soon be designing your own audio amplifiers using discrete components.
@@JohnDoe-bf1fw Actually, I have a 3 yr College degree in Electronics... but didn't work at the component level for long, and don't recall doing much related to AC, other than motors and such. My dog was a Welsh Corgi.
Just what I was looking for straight forward info on what's needed. Thanks looking forward to the next video.
What a great introduction. Thanks a lot for taking the time to do this.
In ancient times when I worked at Tektronix, I used a 464 analog scope (I think that was the model). I learned to use it very well and loved it. A couple of years ago, I purchased (used) a Tek TDS420A digital scope with CRT display. Someday I might get it figured out. Like you, I grew up on the analog scopes and am struggling to get up to speed on all the menus, functions, etc., that my digital scope had. I just need to live long enough!
I can tell that you have many years of experience and knowledge of electronics as you explain things so well. Even though I use an o'scope and sig gen for radio tinkering, I do use audio frequencies when aligning radios. So, your video is very helpful to anyone contemplating purchase and use of an o'scope and a signal generator. Thank you very much.
I learned SOO much from your videos and I play them over and over again to let it sink in. Thank you very much 😀
Great video Mark!!! It may also be worth mentioning to the audience, that Variacs (Autotransformers) are not isolation transformers. Many people think they can double as such. Also, an isolation transformer, although electrically isolated from the line and neutral, is not necessarily isolated from ground. If you are going to use a 1:1 transformer for ground isolation make sure you check that the line side and load side grounds are not the same point electrically. For some, this can be fixed by a simple removal of a ground strap connection or snipping the ground prong on the line-side plug. I have a Tenma 72-1095 Isolation Transformer with adjustable voltage and it has a common ground. The load side plugs are connected to ground via a ground wire to the chassis. Disconnecting this wire isolates the load side. Just something to think about. Thanks!!!
Love this series. Thank you. Concerning the channel selection buttons on that Rigol, that's why I won't buy a Rigol and will be buying a Hantek DSO2D15 which has individual controls for each channel and an internal arbitrary waveform generator. It will be an addition to my Tek 465 scope and if I ever get around to repairing them, my two HP 1741A scopes.
Thank you for educating me on functions on oscilloscopes
Perfect Part1 Explanation! Looking Forward To The Next Four Episodes!
I have and use the exact same isolation transformer you have, and use a power strip out from there for everything, including the variac and sometimes a DBT. I just got one heck of a deal on a brand new Tektronix TBS1104 Digital Oscilloscope: 100MHz, 4 Channels, 1GS/s sample for a mere $600. They sell for over $1900 on most places like Mouser. Santa was good to me. lol! The 4 channel is great when servicing quad amps and receivers. The old analog BK 2120 20MHz scope serves the purpose quite well and will not be "retired" any time soon and will be used on a 2nd bench. The Lab-Volt 1236 AF/RF generator works quite well for audio too. Awesome videos Brother!
I'll sure be following this series.
I was given 2 scopes some time ago but not even looked at them, don't even know if they work.
Gonna dig them out soon and get my self familiar with them.
Great video for beginners like myself. Tube stuff isn't my bag. This video is very informative and educational. Thanks for sharing your thoughts.😁
Thanx! Exactly what I’ll need when I get around to buying a scope!
Very excited for this series. Been watching your videos for a while now and you are great at explaining what you are showing. Thank you for the time you put into everything you provide us hobbyist with. Happy New Year
Excellent excellent excellent. Very informative and practical. Just was a person trying to learn about electronics needs. Thank you.
Started research on testing amplifiers with o'scopes and found this, awesome video series. Thanks!
Thank you for this amazing video!!! THANK YOU
I will definitely be tuning in to this 5 part series. Thanks in advance for doing these in depth videos.
I haven't finished watching yet but this is GREAT info. Thanks so much for taking the time to put this presentation together!
This is going to be a Good few videos ! Yes please !
Thank you. I watched episode two before one and asked whether analog or digital and was told to watch episode one. Glad I did. Great explanation. I am definitely looking forward to the rest of the series.
The only reason that I pick a digital oscilloscope due to weight and size.
Great video
I can't thank you enough for this video! I can't wait for the rest of them!!!
This is fantastic! Looking forward to the next 4 episodes.
I want to get into amp repair, pedal repair, modding, building, etc. This video seems very helpful, thank you! 👍
Today I found a signal generator and nice HP tube screen Oscilloscope 100MHZ in our local electronics recycling - . the generator has a gear inside broken so that has to be fixed (it can't dial to the comb filter)
I think it's a simple fix.. and the HP fired up perfectly and your 3rd part video got me dialed in an confirmed. I'm SO happy to have found these today. I agree with the bench space thing. and I have a spot on the bench for this... my first non computer based osc. Appears my HP has pretty much all the same features as that Tektronik minus 2 less channels - 100MHZ is overkill for audio so that's all good ! I had to jerry rig an adapter..will order one of those packages from amazon you showed. Looks great for $20. I can see some great use out of the modern digital units.. but I too hate accessing so many menus. I'm more of a tactile operator. I can hunker in to the 'interface'..but would prefer not to.
I already own an several oscilloscopes but I enjoyed the video and plan on following along so I can pick up new info as you progress through the lessons.
One hour videos plus would be great with precise details photos and part numbers is exactly what we need.
Great video and good advice. Be sure to also get 50 ohm BNC terminators for your scope inputs to assure that you'll see correct voltage readings from your signal/function generator.
This is a great start for a series of usage with oscilloscopes. Loving it so far!
Great series. Really informative and motivational! Keep them coming. Fan from Chicago.
Thanks! Excellent overview of connector basics and oscilloscope basic and setup up for scope operation. Much appreciated!
Thank you for your time, knowledge and sharing your valuable experience. Very comprehensive thus far.
Thanks so much for doing this series! Your channel has given me the tools I need to get into building my own tube amp :)
I had to subscribe again ! I learned all the hertz stuff in the Radio Shack books "AC circuits part one and two". Killer books
Perfect Timing. I am looking to purchase an Oscilloscope for various Guitar amplifier and pedal builds. Looking forward to watching the series....Thank you.
Thanks Mark. It is about time some body explains this with practical applications. I learned this 40 years ago with out applications. Education is such a bitch.
When you get your amp class setup, done I am in. Will see youall in the south..
Very glad to see you do this series! TY!
Very good video, sir. I've ended up with several 'scopes ranging from a late 40s lab model through a dual channel Heathkit c.1970 up to a 100 MHz Techtronics. For audio use on my radios I use the Techtronics or another 10 MHz scope (tube equipment) or one of the cheap DSO138 or DSO150 units from eBay/AliExpress/Bangood for solid state equipment (these are roughly $24 - $30). I have used the DSOs fed through a capacitor for some boat anchors. I plan on closely following the remainder of this series. Thanks.
i used a tek 545 for years and it was a great 33mhz scope with interchangable vertical plugins. In the late 80's that was getting dodgy so I replaced that with 35mhz dual trace Hitachi scope, it was functinality similar to the old 545 and easy to use. The 545 is long gone, the Hitachi is still working great.
I 2011 I got a good deal on a Tek 2230 storage scope that is a 100mhz analog scope with a digital overlay and waveform storage. I used a scope like this for years in my real job so i was very familiar with it. I can now display 4 channels on the odd chance i need to do that by using both scopes but that almost never happens. The digital capture comes in handy if your going through parts trying to select something with known risetimes.
The modern digital bench scopes are interesting but you should be able to find a good analog scope for a good price and as a bonus you can probably fix it yousrself, if a new digital scope dies it has to go back to be fixed and will be gone for weeks or months and cost a lot to repair.
As to the ability to display measured values on the screen i find i can do the math in my head faster than what it takes to set up the fancy scopes.
Looking forward to the rest of your series. Started my tech bench about 2 years ago and went through this entire process without as much guidance. The one area that stopped me cold for a bit was the stupid and mislabeled isolation transformers on the market. Very few are actually isolated. I am not referencing a Variac. They almost all tie the ground blade to the round ground plug that you are expecting to isolate from. I had to learn how to modify a new one by changing out the type of plugs on one bank (there is a special type of isolated outlet plugs you can buy) and removing the round pin ground connection that was originally connected. Everyone that checks their isolation on almost all of these newer ones will be surprised to find they have continuity to the any other wall outlet ground pin. They apparently can call it isolated still because it uses a transformer. It doesn’t have anything to do with ground isolation anymore. Your older isolation model or use of 2 prong adapters is the easiest method to go by.
Agreed. Isolation transformers are sold with safety in mind. The problem, as you stated, is that many iso transformers are not true isolation transformers. You *cannot* blindly trust your life - or test equipment - to an iso transformer. There are a lot of gotcha's involved. You *must* test the thing. Corollary - You must know how to test it.
Great start to an exciting series
Great intro series for new learners and old dogs too. Those old 10 to 20 Mhz scope will serve one well, I saw 100 Mhz scopes for as little as $50 dollars a afew days ago on the web.
This is a very helpful video series, I was searching for something like this long time up to now, I respect your work and your time to make this educational video. Thank you!
Really good,very interesting ,thankyou
Awesome Part 1. Can’t wait for the rest of them!
Thanks so much for this series !!!
Great video. Straight to the point and easy
Class !!! but a good multimeter is need too .... a precise of coarse !!!
Happy good year Eric from France
And it pays to get a good quality meter. Although the "cheapos" do work, they don't work very well after a while and will become intermittent from oxidation on all the contact areas. Areas like the switch contacts and probe sockets where you have to "wiggle" them to regain non-resistance contact. I finally went with Fluke when I could afford them and never looked back. There are other "top shelf" brands as well. I still use my "cheapo" meters a lot for things like "quick" checks and the like to save wear and tear on the Fluke meters.
Very practical information. Thanks!
excellent tutorial and clearly explained for starters
Best of the Holiday wishes to you and yours! Very excited that the O-scope series has started (especially looking forward to the safety part).
Thank you!
A thing to keep in mind when purchasing a scope, is how deep is your bench?
The older ‘tube’ based scopes, are considerably deeper to accommodate the tube compared to the likes of the newer digital scopes like the Rigol which are the opposite!
I agree whole heartedly. Sadly, because I'm so "old school", I love my Tektronix 2246. I know every button and knob, and like having discrete controls. I do have a Siglent 1104x-e, but haven't come close to mastering it's capabilities nor it's menu system. I also have an HP-54610b with it's memory module, which is an awesome piece of gear.
Since I'm a tube roller guess I'll comment. First of all love your channel thanks for all the info. I just won't work on the amp when it's plugged in. I power the amp down, move my connection, then power it back up. Takes longer but it's a safety step I won't skip often. Also people with isolation transformers need to know they can't use test instruments that way and they are grounded if nearby. Which means also you could touch the ground on the oscilloscope lead when you hook it up to your amp. It takes very little current supposedly to kill a person. Having the amp turned off when moving your connection isn't ever mentioned. The 1 hand rule is impractical. You eventually will inadvertantly have 2 hands in your amp. You can see powering the amp down doesn't take that long. If Working on it powered up MUST wear insulating gloves such as latex, and only one hand if possible.
This is just great! Thanks, Blueglow Electronics.
An extra thank you for not saying "one Hurt, two Hertz" :D Most Americans I've heard on RUclips confuse things that way.
I admit, I'm American and just reading comments in most of my subscribed channels is usually frustrating, and honestly embarrassing! As you've probably figured out, our education system is surely lacking, and it must really make Europeans and Asians cringe! I love my country, but we fall way behind in education. ✌😵
great video I have been thinking about starting to learn how to fix my vintage gear for awhile now . Thanks for the info to make my mind up and start gathering the things I need Great video and thank you very much
Very helpful and useful information. Thank you!
OUTSTANDING video! I appreciate all your effort to put this together!
You are awesome. Thank you.
Great timing. Just purchased a Tektronix 465.
That family of scopes has a well documented history of problems with the vertical attenuators and a bit of a PITA to work on.
OTOH, it is also well known to be a genuine workhorse
Wow bud.. really appreciate you making these.. thumbs up for sure..
Can't thank you enough for this video and the accompanying series! Saved me tons already, as I am just starting out with this hobby! SUBSCRIBED!
Thank you for a great video 😊
Great video. I picked up a BK 1474 for $50 Canadian!
I own a Yamaha CS30 synth and have been looking for advice on oscilloscope buying just to check waveforms etc. pleased to find this.
Great series! Thank you for your hard work!!!!
I can add a little info on vintage scopes as I have just done some research and testing for model railroaders who might want an oscilloscope for measuring the "Digital Command Control" voltage but don't want to spend much. (Plus, I have used such scopes in my mercilessly long career.) One thing to remember is that the major manufacturers each had a range, often a very wide range, of oscilloscope models and usually the bottom of the line would be fine for audio. But on the used market, there tends to be far less of a price spread between models and manufacturers than for the original price spread. The Tektronix 465 mentioned (or you might be more likely to find the 465B) was a top line oscilloscope (the industry standard, actually) introduced in 1972 for $1,725 ($11,470 in 2021 dollars) sells on eBay for $100 to $250. A Tektronix 2215 introduced in 1982 for $1.400 ($4,032 in 2021 dollars) sells used for $50 to $150. A Hitachi V-212 introduced in 1983 for $340 ($949 in 2021 dollars) sells used for $50 to $120. Of course, offerings vary in condition a lot, but you can get a very nice vintage scope for so little money that the biggest concern might be the shipping cost and perhaps having to buy some probes. If buying a new digital scope, typical names today for bench scopes are Siglent, Rigol, Hantek, and some others. (I recently got a Siglent SDS1202X-E and think it is rather decent.) RUclips reviews abound on new scopes but beware that some reviews are by some who are not very knowledgeable and some by those with decades of electronics training and experience. While the lowest bandwidth models are adequate for audio, it often doesn't cost very much more to get much more bandwidth and perhaps more features. Frankly, the options today for low cost oscilloscopes made in China can make you feel like a kid in candy store. Some scopes I would NOT recommend are the "mini" DSO's or "Tablet" oscilloscopes. While usable, most wildly exaggerate their bandwidth and can be annoying to use with minimal controls and maximum menus so you are forever cursoring, cursoring, and cursing to make changes. Also, even the lowest end mini-DSO (200 kHz claimed bandwidth, but not really) is about $75 and if you step up to a better model and you are above $100 pretty easily. They just aren't a good value in my view. They are the sort of thing that, if want to use it regularly, you live to regret. They do have the advantage of being battery operated, however, which certainly takes care of isolation issues.
Greetings:
FYI: As far as I am concerned, all RCA type connectors are to be called "phono" types. They all are single signal (plus shield). They have been around a long time and were originally used to connect the first phonographs with electrical pick-ups to tube radios equipped with a single RCA connector to use the radio's amplifier and speaker to listen to 78 rpm records that had once been played on wind-up gramophones.
All tip-ring-sleeve audio connectors owe their heritage to the original plugs used on telephone switchboards, hence "phone" connectors. Although those first phone plugs (and jacks) were three connector types, the audio industry standardized on them for patching including use for balanced signals.
My first exposure to tiny plugs/jacks were as earphone jacks on transistor radios. Some were smaller than the common 3.5 mm plugs used today. But all are deserving to be called "phone" plugs.
BTW: in Europe RCA phono plugs are often referred to as CINCH plugs as CINCH JONES is/was a major manufactuurer of them. (Plus there was some resentment against the Radio Corporation of America for their tight-fisted use of patents to suppress competing radio makers.) I do not know if RCA ever manufactured their own phono connectors or just used some else's patent ;).
Hope this helps.
P.S. The original use of the 1/4" stereo headphone jack was an outgrowth of the use of 1/4" monaural headphone jacks on mono hi-fi gear. The use of phono connectors on audio/video gear is likely due to their smaller panel space requirements.
I don’t think anyone else has mentioned it, but a nice thing about modern digital scopes is that you can capture quite of lot of waveform data and then analyze using math software like MATLAB or Octave. Plus it’s way easier to capture images of waveforms of interest for documentation.
I humbly suggest people start with an inexpensive digital scope and get good using it. They are small and portable, which is nice. Then graduate to a good analogue scope like the Tek. I use both kinds for all my work. There are some things that my Tek is better at, some thing not.
Hi, many thanks for info, looking forward to next video.
Wonderful info! Exactly everything I was hoping to find out. I will definitely follow all vids in this course. (BTW: Never seen a RUclips video with zero dislikes before. And this has been up for a year with 33K views as of November 2021.)
Thanks, great video… helpful for a newbie.
Excellent beginning! Really looking forward to your coming videos. Just a few observtions on isolation: Your slide that showed some isolation devices was useful, but there was a something that said a Variac is not an isolation device - something you didn't mention or go into at all but I suspect you'll cover in your next video. Since your coverage is scopes for audio bench work may I suggest you consider expanding on the initial 5 topics currently and perhaps cover areas such as harmonic distortion measurment, inter-modulation distortion measurment, etc. As a side note some of the digital scopes can do BODE plots which are great for frequency response (and phase response) analysis of a DUT. Another related area you might want to consider is spectrum analysis where you'll inject a sine of known purity and see what the DUT does to it on its output - this was a common procedure done with audio amps and preamps when the Hirsch-Houk Labs used to be a regular part of Stereo Review magazine back in the days (I'm dating myself). As you mentioned in the video you're looking at a Keysight model for around $1k for your own use. There are also some from Rigol and GW Instek that can do BODE plots. If I'm not mistaken the Rigol requires an external waveform generator where as the Keysight has one built-in to the scope .. I think. However, in particular the GW Instek 2000E/G series MDO (Mixed Domain Oscilloscopes) have a built-in dual-channel Arbitrary Waveform Generator (0.1 hz to 25 MHz) and with free software from Instek for the 2000E/G scopes can perform a BODE plot. The 2000E/G series MDO scopes also have 1 million point (selectable) FFTs - something you don't find on most other low-end and mid-range digital scopes. And as if that weren't enough, the MDO 2000E/G series have a built-in separate Spectrum Analyzer where span, center point, window type, etc. can be dialed in like a stand-along spectrum analyzer. The "E" version of the series also has a 5000 count Digital Meter (and a 5V/1amp power supply if you're into design). For audio work the MDO 2000E/G scopes are a fantastic combination and you might want to include using one of them (they come in 2-Ch and 4-Ch varieties and span a total of 12 models) in one of your future videos. I should mention I am not connected with GW Instek in any way, but I have been looking for a scope to do more than just the usual and after comparing their scopes to some other brands/options the Instek MDO-2000E//G seem to give you quite a bang for your buck, so I purchased their MDO-2104E (100 MHz, 4-Ch) for my audio work. Looking forward to your next videos!
Another great video, thanks so much.
Thanks Mark - Great to see you up and running with the Scope series - good introduction - Tick box checked .
All the best to you and your family over the festive ( be it subdued) season, stay safe .
Thanks Mark!
Thanks for sharing your knowledge with everybody. Guys like you, D-Labs, (I think it's Terry), and Uncle Doug are really appreciated, and I think you guys are pretty rare today. My question to you is, in buying older (vintage) gear such as a scope, do you need to be concerned whether it's in decent calibration? How do you verify, by comparing with a audio generator?
Basically you need a device that is known to be calibrated.. Like a Fluke meter. use that to measure and compare to the voltage reading on the scope. adjust the scope tp read the same voltage as the meter.
Like Kevin said, there are various ways of checking calibration - sort of, but for most audio work, calibration is not that important. What a signal looks like is more important than whether it is 1.8 volts peak to peak or 2.0 volts.
Thank you. Just what I needed
I've got the Tektronix 2245A oscilloscope, which is very similar to your 2246. It's a great scope for a lot of electronics work!
I fell in love with the 2465B when the US Army replaced their aging 485s in the late '80s. I have a 2465B (100% functional), a 2445B (100% functional), another 2445B (about 80% functional), and yet another, possibly repairable 2445B for parts. I *like* TEK scopes.
OTOH, even a TEK 2445 is overkill for nearly all home and hobby use.
thanks a lot for this serie of videos
Love it!!! Thanks so much for putting this series together. Been wanting to go beyond the basic obvious repairs. An oscilloscope is something I've always wondered about, so thanks again for this series and I'm really looking forward to seeing the rest of them.
Thank you, thank you, thank you!
Happy New Year!
Tom
I settled on the Hantek DSO5072P two channel, 70MHz digital oscilloscope and a Koolertron two channel, 60MHz arbitrary waveform function generator. I still want an analog scope with XY mode so I can experiment with oscilloscope music some time in the future (music that displays fantastic images on an oscilloscope in XY mode). Cheers!
Brilliant Work...!
This will be great. I'm one of those guys who has a scope but only use (maybe) 10% of it's functionality.
Excellent video, thank you.
For basic audio work, there's a cheap Chinese unit that Dave over at EEVBLOG did a review on it, he didn't like, probably wasn't up to what he might have used it for but someone else did a great review on it, I think that it was the learn electronics channel, it's got a built in lithium battery and a 7" screen, has FFT and covers the audio frequency range! Because it's not plugged into the mains, it's isolated and being extremely portable you can use it on your car if the need ever comes. The brand is FNIRSI, has two channels and is touch screen! It does have menus but no where near as much as other scopes! You will find that the touch screen works really well to. But the price for what you get just can't be beat! It's battery is charged by usb and it's battery can be upgraded to something much larger if 4 or 5 hours isn't enough! It's actually built very well and feels very professional! It claims that it can measure really high frequencies but it can't, but for 0hz to 50kz, you will be covered, it can go higher but I only use it for audio, displays voltage and other data along the bottom of the screen which you can pick and choose which data you want and both channels data can be independently chosen!
It's not as good or featured as a Rigol but it's almost half the price!
For getting started in audio, I think that it's perfect! I also have an older CRT scope which doesn't do any data and I even got one of those tiny little all aluminium cased two channel scopes, it's also great just for audio but it's tiny 2.5 or 3" screen isn't something that you want to be starring at every single day! It's great to drop into your shirt pocket and go for a quick once in a blue moon but definitely not every day!
So yeah, I think that the FNIRSI is definitely worth it if it's in your price range and you are only working with audio! If this unit becomes popular, I'm sure that the next model will have improved performance and features!
I love it ❤️. I got mine from eBay but it should be also available on Amazon to... Check it out!