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
Awww i'm in New Bedford, Mass! Is that what it reads on the side of that cap? When i was a freshman in Electrical Engineering back in the 90s we took a tour of Aerovox. I thi k at that time they only produced large industrial capacitors.... I'm only 4min in, but if you're going to throw out that cap, i'd actually like to have it :D
is that lil repeter part 95 ? hahhahah o wait ur above the line hahhahahah.... nice lil tool. i wish they had one for cell phones lol.. here near champlain cell service sucks lol
I don't understand electronics but I have been watching your videos for about 4 years now. you are and awesome communicator and entertaining. My favourite's are when you modify a circuit to make it better than it originally was. I hope you continue to make great content well into the future. thank you for the entertainment over the years.
Have a video on what cap replaces the old cap . Straight forward , replace this old type with this Modern type . That's it , real simple with no why or what .
I've not worked on any of my radio collection in 10 years but after watching some of your videos I'm ready to resume. Thank you for reminding me of how much I enjoy bringing them back to life.
30:23 - I had a problem with 455Khz IF years ago. I was living in Bangor, Me. One of their AM stations, WABI, broadcasted at 910 KHz, *exactly double the IF* ! So, when tuning in, you'd get a beat-frequency that would go to 'DC' if tuned in correctly :) To fix the problem, I just jacked up the IF of the receiver and tweaked the oscillator to compensate.
FYI I worked for Delco Electronics in Kokomo, Indiana my entire career (1977 - 2008), and we made some of the best radio receivers, along with several firsts in the auto industry (first in-dash radio receiver, first push button receiver, first electronic ignition module). I would have been surprised if you weren't impressed by this radio. It's also possible that all cases were made in ivory and painted brown at the factory.
Delco built many high quality, well engineered products over the decades. Most people don't know anything about Charles F. Kettering today, but he fran Delco Labs and was a creative genius and a giant in the American auto industry.
29:20...Your "Power Antenna" lightly Inductive Coupled alignment creation is Deff the best "Non-Loading" non-Disruptive Rf/If alignment method ever seen !! ...Big thx for showing this Superior technique...
I was watching Adam Salvage and he was talking about how things are not made to be repaired just replaced. He was sharing about the disconnect young people have with learning how things work and how to repair things. He used cars as an example and how new cars are designed to not be fixed by the owner. So as with him, thank you for showing and passing a long your knowledge so just maybe these skills are not lost to time.
Excellent job Paul! Your genius antenna booster device works like a treat. Not having to physically connect equipment to the radio makes it the absolute ideal way to align a radio. No influence on the test radio, & perfect safety for the test gear! The huge difference after alignment demonstrates the sensitivity of the radio, & the perfection of your test gear! A restoration video of this receiver would be an excellent watch, where I'm sure you could make it perform even better, if that's even possible. Thank you!
WOW!..indeed. Can only imagine how full restoration of this receiver will improve the performance. This is going to be a solid project. Thanks for the video and work.
I did an ivory paint removal on a 1937 Bakelite Philco a few months back. Back in the 50s to 70s when the Lady of the home wanted a paint over restoration of the kitchen, the mother in laws wedding gift brown radio on top of the fridge received the color of the walls.
Can you align, and peak up a radio, without test equipment or very limited cost test equipment. And if so do a video on how you would carry that out. Obviously not expecting the results to be as perfect but still put the radio in to a good state of usability. Keep up the good work on the channel, just recapped my first Ekco U319 radio, inspired by you channel. And it works!! Or at least receives channels on all bands!! Thanks from the Norfolk Broads UK
If the alignment of an AM radio isn't too far off you can trim it up "good enough" without any equipment. Tune to a station, being careful to precisely adjust the tuning knob for greatest volume and clarity. Then adjust the IF trimmers for best signal. For front-end alignment it's closer to the standard procedure. Instead of using the specific frequencies in the manual substitute the frequency of a broadcast station that's in the same part of the dial. In other words, an AM station is just somebody else's signal generator. If you want to spend a few dollars (or pounds) there are cheap modern crystal-controlled variable frequency oscillators. Many of these are based on the Si5351 chip. These output an unmodulated signal so you'll need to use a voltmeter on the AGC line instead of the speaker output.
Look up a product known as "Tiny SA". It's a spectrum analyzer and RF generator with modulation option. For an old basic am radio it can do all you need for basic alignment. Also look up an RF wand, one end is made of ferrite, other end is brass. You can use it to determine how much more or less you need to tune inductive rf coils, slugs or antenna bar/coil assemblies. In a coil, you bring brass and then ferrite ends into them or proximity of them, if signal or frequency changes in direction you need with brass side, you need less inductance, ferrite side the opposite, more inductance. You can make the RF wand.
These old tube sets work a lot better than many people today would think. I've lined up many radios like this, and yes you can do it by ear. To get the signal into the set without connecting the signal generator directly to it, I just take a lead from the sig. gen., and make a loop of a few turns and simply place it near the set. I keep the signal low, so the a.g.c. in the set doesn't kick in, and line up the IF like that. So a signal generator and a good ear is all you really need!
Thanks a million Paul, for working on this great radio. I love old tube type radios. I will be anxiously waiting for the restoration on it. All the best from Gene in Tennessee. 😄
Two weeks have passed,since i have finished my last tube radio project, a nordmende Carmen 57,last Job was restuffing the power supply filter capacitor, 3x 50uF, restuffed with 3x 47uF 400 volt ones,and polishing all brass parts at the Front of the radio. Works perfect, no hum at all,amazing Sound quality. Even the original schematic is still intact, which is really helpful, for checking resistors, and all the voltages.
Those old tube radios predating the NRSC mask by several years have such good audio even with the dumbing down of the transmitter audio chain. I believe that a radio like this coupled with a well matched antenna at the transmitter site can come really close to fm ! Great audio bandwidth! Sometimes newer isn’t always better
The harder to find Delco model R-1236 with pushbuttons circa 1946. It actually came only in the ivory finish. The non push button version came in either ivory ( R-1234) or brown ( R-1235). Interesting "junk box" power booster antenna none like I have ever seen! Impressed by your cleverness using a Compactron Mr. Carlson. Of course I don' t want to possibly send a signal out to the whole neighborhood. Or do I? LOL. Excellent revival and alignment of an old tube receiver!
Very interesting part about those caps / elco's. Like you, I have the experience that most "cans" are "gone" after more or less 50 years. Even less, depending of the heat (from nearby tubes) they had to endure during their life. Thanks for uploading!
US buildings that used 110VDC, I found the Electra Hotel in downtown Chicago. It had a steam plant for heating, domestic hot water and to Generate its own electricity. In the room that I rented had a sign above the one outlet stating caution 110 direct-current. Got a tour of the boiler room it was quite impressive. (Talk about off grid)
Yes, the Edison DC house power was used for many years in the Chicago and New York area. The prime reason for series circuit tube filaments was to make a radio that would operate from both AC and DC.
@@mackfisher4487 Thanks for your response but, I can't make sense of some of the words. "Entreating" is a forceful urging or begging. "Elect" means chosen. I'm not sure what R&R means. I guess my working vocabulary is quite a bit different than what you are used to.
@@JohnGodwin777 Thank you for your response, that makes a lot more sense! I suspect in the early days of electrical power generation, a city would buy an engine and generator head, then run it at whatever speed seemed to work best for their particular setup. For instance, 15 years ago, I was living in Hamilton, Ohio. I discovered they were originally running a line frequency of 133 Hz. My guess is they discovered that you can get more power out of the generator if you spin it faster. That power was being used to power arc lamps, incandescent light bulbs, and brush motors (non-frequency dependant loads).
I think I'm going to start shopping for one of these All American 6 radios. They sound great. Although there aren't nearly the number of AM broadcast stations around as there were, There's still enough to make getting one worth while. Thanks Mr. C for another great video.
I've been missing these kinds of videos so thanks for making one. It's a trip down memory lane for me for when I first got into your channel about 4 years ago. I've really come a long way (and I've got a long way to go) with my electronic knowledge in that time. Thanks for being such a great teacher!
Finally a normal mr.Carlson video Also Richard from the channel Learn electronics repair tried to contact you about a rare tube filled thing if you were interested in it but your Email did not work or could not find it ... anyway you may want to contact him .. if he still has it .. tell him dutch told you about it it was a german device
Those old radios are fascinating. With that nice, high-quality I.F. section, this is the perfect kind of A.M. radio for tapping off the I.F. output and feeding into a synchronous detector. Many years ago, I had a six octal tube radio similar to this. Wish I had hung on to it.
Thanks Paul for your detailed instruction. I’m amazed how well an untuned rf stage works. The rf amp would appear to have a 3300 ohm resistor as a load
Very helpful restoration & Alignment tips...Very interesting how Delco Economically incorporated the Rf Preamp stage while using just a standard "2 Gang" AA5 non Rf preamp type variable capacitor Without losing any hot, sensitive, long Distance reception performance !! ...I would've Assumed a much Lower sensitivity performance with the compromised Un-tuned preamp Plate coupling design but it seems to deff work Very well !!
Blessed love my brother, Is it possible for you to repair a ham radio for me please an thanks, I watch your videos, and think you are the right guy for the task, I have learn a lot from you bro, You are great bro, watching from Jamaica west Indies !!.
Hello Mr. Carlson. I just got home after having triple bypass surgery. As you can imagine I have a lot of restrictions. But I enjoy you and you videos so much. I get to learn new things. For a while I was a Patreon member but had to stop for financial reasons. I have been watching you for around five years. I appreciate the older equipment BECAUSE they can be repaired and modified. It is probably my imagination but I think they sound better.
Very informative video. I didn't understand everything, but I'm learning. The more comprehensive the explanation, the more learning. Looking forward to the restoration. Thanks.
General Motors has been using Delco radios with Bose speakers for a very long time...both are great by themselves but awesome when combined :) I could receive radio stations from the Yucatan capital (at night) which was over 2500 miles away...it always amazed me how well they picked up signals.
Yes we do have fused plugs in the UK, but unless fused correctly by the equipment supplier, many will be found with too high a rated fuse. Also they are no substitute for a fuse installed in the radios at a rating more closely levelled at the consumption plus (over and some way above starting current). I often use 500ma or smaller fuses. The Uk 240V means lower current than in the US 110v equipment.
Nice radio Paul! The push-buttons instantly date the radio as the 1940's. The RF amp was a huge performance upgrade for the 5 tube RCA tube set. The pentagrid converter stage generates a huge amount of noise, de-sensing the radio but, with the RF amp, that noise is reduced 10 to 20 dB. To correctly fuse this radio, each line should be fused, and the fuses should be in the plug but, to my knowledge, no one makes such a plug. I like to double the value of the cathode resistor on the audio output tube of any 5 or 6 tube series string RCA tube set to reduce heat dissipation. The audio output is by far the hottest tube in the radio and generally cracks plastic cabinets. The filter electrolytic in this radio was obviously replaced at some point, those radios used paper cased electrolytics originally.
With a properly-polarized plug it's best if there's only a fuse in the hot side, otherwise if the neutral blows all the internals become live. If you want a fuse with a built-in plug, look at Christmas lights. Polarized ones have one fuse, nonpolarized ones have two fuses. Increasing the cathode resistor is definitely a decent idea. Doubling might be excessive but going from 150 to 220 should help without hurting power output too much.
@@eDoc2020 Thanks for your comments/suggestion on the polarized plug. Increasing the cathode resistor on the audio output reduces the maximum audio output power slightly, as well as increasing the B+ by a few volts. This modification will probably go unnoticed while in operation unless the radio is played at maximum volume. I typically use a cathode resistor value of 270 to 330 ohms for the 50L6/50C5.
@@billharris6886 I'd need to look at the specs but doubling the resistor probably cuts the output power by more than half. The bigger issue is probably distortion.
It's a nice and simple radio with some quirks - I'm pretty baffled by the chassis and signal ground connections. Aerovox looking fine and dandy enough for restuffing and while I'd certainly want to put the HV lytics inside the cardboard tube, its small diameter makse it impractical or impossible to do so. I don't tune IF filters by ear - I always do it by measuring the DC voltage on a demodulator diode after disconnecting the automatic gain control feedback line to the stages. Going back from last to first filter and reducing the signal level after I get to the sweet spot. I agree that tuning the IF filters often works wonders - it's a pretty easy adjustment provided you have a sine wave generator (even one that goes to 500k...1M) and a frequency counter to ensure precision.
I've done them both ways, and I don't detect much discernable difference in the results. Tuning them by ear works just as well I have found, and in some cases even better. I learned all sorts of shortcuts aligning old tube automobile radios over the years, with excellent results, and saved a lot of time doing so.
Mr. carlson that is a perfect way of feeding the R.F. test signals to a radio, with built in antenna, via a remote antenna coil. I have done the same thing in my alignment of AM radios.
@@willjackson1955 YES! All the tube does is boosts the signal so the loop can be farther away from the radio being tested. Even several turns of wire to form a simple loop will work too.
@@JCWise-sf9ww nice, then I suppose that the tube is just an IF amplifier, a bit more broadly tuned to let all frequencies from 430 to 480 Khz pass? Thanks!
@@willjackson1955 I would say that Mr Carlson's device is a broadband RF amplifier driving an ordinary AM antenna coil without any tuning capacitor involved. With my knowledge, I would say the tube circuit & antenna loop is capable of amplifying & passing frequencies from about 100 khz into the HF (shortwave) range. Depending on the gain of the tube used, 50mv, from your generator, would easily be multiplied many times over. BTW: Carlson was also using the device as an Antenna re-transmitter.
Enjoyed this video, Paul and always look forward to keeping up with your latest installment. Love your new shop and your lift truck!! I wish the testing gear that you put out on your own was in kit form as I would purchase all of them just for the experience of putting something together that you designed but I do know there are just so many hours in a day and I do appreciate that you even make these inventions available to us. Thank You!!
I would love to see a restoration of this radio. Yes, you could leave it repaired and functional but if the option is there then why leave it at just a repair. A restoration would bring this radio back to its former glory as it was meant to be. I hope you decide to restore this beautiful piece of art from a simpler time. Greetings from Nevada, USA.
Good morning, this radio that you restored is very nice. I am amazed at the sensitivity it has in reception. I have some radios of this type, one of those is a Bendix 526 A. Greetings from Italy
Another excellent video, Paul. I love the way that you explain your procedures, for diagnosing and repairing electronic equipment. If my country wakes up, and votes for a businessman to run things again, then maybe I can afford to be a patreon in the near future!!
An awesome video and a real piece of electronic artwork. I absolutely love watching your videos and learning new tips and things I didn't know previously! A huge thank you!
thankyou sir for sharing your knowledge, experience and the best home lab, a dream home lab i wish i had. Your a gentlemen and i love watching your content,
35:40...The post-Realignment lab/basement sensitivity performance is Incredible !! ...Even without the Outside antenna connection, If you had turned Off all your other lab Equipment & other nearby Interference generating Sources, I bet it Would've picked up many Distant stations better than most "Today's" newest radios !!
It always fascinates me at how Vacuum tube using electronics are laid out and how much of the other components are still used today long after the tubes have cast aside for more modern components.
Great stuff love the vidoes. After starting to watch your videos some years ago I have since renovated many valve radio sets, sadly in the UK there is almost no MW or LW. Of an everning and using one of my ham antennas I can often pickup up chinese stations, for some reason. I shall be joining Patreon at some point soon. I really want to build a super probe, your capacitor tester and now you have that aerial thingy too.
I've gotten somewhat skeptical about published IF frequencies. Did a radio for a friend and noted that the cans were tuned to about 445kHz (not a typo.) I retuned them to the published 470 and found the dial wouldn't track worth a hoot, so I reset it back to 445 and everything was back to the way it should be.
Hmm, I have learned from You, that these Old, almost Ancient Radios, receive very well and this was long before Transistors and Integrated Circuits were invented
So when you end up with hum after replacing the multi-section capacitors, what sort of things should we look for to make it go away? I run into this when I'm doing my amateur restorations of radios like this or things like tube CB radios. I love the antenna 'caster' device! So handy and useful when you're working down in the basement like many of us are.
The remaining hum can be caused by heater-to-cathode leakage, poor lead dress, or in a 6 volt filament string, the same lead being used to ground the filament and cathode, particularly in the audio circuit.
Hi Paul .. I've been following you about 3 years, full of enjoyment. In fact you unwittingly motivated me to join the Ottawa Vintage Radio Club and talk up some of your creations. Awhile ago I loved your re & re of a Knight local AM transmitter ('intercom or baby monitor), and now I see your power amp is rather like a low-power a.m. transmitter. We're interested in the low-plate voltage 'space-charge' mode tube receivers, and now I'm wondering if low-voltage transmitter would work. Would be so much fun to see you explore space-charge tube radios: good projects for youngsters are in reach there. There were very early 'hikers' sets with one or two s.c. triodes.
Zap straps! Is that because they are attached to something electrical? 😜 And then you said zip ties! I can count on no fingers that I have heard of zap straps before I saw this video! Cable tie & zip-tie for the people of down under! 😁 Learn something new every day, besides the electronics that I love to watch! 👍
How are you? I hope you are very well. You are an inspiration to me, I watch every video of your channel. I think you are an inspiration name right so I think your videos should be released regularly which inspires me a lot. stay well Weren't you uploading videos to Facebook?❤❤❤❤
They switched the chassis side because the service receptacles and plugs were not polarized. Therefore, if the chassis side was connected to the hot side of the line it would be at full line voltage 24/7.
Thank you for doing the radio alignment on this Delco. I’ve had some difficulties learning how to do it. You made it simple to understand. If I may I’d like to ask a question not related to this video. I have an 1950 Buick with a 6 volt battery. I’m unable to jump start the car because the newer cars are 12 volt. Can you provide some information on how to drop the voltage to 6 volt if I use a 12 volt battery? Many thanks
Paul! I have been watching all your videos and they are so, so good! One thing: On your capacitor checker that has the LED lights. Would it be possible for you to put labels on the switches? It would be a nice touch got such a valuable electronic tester. Thanks and you are so good at trouble shooting!
![[MV] A leap of faith...ความเชื่อใจครั้งสุดท้าย (From "Petrichor the series")](http://i.ytimg.com/vi/U1piZH2CNXA/mqdefault.jpg)
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
Awww i'm in New Bedford, Mass! Is that what it reads on the side of that cap?
When i was a freshman in Electrical Engineering back in the 90s we took a tour of Aerovox.
I thi k at that time they only produced large industrial capacitors....
I'm only 4min in, but if you're going to throw out that cap, i'd actually like to have it :D
is that lil repeter part 95 ? hahhahah o wait ur above the line hahhahahah.... nice lil tool. i wish they had one for cell phones lol.. here near champlain cell service sucks lol
I don't understand electronics but I have been watching your videos for about 4 years now. you are and awesome communicator and entertaining. My favourite's are when you modify a circuit to make it better than it originally was. I hope you continue to make great content well into the future. thank you for the entertainment over the years.
Have a video on what cap replaces the old cap . Straight forward , replace this old type with this
Modern type . That's it , real simple with no why or what .
A complete restoration would be great to watch and then listen to it.
TY. I was having a bad day so I thought I'd listen to you and 45 minutes later the world seems like an okay place again. 🙂
Happy to make your day a bit better :^)
Great job. These are not just old radios, they are functional works of vintage art.
I've not worked on any of my radio collection in 10 years but after watching some of your videos I'm ready to resume.
Thank you for reminding me of how much I enjoy bringing them back to life.
30:23 - I had a problem with 455Khz IF years ago. I was living in Bangor, Me. One of their AM stations, WABI, broadcasted at 910 KHz, *exactly double the IF* ! So, when tuning in, you'd get a beat-frequency that would go to 'DC' if tuned in correctly :) To fix the problem, I just jacked up the IF of the receiver and tweaked the oscillator to compensate.
Neat
FYI I worked for Delco Electronics in Kokomo, Indiana my entire career (1977 - 2008), and we made some of the best radio receivers, along with several firsts in the auto industry (first in-dash radio receiver, first push button receiver, first electronic ignition module). I would have been surprised if you weren't impressed by this radio. It's also possible that all cases were made in ivory and painted brown at the factory.
Since there is just an AM band visible on the radio, what is the purpose of the red push buttons. Just curious. Thanks in advance.
@@fozzlac preset stations.
Dude Motorola and or Bosch/Blaupunkt made the.first auto radios
@@e.emerald3224 he said first IN DASH radio. In 1936, Delco began producing the first dashboard-installed car radios
Delco built many high quality, well engineered products over the decades. Most people don't know anything about Charles F. Kettering today, but he fran Delco Labs and was a creative genius and a giant in the American auto industry.
As an engineer myself it's so great to see this old radio working again. It also reminds us just how good some of these older tube sets were :-)
29:20...Your "Power Antenna" lightly Inductive Coupled alignment creation is Deff the best "Non-Loading" non-Disruptive Rf/If alignment method ever seen !! ...Big thx for showing this Superior technique...
I was watching Adam Salvage and he was talking about how things are not made to be repaired just replaced. He was sharing about the disconnect young people have with learning how things work and how to repair things. He used cars as an example and how new cars are designed to not be fixed by the owner. So as with him, thank you for showing and passing a long your knowledge so just maybe these skills are not lost to time.
Excellent job Paul! Your genius antenna booster device works like a treat. Not having to physically connect equipment to the radio makes it the absolute ideal way to align a radio. No influence on the test radio, & perfect safety for the test gear!
The huge difference after alignment demonstrates the sensitivity of the radio, & the perfection of your test gear!
A restoration video of this receiver would be an excellent watch, where I'm sure you could make it perform even better, if that's even possible. Thank you!
WOW!..indeed. Can only imagine how full restoration of this receiver will improve the performance. This is going to be a solid project. Thanks for the video and work.
I really like when you work on these types of radios!
Your stress relief on the power cord is a great idea!
I did an ivory paint removal on a 1937 Bakelite Philco a few months back. Back in the 50s to 70s when the Lady of the home wanted a paint over restoration of the kitchen, the mother in laws wedding gift brown radio on top of the fridge received the color of the walls.
Can you align, and peak up a radio, without test equipment or very limited cost test equipment. And if so do a video on how you would carry that out. Obviously not expecting the results to be as perfect but still put the radio in to a good state of usability.
Keep up the good work on the channel, just recapped my first Ekco U319 radio, inspired by you channel. And it works!! Or at least receives channels on all bands!!
Thanks from the Norfolk Broads UK
If the alignment of an AM radio isn't too far off you can trim it up "good enough" without any equipment. Tune to a station, being careful to precisely adjust the tuning knob for greatest volume and clarity. Then adjust the IF trimmers for best signal.
For front-end alignment it's closer to the standard procedure. Instead of using the specific frequencies in the manual substitute the frequency of a broadcast station that's in the same part of the dial. In other words, an AM station is just somebody else's signal generator.
If you want to spend a few dollars (or pounds) there are cheap modern crystal-controlled variable frequency oscillators. Many of these are based on the Si5351 chip. These output an unmodulated signal so you'll need to use a voltmeter on the AGC line instead of the speaker output.
Look up a product known as "Tiny SA".
It's a spectrum analyzer and RF generator with modulation option. For an old basic am radio it can do all you need for basic alignment.
Also look up an RF wand, one end is made of ferrite, other end is brass. You can use it to determine how much more or less you need to tune inductive rf coils, slugs or antenna bar/coil assemblies. In a coil, you bring brass and then ferrite ends into them or proximity of them, if signal or frequency changes in direction you need with brass side, you need less inductance, ferrite side the opposite, more inductance. You can make the RF wand.
My grin was directly coupled to the alignment stick as you tweaked up the signal. Reminds me of younger days out in my grandpa’s fixit shop.😁 📻
These old tube sets work a lot better than many people today would think. I've lined up many radios like this, and yes you can do it by ear. To get the signal into the set without connecting the signal generator directly to it, I just take a lead from the sig. gen., and make a loop of a few turns and simply place it near the set. I keep the signal low, so the a.g.c. in the set doesn't kick in, and line up the IF like that. So a signal generator and a good ear is all you really need!
Thanks a million Paul, for working on this great radio. I love old tube type radios. I will be anxiously waiting for the restoration on it. All the best from Gene in Tennessee. 😄
Two weeks have passed,since i have finished my last tube radio project, a nordmende Carmen 57,last Job was restuffing the power supply filter capacitor, 3x 50uF, restuffed with 3x 47uF 400 volt ones,and polishing all brass parts at the Front of the radio. Works perfect, no hum at all,amazing Sound quality. Even the original schematic is still intact, which is really helpful, for checking resistors, and all the voltages.
I really enjoy these videos. I always wanted to learn electronics, but time and other hobbies have trumped it.
Those old tube radios predating the NRSC mask by several years have such good audio even with the dumbing down of the transmitter audio chain. I believe that a radio like this coupled with a well matched antenna at the transmitter site can come really close to fm ! Great audio bandwidth! Sometimes newer isn’t always better
The harder to find Delco model R-1236 with pushbuttons circa 1946. It actually came only in the ivory finish. The non push
button version came in either ivory ( R-1234) or brown ( R-1235). Interesting "junk box" power booster antenna none like I
have ever seen! Impressed by your cleverness using a Compactron Mr. Carlson. Of course I don' t want to possibly send a
signal out to the whole neighborhood. Or do I? LOL. Excellent revival and alignment of an old tube receiver!
Very interesting part about those caps / elco's.
Like you, I have the experience that most "cans" are "gone" after more or less 50 years. Even less, depending of the heat (from nearby tubes) they had to endure during their life.
Thanks for uploading!
US buildings that used 110VDC, I found the Electra Hotel in downtown Chicago. It had a steam plant for heating, domestic hot water and to Generate its own electricity. In the room that I rented had a sign above the one outlet stating caution 110 direct-current.
Got a tour of the boiler room it was quite impressive. (Talk about off grid)
Yes, the Edison DC house power was used for many years in the Chicago and New York area. The prime reason for series circuit tube filaments was to make a radio that would operate from both AC and DC.
@@billharris6886 The early electrical history is entreating, like the reason for 1st elect R&R line voltage.
@@mackfisher4487 Thanks for your response but, I can't make sense of some of the words. "Entreating" is a forceful urging or begging. "Elect" means chosen. I'm not sure what R&R means. I guess my working vocabulary is quite a bit different than what you are used to.
@@billharris6886 I’m guessing he meant “intriguing” and “electrical”
@@JohnGodwin777 Thank you for your response, that makes a lot more sense! I suspect in the early days of electrical power generation, a city would buy an engine and generator head, then run it at whatever speed seemed to work best for their particular setup. For instance, 15 years ago, I was living in Hamilton, Ohio. I discovered they were originally running a line frequency of 133 Hz. My guess is they discovered that you can get more power out of the generator if you spin it faster. That power was being used to power arc lamps, incandescent light bulbs, and brush motors (non-frequency dependant loads).
I really liked the explanation of how a leaky Cap can read high, can't say I thought of that. 🙂
I think I'm going to start shopping for one of these All American 6 radios. They sound great. Although there aren't nearly the number of AM broadcast stations around as there were, There's still enough to make getting one worth while. Thanks Mr. C for another great video.
I've been missing these kinds of videos so thanks for making one. It's a trip down memory lane for me for when I first got into your channel about 4 years ago. I've really come a long way (and I've got a long way to go) with my electronic knowledge in that time. Thanks for being such a great teacher!
You're very welcome, and thanks for your kind feedback too!
Finally a normal mr.Carlson video Also Richard from the channel Learn electronics repair tried to contact you about a rare tube filled thing if you were interested in it but your Email did not work or could not find it ... anyway you may want to contact him .. if he still has it .. tell him dutch told you about it it was a german device
Those old radios are fascinating. With that nice, high-quality I.F. section, this is the perfect kind of A.M. radio for tapping off the I.F. output and feeding into a synchronous detector. Many years ago, I had a six octal tube radio similar to this. Wish I had hung on to it.
Thanks Paul for your detailed instruction. I’m amazed how well an untuned rf stage works. The rf amp would appear to have a 3300 ohm resistor as a load
Very helpful restoration & Alignment tips...Very interesting how Delco Economically incorporated the Rf Preamp stage while using just a standard "2 Gang" AA5 non Rf preamp type variable capacitor Without losing any hot, sensitive, long Distance reception performance !! ...I would've Assumed a much Lower sensitivity performance with the compromised Un-tuned preamp Plate coupling design but it seems to deff work Very well !!
That's a great gizmo you've invented, Paul. Nice radio too.
Looking forward to the restoration.
Blessed love my brother, Is it possible for you to repair a ham radio for me please an thanks, I watch your videos, and think you are the right guy for the task, I have learn a lot from you bro, You are great bro, watching from Jamaica west Indies !!.
Hello Mr. Carlson. I just got home after having triple bypass surgery. As you can imagine I have a lot of restrictions. But I enjoy you and you videos so much. I get to learn new things. For a while I was a Patreon member but had to stop for financial reasons. I have been watching you for around five years. I appreciate the older equipment BECAUSE they can be repaired and modified. It is probably my imagination but I think they sound better.
Hope you and the old' ticker are doing well!
Very informative video. I didn't understand everything, but I'm learning. The more comprehensive the explanation, the more learning. Looking forward to the restoration. Thanks.
I don't know half of what you're saying, but I love it. Haha!
General Motors has been using Delco radios with Bose speakers for a very long time...both are great by themselves but awesome when combined :)
I could receive radio stations from the Yucatan capital (at night) which was over 2500 miles away...it always amazed me how well they picked up signals.
our UK plugs all have a fuse . Awesome repair
Yes we do have fused plugs in the UK, but unless fused correctly by the equipment supplier, many will be found with too high a rated fuse. Also they are no substitute for a fuse installed in the radios at a rating more closely levelled at the consumption plus (over and some way above starting current). I often use 500ma or smaller fuses. The Uk 240V means lower current than in the US 110v equipment.
this piece of electric actuated art deserve a restoration!
Nice radio Paul! The push-buttons instantly date the radio as the 1940's. The RF amp was a huge performance upgrade for the 5 tube RCA tube set. The pentagrid converter stage generates a huge amount of noise, de-sensing the radio but, with the RF amp, that noise is reduced 10 to 20 dB. To correctly fuse this radio, each line should be fused, and the fuses should be in the plug but, to my knowledge, no one makes such a plug. I like to double the value of the cathode resistor on the audio output tube of any 5 or 6 tube series string RCA tube set to reduce heat dissipation. The audio output is by far the hottest tube in the radio and generally cracks plastic cabinets. The filter electrolytic in this radio was obviously replaced at some point, those radios used paper cased electrolytics originally.
With a properly-polarized plug it's best if there's only a fuse in the hot side, otherwise if the neutral blows all the internals become live. If you want a fuse with a built-in plug, look at Christmas lights. Polarized ones have one fuse, nonpolarized ones have two fuses.
Increasing the cathode resistor is definitely a decent idea. Doubling might be excessive but going from 150 to 220 should help without hurting power output too much.
@@eDoc2020 Thanks for your comments/suggestion on the polarized plug.
Increasing the cathode resistor on the audio output reduces the maximum audio output power slightly, as well as increasing the B+ by a few volts. This modification will probably go unnoticed while in operation unless the radio is played at maximum volume. I typically use a cathode resistor value of 270 to 330 ohms for the 50L6/50C5.
@@billharris6886 I'd need to look at the specs but doubling the resistor probably cuts the output power by more than half. The bigger issue is probably distortion.
High performance technician makes all the difference !!!!
It's a nice and simple radio with some quirks - I'm pretty baffled by the chassis and signal ground connections.
Aerovox looking fine and dandy enough for restuffing and while I'd certainly want to put the HV lytics inside the cardboard tube, its small diameter makse it impractical or impossible to do so.
I don't tune IF filters by ear - I always do it by measuring the DC voltage on a demodulator diode after disconnecting the automatic gain control feedback line to the stages. Going back from last to first filter and reducing the signal level after I get to the sweet spot. I agree that tuning the IF filters often works wonders - it's a pretty easy adjustment provided you have a sine wave generator (even one that goes to 500k...1M) and a frequency counter to ensure precision.
I've done them both ways, and I don't detect much discernable difference in the results. Tuning them by ear works just as well I have found, and in some cases even better. I learned all sorts of shortcuts aligning old tube automobile radios over the years, with excellent results, and saved a lot of time doing so.
They used that cabinet in many RCA sets, also. I have several.
I look forward to the restoration and multitude of tech tips you provide. Hopefully when testing at night you can receive KNX1070 from Los Angeles.
Mr. carlson that is a perfect way of feeding the R.F. test signals to a radio, with built in antenna, via a remote antenna coil. I have done the same thing in my alignment of AM radios.
Do you think that it would be doable by simply connecting a loop antenna to the 50Ohm output of a signal generator, without a tube in the middle?
@@willjackson1955 YES! All the tube does is boosts the signal so the loop can be farther away from the radio being tested. Even several turns of wire to form a simple loop will work too.
@@JCWise-sf9ww nice, then I suppose that the tube is just an IF amplifier, a bit more broadly tuned to let all frequencies from 430 to 480 Khz pass?
Thanks!
@@JCWise-sf9ww What amplitude are we talking about? My generator can do 50mV max...
@@willjackson1955 I would say that Mr Carlson's device is a broadband RF amplifier driving an ordinary AM antenna coil without any tuning capacitor involved. With my knowledge, I would say the tube circuit & antenna loop is capable of amplifying & passing frequencies from about 100 khz into the HF (shortwave) range. Depending on the gain of the tube used, 50mv, from your generator, would easily be multiplied many times over. BTW: Carlson was also using the device as an Antenna re-transmitter.
really enjoyed this... as I do all of your videos... Many thanks Paul... Great little radio...look forwards to the full restoration in due course.
Enjoyed this video, Paul and always look forward to keeping up with your latest installment. Love your new shop and your lift truck!! I wish the testing gear that you put out on your own was in kit form as I would purchase all of them just for the experience of putting something together that you designed but I do know there are just so many hours in a day and I do appreciate that you even make these inventions available to us. Thank You!!
I would love to see a restoration of this radio. Yes, you could leave it repaired and functional but if the option is there then why leave it at just a repair. A restoration would bring this radio back to its former glory as it was meant to be. I hope you decide to restore this beautiful piece of art from a simpler time. Greetings from Nevada, USA.
Sometimes i don’t know what he’s doing ,but I do enjoy it !
Restore it! I love the antenna device!
Great job Paul you make it look so easy.
Wow Paul great video! Keep them coming! I learn so much from you.
Another superb presentation. Looking forward to the restoration.
Good morning, this radio that you restored is very nice. I am amazed at the sensitivity it has in reception. I have some radios of this type, one of those is a Bendix 526 A. Greetings from Italy
Another excellent video, Paul. I love the way that you explain your procedures, for diagnosing and repairing electronic equipment. If my country wakes up, and votes for a businessman to run things again, then maybe I can afford to be a patreon in the near future!!
An awesome video and a real piece of electronic artwork. I absolutely love watching your videos and learning new tips and things I didn't know previously! A huge thank you!
Tanks Paul! Looking forward to this restoration!
Wish we was neighbors your having all the fun !
I love that the dial goes to 1700.
That's a cool little radio.
I see a not straight capacitor plate.
Cool! I've got an old 6 tube Motorola with the RF stage as well. She plays great after I changed out the filter capacitor.
Hooray!! Old radio restoration coming!!!!
I am really looking forward to seeing the Full Restoration of this radio.
thankyou sir for sharing your knowledge, experience and the best home lab, a dream home lab i wish i had. Your a gentlemen and i love watching your content,
35:40...The post-Realignment lab/basement sensitivity performance is Incredible !! ...Even without the Outside antenna connection, If you had turned Off all your other lab Equipment & other nearby Interference generating Sources, I bet it Would've picked up many Distant stations better than most "Today's" newest radios !!
Thanks Paul 🙂
Thanks for stopping by Dave!
Keep your grounds close, and your neutrals closer.
It always fascinates me at how Vacuum tube using electronics are laid out and how much of the other components are still used today long after the tubes have cast aside for more modern components.
Great stuff love the vidoes. After starting to watch your videos some years ago I have since renovated many valve radio sets, sadly in the UK there is almost no MW or LW. Of an everning and using one of my ham antennas I can often pickup up chinese stations, for some reason.
I shall be joining Patreon at some point soon. I really want to build a super probe, your capacitor tester and now you have that aerial thingy too.
Love your content man. I lost you for awhile and couldn't remember the name for the life of me but I found you again and I'm glad I did.
Welcome aboard!
Great video Mr C. Wish we made things like this agn.
LFOD !
Great video! I am excited to see the restoration.
What a great radio, your knowledge is amazing, thank you for making these great videos Larry Owens
Easiest. Radio. To. Rebuild. Love. Them. Very. Reliable
I can do anything except restringing the tuner, or rewind IF/RF coils. I'll pull the tubes and knobs then off to the curb it will go.
Mr C, you need to try the radio at night with an external antenna to see how many stations you can get.
Thanks for the video. I learned a lot. I have a similar Delco and you're right about performance, It's really a great performer. Take Care! 😀
I've gotten somewhat skeptical about published IF frequencies. Did a radio for a friend and noted that the cans were tuned to about 445kHz (not a typo.) I retuned them to the published 470 and found the dial wouldn't track worth a hoot, so I reset it back to 445 and everything was back to the way it should be.
Nice rx. It almost looked as if the two condensor vanes were moving at different rates!
I like the brown case with the white/ivory knobs!
Hmm, I have learned from You, that these Old, almost Ancient Radios, receive very well and this was long before Transistors and Integrated Circuits were invented
Your memory is amazing (!)
So when you end up with hum after replacing the multi-section capacitors, what sort of things should we look for to make it go away? I run into this when I'm doing my amateur restorations of radios like this or things like tube CB radios. I love the antenna 'caster' device! So handy and useful when you're working down in the basement like many of us are.
The remaining hum can be caused by heater-to-cathode leakage, poor lead dress, or in a 6 volt filament string, the same lead being used to ground the filament and cathode, particularly in the audio circuit.
Hi Paul .. I've been following you about 3 years, full of enjoyment. In fact you unwittingly motivated me to join the Ottawa Vintage Radio Club and talk up some of your creations. Awhile ago I loved your re & re of a Knight local AM transmitter ('intercom or baby monitor), and now I see your power amp is rather like a low-power a.m. transmitter. We're interested in the low-plate voltage 'space-charge' mode tube receivers, and now I'm wondering if low-voltage transmitter would work. Would be so much fun to see you explore space-charge tube radios: good projects for youngsters are in reach there. There were very early 'hikers' sets with one or two s.c. triodes.
High Performance Radio Receiver!
Zap straps! Is that because they are attached to something electrical? 😜 And then you said zip ties! I can count on no fingers that I have heard of zap straps before I saw this video! Cable tie & zip-tie for the people of down under! 😁 Learn something new every day, besides the electronics that I love to watch! 👍
Man I wish I could download all your knowledge into my brain!
Please restore it, Paul 👍👍
Paul, please include some information on what string would make a good string for the dial string replacement.
How are you?
I hope you are very well. You are an inspiration to me, I watch every video of your channel. I think you are an inspiration name right so I think your videos should be released regularly which inspires me a lot. stay well Weren't you uploading videos to Facebook?❤❤❤❤
I rewired the power switch on one of my radios to break the neutral going to the tube filament on the 12sq7 and used a polarized plug
Great Mr Carlson sir nice I enjoyed the show thanks for this video sir you are awesome ❤️ ❤😊❤
Zip-tie works for me.
They switched the chassis side because the service receptacles and plugs were not polarized. Therefore, if the chassis side was connected to the hot side of the line it would be at full line voltage 24/7.
Thank you for doing the radio alignment on this Delco. I’ve had some difficulties learning how to do it. You made it simple to understand. If I may I’d like to ask a question not related to this video. I have an 1950 Buick with a 6 volt battery. I’m unable to jump start the car because the newer cars are 12 volt. Can you provide some information on how to drop the voltage to 6 volt if I use a 12 volt battery? Many thanks
You can use an ESR meter on caps the “seem” to have gone up in value.
Thanks as always Carlson.
Thanks for this video of an awesome radio from my youth,, Am waiting now to see how you eliminate that annoying 60cycle hum,, and make it pretty,, :-)
As always, A+ Mr. Carlson.
Paul! I have been watching all your videos and they are so, so good! One thing: On your capacitor checker that has the LED lights. Would it be possible for you to put labels on the switches? It would be a nice touch got such a valuable electronic tester. Thanks and you are so good at trouble shooting!
Mrister Carlsons lab it is interesting when you look at schematics on antique radios my friend