Grand Receiver Restoration Series - The GE CX371 Part 2 - The Amplifier And Power Supply!
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- čas přidán 11. 09. 2024
- Sit beside Mr. C. at the repair bench! Let's go over the amplifier and power supply chassis together. An in-depth schematic explanation along with some great Tech Tips! Let's test some of the factory components and see how "good or bad" they are, almost 65 years from their manufacturing date. Enjoy! For links, click the SHOW MORE tab below.
To learn electronics in a very different and effective way, and gain access to Mr Carlson's personal designs and inventions, visit the Mr Carlson's Lab Patreon page here: / mrcarlsonslab
Part 1 of this GE CX371 receiver restoration: • 1957 Barn Find Radio R...
Part 3 of this GE CX371 receiver restoration: • Radio Receiver Restora...
#learnelectronics #restorationvideos #restoration
To learn electronics in a very different and effective way, and gain access to Mr Carlson's personal designs and inventions, visit the Mr Carlson's Lab Patreon page here: www.patreon.com/MrCarlsonsLab
Me and my cousin are going to a Swap meet June 5th 2022 Sunday morning at 8 am in Milwaukee
Other hobbys lisining to records CDs and fmstreo on my Yamaha reciver
Where the link to download the pdf.
Hey Mr Carlson, the 4K video is great, the 60P not so much, especially with slow-moving or mostly stationary scenes. 60fps is good for catching motion, but completely unnecessary and a waste of bandwidth for the type of content you produce. What’s worse, it may prevent those who would be able to watch 4K 30P from enjoying your show in 4K. For example, even my late model premium TV struggles to play back 4K 60P. Just thought you might like to know and adjust accordingly. C-ya!
@@greggaieck4808 se ne mogu olakšati posao je brat ja vas pitam da je brat je ljubav t
In my 40 years plus of electronics repair I never knew those caps were oil filled. Well I’ll be dang. Enjoyed this episode. I’m with you on component lead placement and soldering.
Paul, I don't know if you ever taught electronics to groups professionally, but I am always interested in your videos for this very reason. Your ability to explain not only the detail of how to do these repairs, but also the philosophy behind them and still make it all interesting shows me your teaching skills are outstanding. Looking forward to the next video.
Second that comment. I found this channel just trying to learn board level repairs for game consoles, but I've keep coming back because the videos and explanations are fascinating!
I just restored the glass panels of my digital dash cluster from my car and was thinking of how time consuming it would be to video and explain all the procedures. All my respect to how good you do it. By the way, I appreciate the rare look at under Chassi antique dust.
Yay for 80s digital dashes! My parents had an 86 camry with that awesome multi color VFD display in it. Nothing ever looked as cool.
@@matthiasmartin1975 that was some cool stuff.
I liked that ford used vfd dot matrix screens in their dash information centers till like 08 or so... I think the heavy duty commercial vehicles used it even a few years ago, I remember seeing it in a 19 model RV. but I think it has to be gone now.
As someone that's done both, it takes about 10x as long...
You saved the life of thousands of terminal strips and tube sockets with your unsoldering technique alone. Worth the price of admission all by itself. Thanks.
Even a Curious Marc shout out. Nice.
You and "Mikrowave1" are my favorite You-Tube creators. I love the way you do your presentations and every time I watch your videos I learn something. Thank you!
The beauty of these CZcams channels are the different disciplines we find and adhere to. Sometimes these same disciplines are drilled into us as we learn by others and too through experience. I tend to give a broad brush of grace to other's and their way of doing things...so in turn I learn some new everyday.....
Also...when it comes to Restorations: I realize that some seem to focus on cost and keep an original part if it's within tolerance, and sometimes it's perfectly acceptable to do so. But I prefer to prioritize (as in seeing) the future of the set, meaning unless it's detrimental to change a component I do not hesitate and replace everything. Why? Because it may be another 50 years before that 100 year old cap/ resistor / tube or wire is then replaced. Just my opinion humbly submitted.
As always great video and series Paul. Thanks & look forward to the next.
work in aviation electronics for 34yr,,this brings back memories l enjoy you videos you know your stuff.
Wonderful episode Paul....kinda of a master class on electronics....you do know this stuff inside out. Very excited to see part3.... Thanks again for all this knowledge. It is priceless! Cheers!
I've missed your long restoration videos! I appreciate all of your hard work you've put into your lab and equipment so we can enjoy these videos!. Tip for the day I've learned is to use string and go behind the knobs and wrap string around the 1/4 inch shaft to pull the knobs off. It puts all the tension on the center. Best regards!
Awesome walk through on the schematic. Anyone with basic electronic skills can follow you as we "look over your
shoulder". You explain things so well! Looking forward to part 3.
Your tip on not necessarily 'hooking' wires to terminals - priceless. I have been doing it (guilt-stricken) for just a year or so. Now I have a blessing! Thanks!!
Dam that's a heavy duty well built receiver, I like that, Couldn't be in better hands, Mr. Carlson will have it working like new in no time.
Will you fuse the 120 VAC input line? It could easily be hidden inside. Great work. You're a wizard at explaining the role of individual components in the schematic. Thanks for the great learning experience.
Loved how you went over the schematic with so much detail, every little random "what's that for?" resistor and capacitor. Thank you for making these fantastic detailed videos.
You are welcome!
I don't know the first thing about "Electronic Component's". But Mr. Calson's Lab is my favorite YT Channel.
I’m here before I can actually watch the video because I checked the playlist. It showed a deleted video, and I was curious to investigate! It says that the video is still processing.
I can hardly contain my excitement!
Update: I’m here, the video is here, but it is still unlisted. I don’t know how I’ve made it here before the patreon plug.
I’m not going to watch it at this moment, because the video is literally 5fps 144p.
Update II: 360p is now available. I will watch the video, however the video is only 30fps. I’m willing to settle for this, because I’m tremendously excited!
Hi Paul. I just watched the latest episode with my lab buddy, Westinghouse. We were taking a break from restoring our 1935 Philco Model 60. This is great stuff. You do a lot of hard work producing these videos, and I'm grateful. Can't wait for the next installment.
I'm anxious to see the next part. I'm looking forward to seeing which caps were replaced and with what type.
All of those oil caps will likely be replaced. There are not really that many in the chassis anyway. As for the type? There are companies such as Mod Electronics that still make oil-filled caps. But they come at a premium price. Generally, those old oil capacitors are replaced with poly caps.
The video work is so nice on these. It is no picnic getting that just right, and not so easy doing the rest of the editing/uploading etc....... Just want you to know I notice how good your production work is too.
Thanks Leonard! This video took CZcams 12 Hours to produce. The video size was 71.1G (Gigs.) I may go back to 1080P as the the processing time is "WAY" to slow (at CZcams.) This video could have been up at 10AM this morning in 1080P. Compressing the 4K file is possible before upload, but then what's the point if I'm going to reduce it's playback quality.... Then CZcams compresses it further after I compress it. Looking like 1080P again.
@@MrCarlsonsLab please stay with 4k, enjoying the crisp picture on the tv br from Sweden
@@MrCarlsonsLab I actually was waiting as the video uploaded, as I found the processing video in the playlist.
@@MrCarlsonsLab I ran into a similar thing even with 1080P last time. 2 different processing times Low Res/High Res. I haven't tried the 4K. But that is excessive, 12 hours is brutal. I have always found your videos to be very easy to watch and enough definition to see the important stuff fine. Not only that it seems that I find one little thing I was unaware of in each of them.
@@MrCarlsonsLab I believe its worth it. The time youtube spends encoding 4K is not wasted I assure you. The clarity is great. It also is NOT just for the minority of users with 4k displays. Thanks to downscaling and the higher bitrate setting the picture to 4K on a standard FHD display graces us with "better 1080p" for lack of a better word. Of course if it takes too much time off your schedule maybe it's better to stay on FHD but as far as we as concerned; I believe we are a quite patient audience so a day or 2 of extra wait is not going to be then end of the world.
I built one of your capacitor testers several years ago. It's one of my most-used tools. I love it!
Thanks for your kind feedback!
I had heard that the reason components were hooked around securely on terminal strips in the past was because of the assembly line. Several people installed components as the chassis went down the line. Then a solder team would do the task of soldering afterward. The hook-over prevented components from falling out of position.
I was taught that it was best to create a good physical connection before soldering, whether splicing wire or installing leads on a terminal.
Didn't surprise me that just about all resistors & caps needed replacing. Never seen a leaking cap like that. Yikes! Love that trim trick. Remember dad doing that. Love your channel. Ready for part 3 of this beautiful receiver.
Hi Paul. I know now why I have noticed, but avoided watching any of your videos. I'm probly gonna have to go & watch all of them now! I'm so far behind reading all the comments, & all the replies to the comments, & replying to a few comments, that if I parrot what's already been said try to bear with me ok!
Congrats mate on a fantastic video! Your clear explanation of the various circuit blocks & signal paths & interactions, components & their characteristics, performance, load & fault symptoms, as well as the repair itself, well geez, what else would I need to sit back & be thoroughly entertained for a while, besides that radio when you've finished fixin her up? I have a sparky mate who I can talk to about this electrickery stuff to some extent, but everyone else around me, well, eyes glaze over & heads nod & smile...you know. But here finally there's someone to talk to, so youse are probly stuck with me now.
I had a real nice big old bakelite cabinet Astor valve radio I had been kinda restoring (over the last 40 years) that got cremated in the bushfires here a year or 2 ago. I had been replacing all the rubber insulated single strand wiring in it with aircraft teflon/fibreglass tinned wire. The rubber insulation had turned into clay, & my girlfriend's dad complained that he had to smack it round the ear sometimes to stop the crackling noise, so I grabbed it away from him quick smart in the interests of safety. It's like you just look at the wiring & a bit of insulation would fall off somewhere! I had not long previously acquired some of this super dooper wire from a friend, so I thought - "what better use for it than to really fix up that radio!" Yeah it was real good wire but the worst, most difficult I'd ever had to work with! Trying to get that insulation off? I could strip 5 wires per stanley blade or something stupid like that. Aircraft grade, more like spacecraft grade!
So I'd been replacing electros, valves & resistors bit by bit & I was gonna polish up the nice 2 tone bakelite cabinet, but not any more.
Being a technician before a musician, my brand new faulty valve guitar amp was soon in pieces. Apparently a Chinese made copy of a 15 watt Epiphone amp. I also got a copy of a Gibson Les Paul guitar, both for $1k, so hopefully they're pretty good. My oldest son was the drummer in a metal band at the time & I spose I got the bug during my 'midlife crisis'. I chose the guitar cos it looked the best! I had no idea how to play but just fell in love with the look of this guitar! All the pearl & different-coloured inlays, gold plated string adjusters! A thing of beauty just to look at! So yeah I'm fixing & modding my amp, which will be fun!
Hey Paul like you desoldering tip regarding your “Favorite Pilers”. That is a GREAT idea !! We were all thought to make that mechanical connection before soldering. Here’s one for you that I like, I use various size forceps, they too have ridges for gripping but they lock and can work as a 3rd hand because of their weight(if you use large enough one) and you can let them go the weight will with the soldering iron will do the work if you need a 3rd hand. Even if you do not need a 3rd hand I find because forceps lock and come in various sizes and shapes(some come with a curved radius) for me they work better. They are also much finer for chassis that are very busy with components you can get in there much easier. I am frequently using forceps. Though you’d enjoy another perspective.
Ricky from IBM, Ret Englewood Florida
Gee, thanks, I was just going to go to sleep. I guess not for the next hour. 😂
😆
Inspiring, as always. The very best for you and your beloved!
Your measured, methodical vocal cadence is inspiring. So many of us talk fast and say little (Elon being exception), or speak in confusing twists and turns, whereas your speech seems metaphorical of the scientific method.
Paul you have spent year studying many electric currents and tube uses. I here you talk so clearly and enjoyable lyrics voice. I am going to find a school to attend to build a great audio tube amp
thanks for embarking on this great series. love this radio. anxiously awaiting the portion addressing the r390.
Mr Carlson has the coolest multimeter ever, nixies FTW!
I could be wrong but that appears to be a cathodyne phase inverter due to the plate of the second triode is feeding one of the outputs and the cathode is feeding the other.
Nice old radio. Anxious to see the final results.
Great vid, Thanks Paul.
You are correct, the configuration is: One amplifier stage driving a Cathodyne phase inverter, driving two 6V6's.
You are one incredible teacher. Even though I have a fairly thorough understand of this stuff, I still really enjoy hearing you explain how it works.
Paul, I think my wife is mad at you . I have always been an electronics tinkerer as my father was a TV tech in t early 60's and in the 5 years he had, he ingrained a luv of all things technical.
After watching some of your videos I had to make room for another hobby in restoring old radios, building the test equipment yo come up with and even a couple scopes. One for my curve tracer and one for fun. Don't worry, she can't get to you now ye are in Ontario. As long as we don't move back to Alberta.😁
Keep up the great work, and hopefully we all can save more of these gems from the landfills and get the enjoyment from them again.
Hi Russell, I feel privileged to be that inspiration. Thanks for your kind feedback!
Seeing Paul shout out to Marc made my day. Keep up the awesome content guys.
Fantastic as usual, Paul. So, one thing I'll add to the wrapped component thing is beware of "order of ops" on some of those. When multiples are sharing the same eyelet and they're wrapped, it can be a real pain to figure out which one needs to go first or if they're knotted together; especially if they're completely hidden behind a massive wad of solder on the terminal and there's no visible ears to trim haha. Fun sentence. Anyway a helpful trick is heat and wiggle the parts around to force a cold joint to form and thereby make it a little easier to get them out the last bit.
Great idea! Good onya Nonya!
Your videos are awesome and the in-depth explanations are the best. Your channel by far is the best around for learning electronics and restoration. Seeing these great classics brought back to life is truly amazing! Keep up the awesome work and look forward to more great videos from the lab!
Thanks for your kind feedback!
Love it when you go deep into a schematic.
Excellent explanation of the schematics and the design intent of all the components . I took some electronics courses over 30 years ago. Also took industrial electronics, PLC, and Robotics courses back then. I was also an industiral repariman BEFORE I started designing semi-automatic machines and product test equipment . I left that behind back in 2000. I moved into product design in various industries. Now I design plastic injection related products. Did delve into some data destruction machines in 2014. Later Aircraft Evacuation Slides. Also did some work on Blood Counting Machines in 2015. I like the variety in my design career. But I always have loved the "magic" of discrete electronics.
this is a great receiver. I would love to restore it myself. Thank you for saving all these receivers.
You are welcome!
Old is Gold, long life span analog product.
Nice! A resistor network, carefully tweaked, to match the two half waves driving the push-pull power amplifier output stage.
Tried this on a Transistor version applying a similar principle in a 1 room single-bed workshop during the late 70s,
the only cellar room in the house the parents had deemed safe when set on fire at the time.
Unfortunately, the project was abandoned because this one was soon running out of BD 138 paired transistors while tweaking the pots that had made up the above network.😮💨
Once again, the 4K video ROCKS.
Great video Paul. These oil filled caps are new to me. Thank you
But, when I was in High School Electronics some 50 years ago, we were always taught to "make a good mechanical connection" at terminals (tubes, tie points, etc.) before soldering. My grade would have suffered. So I appreciate your comments on Point-to-Point soldering and I repent of my errant ways. 😉👍👍 I also agree with you about that type of tube socket -- they fall apart quite easily. Better to have Bakelite, resin or ceramic sockets than that type.
Hi, great channel. Your pronunciation of chassis makes me smile. I'm from the UK. It's shassey, not chassey lol. Love your attention to detail with describing things, other presenters assume you already know. Thanks.
Yeah that's right Andy! Us aussies & pommies need to learn the mericans how to talk propper! Lol! Nah it's all good. Like solder not soder! Huh?
Unprecedented way of unsoldering the components out of these leads.. thank you for enlightenment..👈😎📻👍🇨🇦
No problem 👍
I admire you for doing this! I'm an old tech and am humbled by your knowledge.
Sir, you are the 'Bob Ross' of Electronics.
Hi Paul Thanks for an excellent series, really informative from someone who knows their craft. In case anyone thinks you're OTT with you oil warnings... A number of years ago in Ireland dioxins that had been banned for decades started to turn up during random sampling of bacon products. It turned out that old transformer oil had been recycled and mixed in with modern o il which was used to dry grain. This grain was then fed to pigs and the dioxins in the transformer oil having contaminated the grain then contaminated the meat.
Wow, interesting story, thanks for sharing that!
Dioxins? Omg they're one of the most toxic chemicals around! I think some components may have used polychlorinated biphenyls (pcb's!), which are also dreadfully bad for us.
Thanks Paul for the focus on the technical know-how, as well as the testing. push pull and phasing used to be a bit of a mystery to me but I am getting the hang of it thanks to specialists like yourself. Can't wait for the next video.
Amazing content. Also the image and sound quality is superb.
Thanks, Mr. Carlson!
You're very welcome!
I'm getting ready to restore a 1937 Philco 38-116. Looking forward to learning all i can from you in this series.
I love the Nixie tube display in the Ohm meter!!
I love that HP meter! The Nixie display looks fabulous on-camera. Picked up a 3440A (wtih the +- tube!) and with just a good cleaning, it works great. The design was pretty innovative for the time, and is still plenty accurate for general use today. I had hoped to make a video about it, but maybe I'll just wait and learn something from yours instead...
You are a top notch teacher, I especially love how you guide us through the schematics. I'm learning a lot and hooked on these excellent presentations.
👍. N5KY
bravo you are the best, tnx. so match, respectful from the old BG.
Congratulations on posting your 200th video to this channel!
Paul you're still the best on You tube. Glad you explain in detail some of the reasons why things were designed as they were back then..... Learn the most from you and most professional on You tube. Can't thank you enough made my day. 73s Mike wb7qxu
Thanks for your feedback, and kind comment too Mike!
I have a AR88 inside the bfo can which looks like one of the IF transformers is stuffed the caps and resistors it is working but then took it apart and found the resistors had gone out of spec due to the heat I recon.
Replaced all the parts and the output improved.
Quite a job to get to the parts.
I thought I would mention this in case you start looking for the res and caps on the restoration.
Has anyone ever said you sound like Jim carey ? Love your videos.
Jeezus. That there's some skewed components. They must have run this thing long after those capacitors started to leak. Glad it's on your bench to fix it! 👍️
I recently restored a Leak amp and tested the resistance of the primary power txmr, the back emf caused by the fluke 87 leads caused the meter to lock up and give the impression the the primary was O/C
Sprague apparently still uses Clorinol in their motor run capacitors; I wouldn't be surprised if that's what they used to put in their PIO Bumble Bees. Nasty stuff, known to the State of Cancer to cause California.
The bean counters were at work in the phase inverter section. Plenty of room in the chassis for an additional 12AX7 or small signal pentode, which would let you use that existing dual triode as a LTP and give more gain than you'd ever need.
Very informative and well done!👍😀 Looking forward to the next video. Thanks again for the time you dedicate to produce these videos. Very much appreciated!!👌🙂👏
Excellent video and crystal clear explanations as always. Thanks!
9:30 thanks for the explanation on why these types of caps should not be left in circuit, I may have to show this section to the musicians who come into my shop with a amp and a bag of old failed caps and want me to replace them
another banger episode mr C. im coincidentally trying to learn about RF interference with audio amps (translation: my guitar pickup hears too much wiggles from the ether) and this is right on topic. unfortunately i fell asleep because you're so calming. its morning now & I dont remember what you said, but hopefully i learned by hypnotism during my sleep. will watch again tonight. cheers mate.
My goodness I LOVE your videos! I always learn so much. Even when others may see something as mundane I see it as a new thing. Such is the excitement of a newbie. A 63 yr old newbie. LOL s I mentioned in a separate message I am self taught. I had no one to learn from so I just started reading. I know just enough to be dangerous. Hahahahaha.
I would like to throw down a gauntlet, so to speak. I must admit it is in my wheelhouse of WW 2 radios. I would like to see you restore a WW 2 BC-611. This is a historic radio as it is the very first walkie-talkie. Back then they called it the "Handy-talkie".
Should be a piece of cake. LOL not.
Keep em coming Paul, this series is going to be just great! Can't wait for the next instalment. TFS, GB :)
Awesome! You use the same small flexible LED lamp I use on my bench. I have a pair of them actually but one of them is starting to flicker a bit. I've not a found a replacement style LED lamp as yet but they are awesome for bench use.
The problem is usually the switch, also check the connection on the power supply. Spray some contact cleaner in the switch and cycle it a bunch of times. This fixes my lamps all the time. I think the weak spots are the connections.
What a beautiful radio, I want one.
Thanks. Love your approach, whether it be to teaching or electronicky gadgets
Wow, this is a description beyond descriptions. Great job. I actually took pictures with one phone and made notes for my reference manual. The use of snubber capacitors in the output circuit as well as the addition of 1K stopper resistors in the grid path of the 6v6s. One thing I have always wondered about is why a capacitor is placed across the output transformer of a single tube amplifier? You're point by point description of the entire circuit makes the video! Thanks
Glad it was helpful!
Thanks Paul, enjoyed watching. Seen on 22-5-22 at 11:12 in the NL. pe1krx
I do a lot of work repairing or building audio amps. Your a correct when you say that all grounding in the PSU so be a a central point, ? We call it a star earthing (grounding) . On solid state amps you should also take the speakers ground to this point as well . A good video . I like you videos because you explain why things are done
Aren't most modern audio amplifiers differential input and output? TI and NXP seem to be that way, the only new amplifier I have that's single ended is an Infineon IRS2092.
Thanks for sharing such a wealth of knowledge, superb
My pleasure!
OMG, those Bumble Bee caps. LOL.
I would just swap out every resistor and capacitor in it. :)
That looks like 👍 a very sophisticated radio 📻. I REALLY like 👍 it. That’s when radios 📻 were REAL. I saw 👀, and have to watch part 1 of this. That dial looks almost like 👍 the instrumentation 🎷in an airplane ✈️. I’m so glad 🙂 that you’re restoring it. Even the color of that case goes with any decor perfectly 😍. Please keep these GREAT 😊 radio 📻 videos coming. Your friend, Jeff.
Now im hooked, really kooking forward to the next episode.
Thanx Paul for starting the first. Enjoy watching.thanx Ken from gpt ms
I ment the ge radio. Thanx Ken from got ms
My pleasure!
Hi Paul, the Benton Harbor boys taught me how to solder via their really well done instruction manuals. And, they always said to make sure you had a strong physical connection before you soldered. I always thought it was overkill, but hey, what did I know back then. Not much.
Heath had by far the best assembly manuals for their kits. Wish I had been around when they were still in business.
Thanks for all the explainations and your process.
My pleasure!
Good to follow the progress and learn from seeing it done. Thanks.
Cracking good teaching experience - so very much appreciated
Glad you enjoyed it!
Thank you for your time and effort, Mr. Carlson.
You are very welcome Ed!
@@MrCarlsonsLab Dit dit
I'm off-air right now (new roof w/10kW PV system - antennas all down), but we should set up 40-meter sked and arrange eyeball QSO.
@@MrCarlsonsLab: I'm on you Patreon, so, IM me.
TX.
Oil caps could have PCPs in them--toxic. Very common in old transformers.
I notice that you tested resistors in place but isolated (cut one lead. . .) on the caps. Depending on circuitry the resistors could have a (parallel) sneak circuit that would have altered test readings, though you seem to rely on the schematics to avoid this.
Mr Carlsan your GE Cx 371 shortwave radio Receiver is so awesome
Any chance when you do take out the old capacitors and the bad resistors (please leave the good ones in, even if there are only a couple!), you could do a simple single-shot time lapse and post that? I think it would be interesting to see all that work being performed, even if at warp speed.
Love the videos. Thanks.
👍
Perfect sunday morgning view. Thx for the interessting vid. :D
That amp had a hard life by the looks of it. Nice engineering there.
73 from M0IVC - CT9ABQ
Very detailed, high quality video that you have uploaded. Nice.👌
another fab video - many thanks Paul as always...
My pleasure David!
I love to hear about "new style resistors"... Thanks!
I bet when this is fully restored it would sound great. Great looking front panel as well can’t wait for part 3
So, this radio was not a communications receiver, but maybe like an upper middle or higher grade consumer rx? Just with the multipl chassis and such. It's really nice.
I looked at many of your CZcams videos and you are doing a very good job.
Can you making a video on how to locate a noisy transistor in an audio circuit. Most audio transistor testers will indicate that a noisy none transistor will test good on many transistor tester but they are noisy.
Thank you for your excellent video. It is amazing the quality of the equipment and your skills are mesmerizing to watch.