Thanks for the video. I think I might still have one or 2 of those that are similar in my classroom storage. I never knew what they were for since I have several 60-70 vintage scopes that have the dual trace on them. I likely have one or 2 that have a single trace that I can use it on if I decide to restore it. My department wants me to throw them and buy new scopes and I do have 2 new DSOs but I still like the old units as they are simpler for students to use at first to gain an understanding of function before letting them play with the fancy DSO that does everything for them and has enough buttons to make their eyes gloss over. I need to go through all the working scopes and replace caps before they fail. I did replace a few bad caps already on 2 that were not working and they sprang back to life.
Those older scopes are your best learning tools, don't discard them, use them to teach! The newer scopes are fine for the end result (solving a service/repair issue) but very poor for the understanding of the scope itself. Sounds like you're on the right track kuhrd!
I was looking at the TBS1000B-EDU line of scopes if I do have to buy a few replacements in the future but I will try and keep the old stuff going strong for as long as I can. I have 2x Rigol DS1054Z that I have not firmware unlocked yet (waiting for the warranty to run out) I snuck them on my new class budget when I resurrected the electronics class 2 years ago. Electronics had not been taught since I was in high school at the very same school. Kinda felt it was my duty to get the class going again. The Rigol DSO scopes work well enough for showing students waveforms and troubleshooting circuits but I always let them play on the old ones first. It is nice to have access to a scope with 4 inputs when doing things with Arduino and stepper motors. Some days it is hard enough convincing the trouble makers that the lab power supplies are not arc welders. On those days when I am working on my own stuff I wish I had even 25% the experience you have with electronics.
Very much enjoyed watching your channel for the first time. Seeing that Heathkit oscilloscope brought back great old memories. Around 58 years ago I was a teenager working the summer as a dogsbody in my father's marine electronics shop on Fort Myers Beach, FL. It happened that he needed an additional oscilloscope on the work bench for the technicians. So he purchased a Heathkit and put me to assembling the unit. Well, I was over then moon being given such a challenge and responsibility. I completed the assemble and when the time came, it didn't work. One of the technicians took to troubleshooting the unit and found that I had failed to put a ground insulator between one of the can capacitors and the frame. Easy fix and I was relieved.
Hello a general question related to use and restoration of older test gear in your projects have you worked on Fluke 8600A DMM's? I have one I am interested in getting back into working condition. TX Theo
Thank you for showing this. I have a project that i wanted to get started on and you gave me the motivation to work on it. One thing i need to get is a tube tester. for the past 2 years I have been obtaining tube radios from clean outs, most are in bad condition. I save the parts from them to one day build something crazy. I was thinking of a 7.1 surround system. something that i can be proud of. I had a teacher long ago that took his time to show me how tubes worked. Build my first radio for high school. Thank you again for taking your time to show us the projects you work on!
Hell,Paul! My name is Jim Ashton and I was born in Birmingham in England in 1943, so you can understand that this video took me back in time to my early days in valve (tube) electronics.I was most impressed by your very clear explanation of an instrument which I had never encountered. At no point did I become bored and I picked up a lot of useful tips. I shall be following your videos avidly from now on. As a matter of interest (or not!) I am now a qualified Egyptologist and travel each winter to that country. There is no danger and I encourage all my friends to go there and see the miracles that these people wrought! Jim.
Great vid! My dad was an electronics tech for 60 years, graduating from Oaklands' Central Trade School, in 1937. Seeing these old units brings back countless memories. :-) It's great, knowing that there are young people keeping the old trade alive.
Thank you Mr Carlson! I am a motor head/electronic hobbyist from way back who has always had a fascination for old tubed devices. I understand enough about them to stay alive while servicing them but have had a few things puzzle me about their operation, one being “bias”. Your comparison of bias being like a stall converter on a starting line is one I understand well. Now I understand some of the mechanics behind bias as well! My shop is almost finished and I hope to put all the old collected equipment back to work here soon. Thank you for the awesome video's.
I'd have to say this instructional on older tube technology is probably the best I've found on RU-vid. Thanks for providing your knowledge and time to educate the rest of us. It's appreciated very much.
Big thumbs up for Mr Carl son's lab. I must get my patreon account sorted out. I just love the calm and logical but warm and engaging delivery. Thanks again.
As a retired EE, born in 1941, I can attest to the knowledge of Mr. Carlson. Other than a very minor pronunciation error (silent "l" in "solder,") this is a perfect video. Excellent in every respect.
I apologize, Paul, for the misunderstanding... I have since seen the outrageous lengths which you take to remain completely purist in every respect in all of your videos. In fact, I have to watch out that I don't start talking like a Brit and make people think I'm a transplant to the US! LOL You have set an extremely high bar for the rest of the electronics community. Bravo! de KQ2E
Always amazed at the knowledge on tap, in your brain. I have experimented a little with small projects in the past. But, I could never retain your level of knowledge. Fascinating to watch. You have convinced me to get another soldering station and get back into it. I'm retired now, so I have the time. Just not a lot of money or brain capacity to do much. But, I really enjoyed it, back in the day.
This is awesome. As soon as the cover came off, the quality was evident. I sold my dad's O-11 scope before I saw your restoration video, and I hope the buyer enjoyed restoring it - his intention. He may have seen your video. Very enjoyable watching your restoration and explanation. Excellent work!
My first job in 1982 was working with an older gentleman in a two way radio repair shop. He had a lot of equipment like this. Sorry to say it all went to the dump. Glad to see you save some of that kind of stuff.
Excellent information, great detail. Many of us old timers learned about circuit design (and mechanical design) by disassembling military surplus items. Helps to develop a way of thinking that is invaluable today.
You find the neatest stuff! I especially liked the sleuth like detective work into the suspected low hours of use. Thanks for taking the time to draw up and explain the schematic.. I always learn something from your video's.. A++
Omg this channel is so useful but i could never watch it until i found 1.25 play speed. Now i can remember the beginning of the sentence by the time he reached the end of the sentence. Before i was falling off the concentration. Now it awesome.
my first oscilloscope was a sencore PS148 from the early 60's. I'm in the middle of restoring a vintage general radio audio frequency generator. love your vids!
What a reminder of my old years as a Radio & TV engineer !!! I loved those Continental Transmitters with a built quality as that Sylvania switch. Keep posting videos !! :)
This was very inspiring. Admiring your deep understanding of this technology and the way you bring it out to us. Thanx for bringing the zeitgeist of this era back to life.
I've been loving your videos Mr Carlson, they're all very informative, educational and very interesting. This was a great device, excellent restoration and great to see this old equipment come to life.
@@MrCarlsonsLab very much so, to the point where is renewed my interest in vintage tech. I recently received a General Radio Company impedance bridge. Note I just need to understand how it works and restore. Your videos are awesome, I'll be a patreon as soon as lockdown is over in my neighborhood.
I actually have a radio built in 1944 that still works. Hand wired, original valves (tubes). I tested everything before I applied power. The set was bought by my grandparents, and still has the shop guarantee. They were supplied as kits of parts to local shops to assemble.
Steven Cook, Make sure you replace the caps as does Paul Carlson. That will keep your machine working for decades more. Add to the voltage rating as they are not the same as the caps were back then. Use a good brand (see his video on choosing components by brand).
This is great. Had no idea what it is was for, until last part of video. But glad I stayed till end, as I just built an oscilloscope from a very old book written in 1979 by a chap named F.G Rayer. (one of the many brilliant Babani project books) Really simple circuit and covers 20hz to 20khz nicely. But of course its a single channel scope. So now you have shown me how I can turn it into a two channel scope. Brilliant!!!
On the EICO 488 Electronic Switch they labeled that "Balance" knob as Positioning, and there's a Heathkit model that calls it Separation (A up and B up)... So EICO and Heathkit agree with Mr. Carlson :)
Great Video! A lot of good advice on how to approach a restore. A valuable take away for me was drawing the schematic, reverse engineering, since nothing was available. I am restoring a Hickok 209B VTVM, unlike other models in the series , no documentation appears to be available. I am going to stop searching and start drawing, a bit of work, but part of the restoration journey. Thank You!
Marvellous stuff... I grew up in the days of valves (sorry, tubes 😎 ) when things were simple, or seemed so to me. That certainly brought back memories
When you switched on the switch box after it was connected to the oscilloscope and we could see the path of how the two lines are made @ 1:07:03, that was really neat. Thanks for sharing this all. I wonder how hard it would be to make an equivalent of this for that cheap single channel scope I have. oh and then you really show how it works later!
Excellent restoration and presentation. I was surprised how good the channel switching square wave was with reasonably fast rise time and virtually no overshoot. Would like to have seen a DC offset control to allow DC measurement on both channels. Thank you
Another great restoration video! About the Leaf...Historically, the oak leaf is a symbol of endurance and strength. It might be a marketing stance by Sylvania as a "Mark of Excellence".
Mr. C I have really enjoyed your videos. If I would have had teachers like you I know I would have been a better student. So thank you for your efforts. I look forward to every video and am learning a lot on your patreon site as well.
Cool find! I have GOT to go to ham swap meets! Not only is that well constructed as you say, but in promo condition, as if it was shipped to you from 1939! Thank you for sharing it with us! You rock!!
Excellent video. I am from the UK, sadly no one in the UK produces Video's like you, Keith Rucker, etc. do from over the pond! I was an apprentice 1953/1959 at the D.S.I.R. Radio Research Station working for Dr Smith Rose, Wilkins, etc. making the all the type of equipment you are interested in! Your video,s are jogging my memories ,
oh boy, it is quite a process to draw up the schematic from the equipment. Trust me, you will go through several iterations, before you draw together all the information, and the circuit makes enough sense, that you can then draw it conventionally.. you start with what is essentially a pictorial and work towards a schematic. Nice result Paul.
Very enjoyable video of a great old piece of gear. I was amazed how well that switch worked. I'd love to know how much usable bandwidth that switch has. It goes to show there were some very capable engineers back in the thirties when electronics was in it's infancy.
I have to confess, I got a chuckle when your schematic popped up. I'd made a prediction about the 6J7 tubes, after looking them up (RCA made them too, and sure enough they were in my copy of their receiving tube manual RC16 from 1946). I figured they were being used as amplifiers for the inputs, with the gain controls connected like simple volume controls. That's neat how they're connected to the oscillator, though :D
Your videos are not only stimulating for the brain, but they're a treat on the eyes too. That thing is ridiculously gorgeous. It really reminds me of the old equalisers they have in the Abbey Road studios.
One thing I would like to say Paul, is that although the old equipment can be harder to use, if there is a failure for any reason unlike modern ic/ transistor gear it usually won’t cascade taking out lots more components. IMO
I had an electronic switch by Heathkit. It really is very limited since two different signals of different frequencies could only be set for one of them. Good for comparing the input and output of an amplifier. It's a good thing they came out with dual trace scopes using two electron beams which are independent of each other.
very cool! I've got a very simular setup with a dumont 185A and an older heath kit scope. unfortunately they both need restoration... thanks for the great walkthrough on your process. I hope one day soon to have the time and money to replace all the caps and faulty components.
Gee Whiz Mr C, I HAD one of these!!! Earlier type - didnt use a 7N7 - all octal, save for a type 80 4-pin rectifier, and the chassis was a ways longer (the whole thing was bigger) but the same animal, same dials, and called itself an electronic switch! Sadly I LOST my heavy metal boatanchors in a massive London (illegal) Eviction, but wow - nice to see ! Cant remember now whether I traced the schem out, or there may have have been one stuck to the casing...
I like your channel a lot for the older technology. Very few properly appreciate the past technology and its value. Old technology may be less functional though it well makes up for it in it's inherent beauty. For example, LCD displays and LED displays may be safe and lower current but they both pale in comparison to nixes or vacuum fluorescent tubes in looks and contrast.
Isn't it strange how some of us can find that piece of electronic wonderment a thing of beauty, how we'd rather have that than some artistic piece of glass or sculpture. How even Mr. Carlsons schematic has a beauty all it's own. Thank you for this hour long wonderful video, had me transfixed when the rest of the family are watching the rubbish they transmit these days. Condescending maybe, but I think I was in a much better place. A new sub.
That power cord you cut had obviously been replaced previously, probably in the 1980s judging from the neoprene cord and the (probably added) hold-down clamp that is using a Japanese Philips screw. It is very possible that the fuse block was added at the same time, the original either not having a fuse or having a fused plug. That tells me that someone either restored this once before in the 1980s, or possibly was even using (or attempting to use) it at that late date.
One little thing,you can sometimes get a schematic pretty close by reading some of the old Radio Amateur's Handbooks(ARRL).A lot of the circuits are quite close.
I have a story I spent 7 years in the NAVY on submarines during the early 80 s I would have done but got hurt on board leaving me crippled for life. But 1 thing we had was a MK 19 gyro that was made in the same time as the subs in the early 60s . I was on SSBN 619 634 and they go out for 70 days or so. The mk 19 gyro is one of the ways to stere the sub. I had to got to school for 3 weeks just to learn everything about it It has 307 tubes and we carried a tube tester and 2 set of tubes.If you could not figure out how to repair it you had to retube thing. Every tube is tested at the factory 5 times and run in a circuit . As you pull the tube you test them but you were not allowed to stop and just replace it you had to keep going .But you did write on the tube it was bad as if you use both sets of tubes you can try replacing what you think is a bad tube . We had some pretty nice troubleshooting knowledge after that school and after you worked on the real thing on the sub. When I got out disabled the NAVY told me they had over 1/2 a million worth of training in me But man those were the days as there are only about 150 guys on board and you know them real well.
Thanks for sharing. Cool device! I might add that an analog Ohm meter is ideal for testing potentiometers. You can go through the full range and watch the needle more slowly (or not smoothly). Especially useful for carbon pots rather than wire-wound, but still the best tool for the job. DMMs are not great for pot testing.
I remember a similar electronic switch made in the late 50's or early 60's. I think it was made by Heathkit or Eico. We had one in the lab at school. Pretty cool device for the 1930's.
Thank you for your excellent presentation. Not being an electrical engineer and having only limited understanding of circuits, you make it very easy to follow along. In your circuit schematic you have the range switch in the order .01, .05, .001, .002pF. Are the first and second position out of order as it increases in value then decrease at the third position and fourth position?
One thing about serial numbers. Manufacturers routinely reserve lower ranges of serial numbers for prototypes and preproduction proof units. Your unit might have a really low production unit...
Can't wait to see you spending more time in the second "old time" workshop. I honestly believe the equipment made back then with valve/tube analogue technology is so much better than todays digital technology. I just feel a bunch of 0's and 1's can't replace an infinitely variable signal of analogue. Miniaturisation aside, I don't think anything made solid state is quite as good as a good quality tube appliance. Trouble with Graphite is it creates a reflective surface so light reflects off it where as black ink tends to be more of a matt finish. That's why camera's and photocopiers tend to hate graphite drawings.
I’m gonna try to repair/restore my two scopes. A Sencore PS-148a and a Heathkit IO-4541 they’re both out of wack and the Sencore was making some banging noises (which were probably the electrolytics(?)). Eventually I’ll use them for test equipment and displaying music as traces and XY vectors, I’m going to try to build a dual trace adapter so I can display both channels on the 4541.
Heathkit had the ID22, but this Sylvania is much btter. I liked how the cans are placed away from tube heat. Lookin forward to the new "mad scientist laboratory" Paul. First project... Jacob's ladder and Tesla coil, lol. Don
