as-salamu alaykum friends! As usual YT is evaporating all the comments regarding the first few opening sentences of this video. I welcome the open discussion on any topic but they just won't allow it.... shalom
I live how Waters, and Talib can literally try to incite riots, but then they say Trump did that. Call him a warmonger, but monger wars. I hope the draft that is coming includes all bipedal entities, or the draft dodgers will all identify as women.
1:04:02 There is nothing wrong with your television set. Do not attempt to adjust the picture. Shango066 is controlling transmission. He will control the horizontal. He will control the vertical. He can change the focus to a soft blur, or sharpen it to crystal clarity. For the next hour, sit quietly and Shango066 will control all that you see and hear. You are about to participate in a great adventure. You are about to experience the awe and mystery which reaches from the inner mind to...The Outer Oscilloscope Restoration Limits!
As a young-un in the 60's, I considered whether or not they really could control my television set. I concluded that indeed they did, because they sent signals which caused my TV screen to behave as it did. However I did have ultimate control because I could change the channel🤓
@@cmans79tr7 In the '90's I precisely experienced that: I had a TV for 3 years, 2 weeks over warranty. I did what I never did before, I had to see a certain program so bad, that I put a note under the picture for a week so I was absolutely sure I did not mis it. At moment supreme I installed myself in front of the TV with drinks, food, and expectations for the 30 minutes experience. Camera's roled, promo's ended, and there the first introduction of the program..... disappeared in a flash of silence. The TV was out, nothing to see or hear but sweat and confusion. After 15 minutes I took out a screwdriver and DMM, opened the back of the TV, and started wondering where to begin. Ah, I see a fuse.... Open !... 2 Amp fast. Went and found a 3Amp slow, put it in, and the TV came to life, many minutes after the program ended. I was had. That TV lasted for at least 7 years, 6 hours a day, with that same fuse, it never popped again. From that day on I was (am) sure that some TV's are controlled from the outside, probably through mains modulation or maybe on the carrier. It had chips in the PSU, so possible in my book.
Thank you so much for taking the time to make this video, especially in light of the YT thought police. I have gotten into vintage electronics and have learned so much from watching your channel. Your efforts are NOT being wasted, not by a long shot.
Hello from Poland 🇵🇱 Shango, I train Ukrainian medics in battlefield emergency casualty medicine and evacuation. I have been watching your videos for 8 plus years, I use them to relax and forgetabout the war to the east. Thank you again brother
@@shango066 that is so cool brother, happy Halloween, here we call it all saints day, everyone goes to all graveyards and we clean all Graves put flowers and candles on them and the space station took a picture of Poland during that night showing all graveyards across the country shining briter then any of the cities. Love your videos Shango, thank you very much.
Watching this while building a 2GHz PLL synthesizer from microscopic smd components. The difference in technology is unreal, what a difference 50 years of advancement can make. Thats why your videos are soo interesting, showing the crude and crusty beginnings of electronics.
Smd is super good, but you are afraid to sneeze near such small spare parts, and when they fall on the carpet, they and that moment are remembered for a long time
I revived an old 60's Eico.. just for the coolness aspect. I also picked up a Hickok scope a few years ago. Woah, what a difference in build quality. Its like comparing an old American car to a newer German import. Exceedingly over engineered..double or triple the weight, double the tube count and also 3 neon bulbs inside. I'm guessing for voltage regulation in a few circuits. Still trying to get that Hickok going. HV issue and have replaced everyrhing already....CRT is ok, works in the EICO.. it's now a rainy day project.. Thanks for the slightly different content. It helped my theory of operation on these.
You can always build Mr. Carlson's curve tracer and use it with that. Really cool project anyway. I think it's worth restoration. Thanks for doing a video on it.
Er, Just had to say, its not Mr Carlsons curve tracer- Curve tracers have been around since well before Mr Carlson. He would tell you that too, it is a standard piece of equipment. Not having a go at either you or Mr Carlson , who is amazing, (and I'm sure you are too 🤠) just wanting things correct.
Shango, I have watched your video's for years. LOVE THEM ALL! I have learned so much just watching, you are inspiring and a great teacher! I also love your comments and your funny words you come up with. A while back, I purchased a Cobra 2000, yea a CB and of course I got the mouths on Ham Radio throwing out attitude. Its Radio for gosh sake! Due watching your video's I was able to just look at the radio and know what was wrong with it before I bought it. Made a deal with the owner and brought it home. Stuck it on the bench and repaired the PLL by replacing the chip. I wanted to go through it and replace WHAT needed replacing only. By no means would I consider myself great at electronics but since watching your video's I have more successes than failures. The Cobra only needed just a few parts replaced to bring it back totally and I have been offered a small wad of dough for it. Not for sale, by the way some of the mouths were trying to buy it. Not a chance after their snide comments. I believe in Radio we all have a common interest and should work together and stick together and lay back the differences. We all love our radios so yea a start right. I have been a Ham since the 80's and played with CBs in the late 60's so I love radios, does not matter one bit to me what kind of radio either! AM Broadcast, shortwaves, CB's, Ham Rigs. Hey if it is Radio I love it! Back to the point YOU ARE MY FAVORITE TH-camR AND I WATCH EVERY VIDEO YOU MAKE! ALWAYS LEARN SOMETHING! ALWAYS! If you are ever in my area, Blue RIdge Mountains, look me up, you have a place to visit and hang out Anytime! Love you Dude you are great!
If the 60Hz sine wave signal on the vertical and horizontal is the same, it will produce a line. If they are 90 degrees out of phase, it will produce a circle. I used to do a lot of experiments with picture tubes and CRTs. When I first started experimenting, I hoped two sine waves in phase would produce a circle!
You out did your self today. I laughed the whole time you were deep frying the caps. I was waiting for you to drop some corn dogs in. Always a hoot... Thanks.
Learned a lot over the years from your videos. Fixed quite a few of all American 5 tube radios thanks to your knowledge. Keep up the great educational videos my friend!
I'm sure Shango was just playing about, the problem is not just moisture but the paper has undergone an irreversible change and has lost most all of the properties it had. It is now just some variable stuff of unknown quality holding the bits apart. What is known is it will break down at a much lower voltage, and does. As usual Shango does the unusual and fascinating things. I love it too, but here its pretty pointless to expect lasting results.
Thanks for your efforts on the behalf of us who enjoy this old equipment and the memories of using it to diagnose and repair old technology. The "Let the good times roll" at the end broke me Way to go Shango! Todah rabbah.
Horizontal and vertical tied together will give you a diagonal line. You need to make one of the two 90 degrees in reference to the other with a cap and/or coil. Great video as always.
@kti5682 Oh yeah, duh. I forgot about scopes having blanking circuits. It's been a while since I've repaired one. I know next to next to nothing about tube based o-scopes.
@kti5682 Could be something to do with circuit design. I wonder how an old tube Tektronix scope compares. Maybe they have a blanking circuit and these cheaper "off-brand" scopes didn't (= costs more).
@kti5682 The retrace time of this scope is fixed but the main travel speed is not. On the slower settings where the retrace time is a smaller percent I think the retrace line is noticeably less visible.
That capacitor shorting at the end is a good example of why I replace ALL electros when restoring old tube equipment whether they test good or not - especially on gear that a customer is paying to have restored / repaired. I don't want them calling me a few hours or days later saying it's not working or something isn't right. Yes it takes a bit more time to cut them all out and replace, but it's worth it in the end.
Check back next week as Shango adds storage, delayed-sweep, FFT and increases the bandwidth to 500MHz! Actually (as the lore goes) you are supposed to only increase the wax just above boiling-point of water; then leave them in for several hours so that the water egresses, and the wax then ingresses to displace any voids and seal the capacitor from further moisture entering. This was a common farm/depression-era practice, and did work for capacitors that were not real old, whereby internal corrosion is actually more of the problem. Another trick is to boil inductor-cores/coils in oscillator and VHF/UHF filter and multiplier circuits to aid temperature and mechanical stability by removing the internal stresses in the cores and windings; as a bonus, the inductor is also sealed against moisture effects. Great video & 73...
Love the inductor core idea... Never considered if work hardened copper had any effect, sure can imagine movement in the coil doing so though?? Annealing copper requires new crystal growth and takes half an hour..maybe less for tiny cross section coils... at half melting point 4-600 degrees. Doubt wax would be anywhere near that ... But maybe its some other effect? Reducing stress is annealing.
Thank you! I am very grateful to the American people and the president for the great help and I wish for better days. And to you Dan - many thanks, very much appreciated and greetings from Israel.
Problem reaction solution where we fund both sides and then the citizens get stuck in a horrible situation. Thanks for motivating me to dig into one of these things
@@wayneheigl5549 Not to mention abandoning all our military equipment over there. I liked it before when gas was $1.50 a gallon, we were exporting energy with a leader that could walk AND talk. Now 20%+ inflation, WW3 and operating off our reserves we need to defend ourselves. The "big guy" seems to be working for China to weaken America to allow them to have Taiwan? China/Taiwan war should be starting any moment now. Taiwan makes 90% of world's microprocessors and 60% of other semiconductors. Meanwhile, America makes NOTHING..
"You can't give these away unfortunately." Someone gave me a late 60s or early 70s heathkit that I enjoyed restoring. I use the word "restore" loosely, because the thing basically worked. It just needed cleaning and maintenance. Anyhow, I used it in college. It was a lot of fun.
"I got to start there so let's 17:49 diagnose the internal oscillator circuit before we do anything" (snip frying caps) "I'm thinking it's a problem with the internal oscillator 1:12:13 though because if I use the 60 htz I can it's almost perfect" This is pure gold.
This was a great project, especially the experimentation with driving out water of the caps. Our prayers go out to those caught in the middle of the chaos that they can have peace and clarity.
Well done as always! I particularly enjoyed this one, having wanted to own an oscilloscope when I was young and broke - I had a few old timers, Tek 564A, Heathkit OL-1 and O-10. Then after I turned 40, things changed and now I have Tek 2225, 2445, and a Heathkit IO-4235 - all picked up separately for a few bucks each. But now I know that a scope is primarily a design engineering tool - one can troubleshoot with them, but they're overkill for that. Oh well...
Those old Sylvanias were very, very popular and widely used TV repairman scopes in their day. You rarely see any photos of a repair bench from those days without one on the bench. I don't think there were Heathkits nor EICOs until the early 50's, so you can imagine a zillion guys getting back from the war wanting to get into TV repair, an industry that must have been exploding back then. So they bought Sylvanias. I did not know they were so primitive. I am comforted knowing that they used Loctal tubes, I should have suspected given Sylvania manufacture, due to their stimulative effect on Shango. (I always hated them, too) I'll bet your sweep nonlinearity is as a result of the thyraton sweep oscillator. They're not exactly known for linearity. They are really fairly crude. You could look at the sweep output of the 884 tube on your other scope, but I'll betcha the triangle wave from that 884 is definitely rounded at the top.
Huge amount of work for you to get it going, thanks for the dedication. You even cleaned the black spodge of the screen at the end!!! Hard to think that an uncalibrated 100khz scope is remotely useful but modern tech had to start somewhere and the value is in what we've all learnt today. This instrument would have been someone's pride and joy once and yes it still looks fantastic.
Very cool video... I have a couple old useless oscillators I'm going to try to fix but didn't know where to start, I know this stuff is basic to you but for a lot of us it's all new. Thanks for the great video as always!
Yet another great Video Mate, just love watching occasional shortcuts to repair, the power cord on this, classic ! Always so interesting, never stop bringing those vids on, entertaining & educational. Oh, and keep pushing YT to the limit. Cheers from Oz ! Baz
Brilliant video Shango! TH-cam just needs someone to offer an alternative and they will flock to it! Not an easy thing to do but definitely necessary! Thanks for posting and take care!
A similar version of an RCA oscilloscope's version and vision sits before me, do you want the RCA version, of it?? Yell, and it's yours, in Cali, just yell, and It'll be shipped to Cali... I''m dying, so what the hell.... Your knowledge and my respect (both) ride with you, Shango066.... To have these instruments of a long-forgotten day saddens me, they deserve rescue......
@@shango066 Email, and the items are yours...I rescued them once...They'll be crated and sent should you wish.... I rescued them from being trashed., a few caps is all that's necessary...
For a circle you need one to be a cosine wave and one to be a sine wave. Sine and cosine are the same wave just with a 90 degree phase difference. So you can create one from the other with the appropriate phase shifting network (ie. caps, or inductors and so on).
Brings back memories... I was in electronic tech school circa 1986 and had a work-study job through financial aid with the state. At the time, the state operated some mental hospitals and I spent a few months after school in the basement shop. There was a repair shop to fix electronics used in the facility and seemed like its heyday was probably in the 60s. There was a Knight branded scope similar to this one that must have been a kit someone assembled (found the manual even). Must have been the most miserable scope I have ever tried to use as of course nothing was calibrated and the horizontal sweep was not linear so a sine wave displayed appeared to change frequency as it swept. Had lots of fun defying death down in that basement with TVs and so on. I well remember that time I tried to swap in a used tripler that had its anode wire chopped off so I tried to splice it and no matter what I did I had 1 inch arcing from the joint to the nearest metal.
I remember that that horizontal linearity thing is quite normal. It is explained in for example Heathkit O-12 manual. That vertical ripple usually comes from PT because the tube is not magnetically shielded. You can short vertical signal in CRT socket and if the ripple stays, it does not come from vertical amp circuit, but magnetically.
Another great entertaining video, esp. for us old-timers who remember doing complete in-home setup, purity, convergence, etc. on the old round CRT color sets! As for this scope, I don't think anyone mentioned this, there should be some sort of screen cover with graticule crosshatch lines for referencing P-P voltage of signal.
Should there really be a graticule on this? Obviously newer scopes do but those have more stable calibrated circuitry. On this thing the sensitivity will vary greatly with power line fluctuations, tube conditions, etc.
Nice devices, so many years and still work. Retrace line is always visible in simple scopes, modern uses cathode modulator to dimm that retrace line, but for simple ones that visible line is fine. One of the simple way to dimm retrace is to connect CRT catode by 470p cap with anode of oscillator tube, it may not work if not in phase.
Hey Shango, To remove moisture from a device you could try putting the device in a vacuum chamber maybe even try in a vacuum chamber along with some kind of desiccant. Thanks for the video
You actually want the wax to go into the capacitor. The paper between the aluminum foils is impregnated with wax. Or oil in oil caps. The wax on the outside shell is just to seal it, which is the seal which is responsible for breaching and letting moisture in. The wire connections get weak when you heat them up, the trick is to not touch the wires until the capacitor cools, at which point the leads aren't fragile anymore.
I can see a very good reason to spend the time to cook the moisture out of those wax paper caps. If you have a display piece for a museum and you want to occasionally run it.
Really old components must all be checked. Time consuming yes it is but necessary as you will find some are OK. Yeah , it is time to replace the electrolytics for they will crap out over a short time even if they tested good two days ago. This is the first time I have ever seen a request video made by Shango. Very nice! I wonder if Mr. Carlson saw this vid?
The 6DJ8 in that Sencore scope is recommended by amp guru Merlin Blencowe for use in a Cascode circuit. It's a stacked pair of triodes to create a pentode-like amplifier.
There used to be some basic mods you can do to these old scopes to get a llittle better performance/stability out of it. Itmight make a good video to see those applied.
Please more test equipment Shango! Really enjoyable. Amazed you magicked up that old wax cap. Maybe you could do some more experiments with “reforming” them?
Absolutely 👍 as the horizontal deflection ramp voltage got higher the leakage increased and caused a non linear ramp so you got the bunching on the right side (the top of the ramp) 👍👍 good job love your videos man 😎 ps the retrace lines are normal on these old scopes
I have been wanting one of those massive sylvanias ever since I saw bandersentv drag two of them home. The larger form factor is neat and I like that green & white front design. His had these neat chrome accents down the side. I have a period correct scope cart that I have matched with a (still not working) Heathkit OM-3. The OM-3 is probably a much better scope, but those tiny screens...
I have that very same Sencore Scope. it was the one my father used in his TV shop. He had modified it so it could check Transistors. Ive run it up twice over the years and it comes on but jitters quite allot. I only keep it because it was my father's otherwise it would have been junked years ago.
@41:58 - Per basic frying physics, the moisture should create a steam barrier with positive pressure internally that should theoretically keep all of the wax out.
When I 1st went to video I saw what I thought was sausages in a pot as I watched I realized it was capacitors in the 80s I used a wave solderer and used transistors volume control ,resistors and diodes loved the video awesome your some troubleshooter
Fascinating and useful - all the basics on restoring an old oscilloscope. One thing missing from my experience- what if there’s no dot, or the dot goes away while you’re troubleshooting? But this was very, very helpful!
1:07:50 My guess is that the reason why the horizontal deflection is all compressed like that is most likely due to the sweep-oscillator's sawtooth waveform being distorted, probably due to loading effects.
The reason for using Loktal tubes is that Sylvania wanted their service instruments to be rugged enough to hold up to everyday field use. Personally I didn't expect to see a thyratron oscillator.
The horizontal sweep is generated by charging a capacitor through a resistor. That is going to generate an exponential decay where the voltage is changing faster at the beginning of the "decay" than it is at the end. If it was charging the capacitors through a constant current source, the voltage change would be very linear over time and the compression at the end of the sweep would not be compressed.
Its how it was made for years. Making current source with tubes would not be so easy. So instead you can use higher voltage and charge capacitor maximally to 1/10 of that source voltage.
The non linear sweep is caused by the charging curve of the relaxation oscillator. Two ways to cure that. One is to use a current source to charge the capacitor..... this was not implimented in these cheap scopes. The other is to increase horizontal gain and have a wide overshoot allowing you to use only the lower linear part of the curve. All these cheap scopes have this issue. The hum is probably caused by not having a shield on the CRT, these were critical. Reorienting the transformer in relation to the CRT will also help.
Had a new electricity capacity done that to me. Put a new one in a radio. Was working fine. Truth the radio off walk away and came back later and turn the radio on and the cap shorted. Had to take it a part and put other cap in and working fine. So old or new caps can short.
The trace is compressed on one side because the output of the horizontal oscillator is defective, not a perfect sawtooth, and is a higher frequency at the beginning of the sweep pulse than at the end of the sweep pulse.
as-salamu alaykum friends! As usual YT is evaporating all the comments regarding the first few opening sentences of this video. I welcome the open discussion on any topic but they just won't allow it.... shalom
I live how Waters, and Talib can literally try to incite riots, but then they say Trump did that. Call him a warmonger, but monger wars. I hope the draft that is coming includes all bipedal entities, or the draft dodgers will all identify as women.
I support that country with the flag and the blue star.
@@F40PH-2CAT🇸🇴
Of course
North Korea doesn't allow it either.
1:04:02 There is nothing wrong with your television set. Do not attempt to adjust the picture. Shango066 is controlling transmission. He will control the horizontal. He will control the vertical. He can change the focus to a soft blur, or sharpen it to crystal clarity. For the next hour, sit quietly and Shango066 will control all that you see and hear. You are about to participate in a great adventure. You are about to experience the awe and mystery which reaches from the inner mind to...The Outer Oscilloscope Restoration Limits!
Awesome !!
NICE!
As a young-un in the 60's, I considered whether or not they really could control my television set. I concluded that indeed they did, because they sent signals which caused my TV screen to behave as it did. However I did have ultimate control because I could change the channel🤓
@@cmans79tr7 In the '90's I precisely experienced that: I had a TV for 3 years, 2 weeks over warranty. I did what I never did before, I had to see a certain program so bad, that I put a note under the picture for a week so I was absolutely sure I did not mis it. At moment supreme I installed myself in front of the TV with drinks, food, and expectations for the 30 minutes experience. Camera's roled, promo's ended, and there the first introduction of the program..... disappeared in a flash of silence. The TV was out, nothing to see or hear but sweat and confusion. After 15 minutes I took out a screwdriver and DMM, opened the back of the TV, and started wondering where to begin. Ah, I see a fuse.... Open !... 2 Amp fast. Went and found a 3Amp slow, put it in, and the TV came to life, many minutes after the program ended. I was had.
That TV lasted for at least 7 years, 6 hours a day, with that same fuse, it never popped again.
From that day on I was (am) sure that some TV's are controlled from the outside, probably through mains modulation or maybe on the carrier. It had chips in the PSU, so possible in my book.
Thank you so much for taking the time to make this video, especially in light of the YT thought police. I have gotten into vintage electronics and have learned so much from watching your channel. Your efforts are NOT being wasted, not by a long shot.
Hello from Poland 🇵🇱 Shango, I train Ukrainian medics in battlefield emergency casualty medicine and evacuation. I have been watching your videos for 8 plus years, I use them to relax and forgetabout the war to the east. Thank you again brother
I took those classes and still have the triage kit tourniquets and all that
@@shango066 that is so cool brother, happy Halloween, here we call it all saints day, everyone goes to all graveyards and we clean all Graves put flowers and candles on them and the space station took a picture of Poland during that night showing all graveyards across the country shining briter then any of the cities. Love your videos Shango, thank you very much.
Watching this while building a 2GHz PLL synthesizer from microscopic smd components. The difference in technology is unreal, what a difference 50 years of advancement can make. Thats why your videos are soo interesting, showing the crude and crusty beginnings of electronics.
Smd is super good, but you are afraid to sneeze near such small spare parts, and when they fall on the carpet, they and that moment are remembered for a long time
The DOD found in IIRC the 1960s that you can de-drift some carbon resistors by baking them in an oven to get the humidity out of them.
I revived an old 60's Eico.. just for the coolness aspect. I also picked up a Hickok scope a few years ago. Woah, what a difference in build quality. Its like comparing an old American car to a newer German import. Exceedingly over engineered..double or triple the weight, double the tube count and also 3 neon bulbs inside. I'm guessing for voltage regulation in a few circuits. Still trying to get that Hickok going. HV issue and have replaced everyrhing already....CRT is ok, works in the EICO.. it's now a rainy day project.. Thanks for the slightly different content. It helped my theory of operation on these.
You can always build Mr. Carlson's curve tracer and use it with that. Really cool project anyway. I think it's worth restoration. Thanks for doing a video on it.
Er, Just had to say, its not Mr Carlsons curve tracer- Curve tracers have been around since well before Mr Carlson. He would tell you that too, it is a standard piece of equipment. Not having a go at either you or Mr Carlson , who is amazing, (and I'm sure you are too 🤠) just wanting things correct.
Shango, I have watched your video's for years. LOVE THEM ALL! I have learned so much just watching, you are inspiring and a great teacher! I also love your comments and your funny words you come up with. A while back, I purchased a Cobra 2000, yea a CB and of course I got the mouths on Ham Radio throwing out attitude. Its Radio for gosh sake! Due watching your video's I was able to just look at the radio and know what was wrong with it before I bought it. Made a deal with the owner and brought it home. Stuck it on the bench and repaired the PLL by replacing the chip. I wanted to go through it and replace WHAT needed replacing only. By no means would I consider myself great at electronics but since watching your video's I have more successes than failures. The Cobra only needed just a few parts replaced to bring it back totally and I have been offered a small wad of dough for it. Not for sale, by the way some of the mouths were trying to buy it. Not a chance after their snide comments. I believe in Radio we all have a common interest and should work together and stick together and lay back the differences. We all love our radios so yea a start right. I have been a Ham since the 80's and played with CBs in the late 60's so I love radios, does not matter one bit to me what kind of radio either! AM Broadcast, shortwaves, CB's, Ham Rigs. Hey if it is Radio I love it! Back to the point YOU ARE MY FAVORITE TH-camR AND I WATCH EVERY VIDEO YOU MAKE! ALWAYS LEARN SOMETHING! ALWAYS! If you are ever in my area, Blue RIdge Mountains, look me up, you have a place to visit and hang out Anytime! Love you Dude you are great!
If the 60Hz sine wave signal on the vertical and horizontal is the same, it will produce a line. If they are 90 degrees out of phase, it will produce a circle. I used to do a lot of experiments with picture tubes and CRTs. When I first started experimenting, I hoped two sine waves in phase would produce a circle!
Mmmmm...deep fried capacitors..my tummys a rumbling for an oil-infused treat....Love it!
I prolong my enjoyment of Shangos videos by watching at 0.5 speed!
You out did your self today. I laughed the whole time you were deep frying the caps. I was waiting for you to drop some corn dogs in. Always a hoot... Thanks.
Learned a lot over the years from your videos. Fixed quite a few of all American 5 tube radios thanks to your knowledge. Keep up the great educational videos my friend!
That pause after "and here's the gentleman's home made probe... " says it all HAHAHA. Comedy gold.
Deep frying paper wax caps, now I have seen everything. You never cease to amaze.. edit: I bet a vacuum pump and jar would dry them too, ha.
I was thinking about one of the freeze drying machines
Beware of the bad ACID!
It's your trip, so beware! LOL
How about storing the scope for a month with a 40Watt bulb inside.
I'm sure Shango was just playing about, the problem is not just moisture but the paper has undergone an irreversible change and has lost most all of the properties it had. It is now just some variable stuff of unknown quality holding the bits apart. What is known is it will break down at a much lower voltage, and does. As usual Shango does the unusual and fascinating things. I love it too, but here its pretty pointless to expect lasting results.
“…cigarette glaze…” lol
Love your troubleshooting skills and thought processes…as well as your “detours”!
I was always interested in how these worked . Deep fried capacitors is a new one for me!
Come to Scotland Corina, everything gets deep fried
Thanks for your efforts on the behalf of us who enjoy this old equipment and the memories of using it to diagnose and repair old technology. The "Let the good times roll" at the end broke me Way to go Shango! Todah rabbah.
Horizontal and vertical tied together will give you a diagonal line. You need to make one of the two 90 degrees in reference to the other with a cap and/or coil. Great video as always.
is that why that re-trace line was always present?
@@VegasCyclingFreak The retrace line is probably because there is no circuit to blank the beam when its returning to the left side.
@kti5682 Oh yeah, duh. I forgot about scopes having blanking circuits. It's been a while since I've repaired one. I know next to next to nothing about tube based o-scopes.
@kti5682 Could be something to do with circuit design. I wonder how an old tube Tektronix scope compares. Maybe they have a blanking circuit and these cheaper "off-brand" scopes didn't (= costs more).
@kti5682 The retrace time of this scope is fixed but the main travel speed is not. On the slower settings where the retrace time is a smaller percent I think the retrace line is noticeably less visible.
That capacitor shorting at the end is a good example of why I replace ALL electros when restoring old tube equipment whether they test good or not - especially on gear that a customer is paying to have restored / repaired. I don't want them calling me a few hours or days later saying it's not working or something isn't right.
Yes it takes a bit more time to cut them all out and replace, but it's worth it in the end.
wow, a new shango066 and Mr Carlsons Lab video. It's like Xmas today
Check back next week as Shango adds storage, delayed-sweep, FFT and increases the bandwidth to 500MHz!
Actually (as the lore goes) you are supposed to only increase the wax just above boiling-point of water; then leave them in for several hours so that the water egresses, and the wax then ingresses to displace any voids and seal the capacitor from further moisture entering. This was a common farm/depression-era practice, and did work for capacitors that were not real old, whereby internal corrosion is actually more of the problem.
Another trick is to boil inductor-cores/coils in oscillator and VHF/UHF filter and multiplier circuits to aid temperature and mechanical stability by removing the internal stresses in the cores and windings; as a bonus, the inductor is also sealed against moisture effects.
Great video & 73...
Love the inductor core idea... Never considered if work hardened copper had any effect, sure can imagine movement in the coil doing so though?? Annealing copper requires new crystal growth and takes half an hour..maybe less for tiny cross section coils... at half melting point 4-600 degrees. Doubt wax would be anywhere near that ... But maybe its some other effect? Reducing stress is annealing.
Thank you! I am very grateful to the American people and the president for the great help and I wish for better days. And to you Dan - many thanks, very much appreciated and greetings from Israel.
Problem reaction solution where we fund both sides and then the citizens get stuck in a horrible situation. Thanks for motivating me to dig into one of these things
that (CLOWN) did not help you , he only does things for him, ask him why he gave 6 billion dollars to your enemy so he could get 10% kick back.
@@shango066 Wars: its politicians who start them and citizens who suffer and die ☮️
@@wayneheigl5549 Not to mention abandoning all our military equipment over there. I liked it before when gas was $1.50 a gallon, we were exporting energy with a leader that could walk AND talk. Now 20%+ inflation, WW3 and operating off our reserves we need to defend ourselves.
The "big guy" seems to be working for China to weaken America to allow them to have Taiwan? China/Taiwan war should be starting any moment now. Taiwan makes 90% of world's microprocessors and 60% of other semiconductors. Meanwhile, America makes NOTHING..
Baked and deep fried, been handed down through the ages by the Shango's and now to us. I feel humbled...cheers.
"You can't give these away unfortunately."
Someone gave me a late 60s or early 70s heathkit that I enjoyed restoring. I use the word "restore" loosely, because the thing basically worked. It just needed cleaning and maintenance.
Anyhow, I used it in college. It was a lot of fun.
Now this is something I have never seen before! Deep fried capacitors!
In Scotland they fry all sorts of odd stuff !
Nice of you to take that special request.
"I got to start there so let's 17:49 diagnose the internal oscillator circuit before we do anything"
(snip frying caps)
"I'm thinking it's a problem with the internal oscillator 1:12:13 though because if I use the 60 htz I can it's almost perfect"
This is pure gold.
2 thumbs up!! One for helping the soldier and one for the video!!
Love your channel, as always. Thanks Shango.
This was a great project, especially the experimentation with driving out water of the caps. Our prayers go out to those caught in the middle of the chaos that they can have peace and clarity.
Well done as always! I particularly enjoyed this one, having wanted to own an oscilloscope when I was young and broke - I had a few old timers, Tek 564A, Heathkit OL-1 and O-10. Then after I turned 40, things changed and now I have Tek 2225, 2445, and a Heathkit IO-4235 - all picked up separately for a few bucks each. But now I know that a scope is primarily a design engineering tool - one can troubleshoot with them, but they're overkill for that. Oh well...
Deep fried capacitors! Yeah! Could be handy for the professor fixing the radio on Giligan's Island, or after the apocolypse! Love it, only Shango! 😊
Wow, this thing needed a LOT of work.
That damp environment certainly took it's toll on the components.
Correct about the carbon comp resistors. First heard about this on Mr. Carlson's Lab.
Those old Sylvanias were very, very popular and widely used TV repairman scopes in their day. You rarely see any photos of a repair bench from those days without one on the bench. I don't think there were Heathkits nor EICOs until the early 50's, so you can imagine a zillion guys getting back from the war wanting to get into TV repair, an industry that must have been exploding back then. So they bought Sylvanias. I did not know they were so primitive. I am comforted knowing that they used Loctal tubes, I should have suspected given Sylvania manufacture, due to their stimulative effect on Shango. (I always hated them, too)
I'll bet your sweep nonlinearity is as a result of the thyraton sweep oscillator. They're not exactly known for linearity. They are really fairly crude. You could look at the sweep output of the 884 tube on your other scope, but I'll betcha the triangle wave from that 884 is definitely rounded at the top.
It's amazing how many good things get thrown away. They are still quite capable of performing their functions.
Huge amount of work for you to get it going, thanks for the dedication. You even cleaned the black spodge of the screen at the end!!! Hard to think that an uncalibrated 100khz scope is remotely useful but modern tech had to start somewhere and the value is in what we've all learnt today. This instrument would have been someone's pride and joy once and yes it still looks fantastic.
Shango. Love your videos. Very informative. I get the humor in your commentaries. Keep up the good work 👍
I've ALWAYS wanted to try boiling caps in wax, but never had enough wax or a hotplate I could use outside. Thank you for doing this!
Very cool video... I have a couple old useless oscillators I'm going to try to fix but didn't know where to start, I know this stuff is basic to you but for a lot of us it's all new. Thanks for the great video as always!
Hey Ron !
Come on people!
They're broke.
Yet another great Video Mate, just love watching occasional shortcuts to repair, the power cord on this, classic !
Always so interesting, never stop bringing those vids on, entertaining & educational.
Oh, and keep pushing YT to the limit.
Cheers from Oz !
Baz
"The new Botox commercial"...You had me rolling on the floor, Shango!
I learned a great deal with this particular video and I ( HAD ) been subscribed for 7 years
Deep fried capacitors & power lead testing. Most enjoyable viewing. 👍
Special request or not, I enjoyed this repair very much.
Thank you shango066
Brilliant video Shango! TH-cam just needs someone to offer an alternative and they will flock to it! Not an easy thing to do but definitely necessary! Thanks for posting and take care!
oh but there are several alternatives. they just dont offer the same resources
As usual you are amazing! You go places that I thought I'd get to go. I love that tube tester! Thanks for your videos!
Wonderful video, totally enjoyed this on a cold holiday weekend morning...
A similar version of an RCA oscilloscope's version and vision sits before me, do you want the RCA version, of it?? Yell, and it's yours, in Cali, just yell, and It'll be shipped to Cali... I''m dying, so what the hell.... Your knowledge and my respect (both) ride with you, Shango066.... To have these instruments of a long-forgotten day saddens me, they deserve rescue......
well.....
@@shango066 Email, and the items are yours...I rescued them once...They'll be crated and sent should you wish....
I rescued them from being trashed., a few caps is all that's necessary...
Frying capacitors sounds like a fun activity on Halloween.
For a circle you need one to be a cosine wave and one to be a sine wave. Sine and cosine are the same wave just with a 90 degree phase difference. So you can create one from the other with the appropriate phase shifting network (ie. caps, or inductors and so on).
Those old oscilloscopes are so cool looking when they're running! Excellent repair/rebuild video. 🙂
Brings back memories... I was in electronic tech school circa 1986 and had a work-study job through financial aid with the state. At the time, the state operated some mental hospitals and I spent a few months after school in the basement shop. There was a repair shop to fix electronics used in the facility and seemed like its heyday was probably in the 60s. There was a Knight branded scope similar to this one that must have been a kit someone assembled (found the manual even). Must have been the most miserable scope I have ever tried to use as of course nothing was calibrated and the horizontal sweep was not linear so a sine wave displayed appeared to change frequency as it swept.
Had lots of fun defying death down in that basement with TVs and so on. I well remember that time I tried to swap in a used tripler that had its anode wire chopped off so I tried to splice it and no matter what I did I had 1 inch arcing from the joint to the nearest metal.
I remember that that horizontal linearity thing is quite normal. It is explained in for example Heathkit O-12 manual. That vertical ripple usually comes from PT because the tube is not magnetically shielded. You can short vertical signal in CRT socket and if the ripple stays, it does not come from vertical amp circuit, but magnetically.
Great wax reform technique.... I think the hot wax is ideal to remove moisture but not blow up or dissolve cap, at correct temperature.
There is not only humidity, but also paper degradation, so it can help for while, but cant turn paper degradation back.
Cooking with Shango, I love the smell of deep-fried wax paper caps in the morning. Smells like victory!
Another great entertaining video, esp. for us old-timers who remember doing complete in-home setup, purity, convergence, etc. on the old round CRT color sets! As for this scope, I don't think anyone mentioned this, there should be some sort of screen cover with graticule crosshatch lines for referencing P-P voltage of signal.
Should there really be a graticule on this? Obviously newer scopes do but those have more stable calibrated circuitry. On this thing the sensitivity will vary greatly with power line fluctuations, tube conditions, etc.
Great video, I like when they are more than just working. Seems like a nice scope.😊
Nice devices, so many years and still work. Retrace line is always visible in simple scopes, modern uses cathode modulator to dimm that retrace line, but for simple ones that visible line is fine. One of the simple way to dimm retrace is to connect CRT catode by 470p cap with anode of oscillator tube, it may not work if not in phase.
Hey Shango, To remove moisture from a device you could try putting the device in a vacuum chamber maybe even try in a vacuum chamber along with some kind of desiccant. Thanks for the video
സംമ്മദിച്ചു.🙏🇮🇳🌹
You actually want the wax to go into the capacitor. The paper between the aluminum foils is impregnated with wax. Or oil in oil caps. The wax on the outside shell is just to seal it, which is the seal which is responsible for breaching and letting moisture in.
The wire connections get weak when you heat them up, the trick is to not touch the wires until the capacitor cools, at which point the leads aren't fragile anymore.
Wire connection gets weak because of excessive temperature. For boiling water (moisture) inside you need 100°C, solder melting occurs over 200°C.
I can see a very good reason to spend the time to cook the moisture out of those wax paper caps. If you have a display piece for a museum and you want to occasionally run it.
Really old components must all be checked. Time consuming yes it is but necessary as you will find some are OK. Yeah ,
it is time to replace the electrolytics for they will crap out over a short time even if they tested good two days ago. This
is the first time I have ever seen a request video made by Shango. Very nice! I wonder if Mr. Carlson saw this vid?
The 6DJ8 in that Sencore scope is recommended by amp guru Merlin Blencowe for use in a Cascode circuit. It's a stacked pair of triodes to create a pentode-like amplifier.
There used to be some basic mods you can do to these old scopes to get a llittle better performance/stability out of it. Itmight make a good video to see those applied.
Please more test equipment Shango! Really enjoyable. Amazed you magicked up that old wax cap. Maybe you could do some more experiments with “reforming” them?
Watching those caps boil ... now realize just how much moisture they su k up over the years . MIND BLOWN ! 😂
Absolutely 👍 as the horizontal deflection ramp voltage got higher the leakage increased and caused a non linear ramp so you got the bunching on the right side (the top of the ramp) 👍👍 good job love your videos man 😎 ps the retrace lines are normal on these old scopes
I have been wanting one of those massive sylvanias ever since I saw bandersentv drag two of them home. The larger form factor is neat and I like that green & white front design. His had these neat chrome accents down the side. I have a period correct scope cart that I have matched with a (still not working) Heathkit OM-3. The OM-3 is probably a much better scope, but those tiny screens...
I have that very same Sencore Scope. it was the one my father used in his TV shop. He had modified it so it could check Transistors. Ive run it up twice over the years and it comes on but jitters quite allot. I only keep it because it was my father's otherwise it would have been junked years ago.
You'll own everything and you'll be happy.
Because Nothing is Everything.
SFC SO GOOD ( SHANGOO FRIED CAPACITORS)
@41:58 - Per basic frying physics, the moisture should create a steam barrier with positive pressure internally that should theoretically keep all of the wax out.
@1:02:00 Reminds me of the old Outer Limits opening......"don't try to adjust your TV, we have total control ....😅
You should swap out the 884 for a 6LX8 since they seem to be similar in terms of not wanting to oscillate 😂
In the "Parts Shop Time Capsule" video there was a Tektronix CRT oscilloscope on the floor that deserves a video
You discovered the Colonel's actual secret recipe! 11 Herbs and Spices (plus a few capacitors).
@43:21 the bubbles by the wire look like a bunny wabbit! Highlight of my week so far!
When I 1st went to video I saw what I thought was sausages in a pot as I watched I realized it was capacitors in the 80s I used a wave solderer and used transistors volume control ,resistors and diodes loved the video awesome your some troubleshooter
Fascinating and useful - all the basics on restoring an old oscilloscope. One thing missing from my experience- what if there’s no dot, or the dot goes away while you’re troubleshooting? But this was very, very helpful!
Very interresting video. Thank you shango.
1:07:50 My guess is that the reason why the horizontal deflection is all compressed like that is most likely due to the sweep-oscillator's sawtooth waveform being distorted, probably due to loading effects.
I was using a $50 Dumont oscillograph in 1980 that was even more primitive...but it worked.
The reason for using Loktal tubes is that Sylvania wanted their service instruments to be rugged enough to hold up to everyday field use.
Personally I didn't expect to see a thyratron oscillator.
Diagnose then recap as necessary (learned this from you), glad you stuck to your guns. NO RECAPACIDE!
The horizontal sweep is generated by charging a capacitor through a resistor. That is going to generate an exponential decay where the voltage is changing faster at the beginning of the "decay" than it is at the end. If it was charging the capacitors through a constant current source, the voltage change would be very linear over time and the compression at the end of the sweep would not be compressed.
Yes, but most of the linearity issues were caused by the leakage of the capacitors. It turned out almost perfect after changing the caps.
@@mrnmrn1 Yes. I spoke too soon.
Its how it was made for years. Making current source with tubes would not be so easy. So instead you can use higher voltage and charge capacitor maximally to 1/10 of that source voltage.
The non linear sweep is caused by the charging curve of the relaxation oscillator. Two ways to cure that. One is to use a current source to charge the capacitor..... this was not implimented in these cheap scopes. The other is to increase horizontal gain and have a wide overshoot allowing you to use only the lower linear part of the curve. All these cheap scopes have this issue. The hum is probably caused by not having a shield on the CRT, these were critical. Reorienting the transformer in relation to the CRT will also help.
id like to see more test equipment. this was a fun one!
I used the TV7 tube tester in the army back in the seventies.
Surprising for test equipment that all the tubes outlived almost all the solid state parts.
Shango made a 1940's-1950's Sci-Fi movie 👍🎥
This is going to be fun
Did you ever try gently sanding the Tube pins to improve contact continuity ? It worked for me almost every single time.
Had a new electricity capacity done that to me. Put a new one in a radio. Was working fine. Truth the radio off walk away and came back later and turn the radio on and the cap shorted. Had to take it a part and put other cap in and working fine. So old or new caps can short.
It's perfect for AM radio and audio amp repairs. 👍
No. It's way too slow to even look at the IF
@@shango066 Oh yeah. I did'nt think of that. My bad.
Could do am radio with a detector probe.
The trace is compressed on one side because the output of the horizontal oscillator is defective, not a perfect sawtooth, and is a higher frequency at the beginning of the sweep pulse than at the end of the sweep pulse.
Would love to see this used in some diagnostics