I've been away from electronics since the late 80s. At 65 I got my ham liscence and been on a relearning curve for last three years. Thanks for this and other videos which finally give me a ahaaa moment . Your succinct explaination in a short video gelled so much info. Appreciated in this over the hill brain.
Thank you Rick, for such a basic walk-thru. It really pulls together so many things for me. This video is terrific, outstanding, really. You have really raised the bar with this recent graphic. I very much appreciate the time you put into these videos.
Thanks Rick for another great video. Watching your videos always seem to increase my understanding of topics I thought I knew. Thanks for re-educating an old HAM.
Totally awesome video Rick.... Your patience and expert teaching style have helped me to understand AA5 and other radios so well. It's really humbling trying to find the words to thank you for carrying this knowledge forward.....
Beautiful video how the radio signal goes through all the stages ,from the aerial to the loudspeaker and the AVC circuit very clearly explained how it works as well as the oscillator circuitry. The colouring of the path where the signals go through is simple wonderfully clear. Thanks for the very tutorial explanation and the clear lesson.
Thankyou for being a great mentor and teacher to us out here that are trying to learn. You do so much to help us understand.Great video,I just fixed my first radio ,a bad .02 cap leaking badly to ground on an old Hallicrafters s40a ham set.cut it loose and the old girl came to life with a new 1000 ohm resistor installed that was toast.
Your AM radio videos are the best I've viewed on TH-cam! I have learned so much from you! Thank You and keep them coming!I also downloaded you PDF book Thanks!
Thanks very much for getting back, I really appreciated it. This Astor BPJ I was working on was a customer repair, I have been doing this for nearly 5 years and have fixed all the sets I have worked on, probably about 40/50 or so and this fault was really doing my head in as he bought it on Ebay “working” and it had a few loose joints a broken leg of a new cap and a O.C resistor. I have been looking at this for weeks and trying different things, then yesterday the way you broke up this video in stages made me think if I connected some headphones to the input of the power tube after c15 in you schematic that may narrow down the fault which it did. So You did help me. So Thanks again.. Great video
That was a really great video! I've studied electronics and I got my diploma as a technician, but the course was really short (2 years) so we didn't have time to go too deeply into stuff like that. Now I understand how a radio works. That's really cool!
Really nice work Richard!! I particularly like the way you explained about the effective zero output of audio (signal cancelling out) if you tried to sample signal before it goes through the detector. Crucial information explained well. That was great fun to watch!
Rick, Thanks so much for showing, with your highlighted schematic, how an AA5 operates. I knew the basics, but your video shows all the details. The good news is that I can re-watch your video as often as necessary until it sinks in and takes hold. Regards, Tom
Wow Rick! I have been in electronics, professionally since the 70's and have NEVER seen a more definitive and clear presentation of how the signal flow in a radio schematic works in all my life. Bravo! If some day you could do the same for a vintage CRT based TV. This would also be absolutely fantastic. Excellent job! The pinnacle of demonstrations.
Thanks Philip Booth, R13 and R14 are biasing resistors. R14 races the voltage of the cathode 5.2V above ground, R13 sets the bias voltage at pin five for the control grid.
I realise that this is an old video,. but I have just come across it today. Thank You for a very clear and concise explanation of the signal flow through a radio. Your colouring of the signal path at the different stages makes everything very clear.
Fantastic video! Thanks. Nice refresher for me. BTW in describing the first IF you said the frequency that will be used was 455kc and 455Hz. Just wanted to mention that. Thanks for all your hard work
Thanks to you Rick. I'm finally getting it. I have found your videos extremely helpful. I've bought an old Grundig 5077 that needs work and I've been trying to do this myself. I'm a mechanical Engineer and so far my understanding has not been sufficient to do this. The radio has got Hum when you up the volume, Has poor FM reception and the volume periodically changes on its own. It has had most of the Caps changed (by the previous owner) but not all. I was finding the circuit very complex and difficult to follow but slowly with your tutorials it is coming into view. Very grateful to you for your clear and concise videos.
Thank you, and your welcome. I think my FREE eBook may help. PASSWORD is allamericanfiveradio drive.google.com/file/d/1HHmaWYr7UMACfmS4W5uL6PADoem2KlRp/view?usp=sharing
Very good explanation! I feel like someone just told me the secret to a magic trick that I've not been able to figure out. Understanding is a beautiful thing! You are an awesome teacher. Keep up the good work.
Thanks so much Richard... This is the best video on this aspect of radio that I have ever seen. This really helps to clear things up for me. Thanks for the downloads too.
Hi Rick, 13:06 running time but I know it took many hours in the making. I hope your work stays on TH-cam for many years as I'm sure your efforts will go a long way to help folk in preserving some lovely old radios that would otherwise bite the dust through lack of understanding. A very useful description in 13 minutes well done! Kind Regards ... Andy
Thanks Rick for this awesome video. I am trying to restore an old Hallicrafters S-38E which I believe is an AA5, just using a slightly different set of tubes. I appreciate all the effort to highlight the parts of the circuit as you were addressing them. This must have been a good bit of work but it makes your explanation very clear. Kind of funny, I just purchased a book about the AA5's on Amazon that appears to have been authored by you! Can't wait to get it! Thanks again. -rod (K1ROD)
Pin five, a plate, and pin three, the cathode, is a rectifier. It cuts the signal in half. The 155 pF capacitor drains off most of the 455 kHz signal and blocks the audio. The audio then travels down to the high side of the volume control.
Thanks GeoN0JRJ You're welcome to use this video for your ham club, I hope it helps the members to understand superheterodyne receiver's. The two links to the drawings I made to fit on an 8.5 x 11 sheet of paper. Hope this helps, Rick
@allamericanfiveradio I have an AA5 I just purchased in good condition works well and I assume the bulbs are still good. My only problem is that it only picks up one station and faintly picks up another. What can I do to help pick up more stations?
Thank you. These videos may help. Superheterodyne AA5 from End to End th-cam.com/video/glakoNN4lwA/w-d-xo.html Superheterodyne RF Mixer Visual Color Demonstration th-cam.com/video/OgU5aAzjR-k/w-d-xo.html Superheterodyne Radio, heterodyning frequencies together, how it works th-cam.com/video/5F-iKiltesU/w-d-xo.html
Thanks Douglas Tees I thought I sent a reply but I can't find it, must be another TH-cam improvement. In the circuit the vacuum tube would work better because it matches the impedance of the IF secondary. Generally, solid-state is more efficient but it is low impedance.
Thanks for a really detailed explanation, I guess I could troubleshoot an AA5 now without much trouble thanks to you, also helped with all valve radio troubleshooting.....................Ray H. ( from the U.K. ) Liked and subscribed.
Ain't was a very tuition way of explaining step by step the path of the signal from the aerial input to the loudspeaker including the circuit for the AVC according to the strength of the received signal . Thank you very much indeed. I think you should print a book accordingly , it would be a bestseller for the electronics basics.
Fantastic, fantastic video. It clarified a lot for me; albeit I'm late to the party! I just need to clarify for my self the AVC. If it reduces the negative to the grids, I thought that would lower the plate current!. I'll do more reading.
Thank you , and your welcome. Here are two videos that may help. Automatic Volume Level Control AVC ALC th-cam.com/video/NUerOOaKFP8/w-d-xo.html Superheterodyne AA5 from End to End th-cam.com/video/glakoNN4lwA/w-d-xo.html
AllAmericanFiveRadio I have a Emerson table top from 60s it has a 25 MFD 25 wv capacitor can I replace it with same kind or should I go to higher or different voltage than original. Also it has a 3uf 35wv capacitor also what do you recommend replace it with? In general what do you recommend I replace 2 capacitors with?
When replacing capacitors you should replace them with the closest matching microfarads to the original value. The working voltage should be at least the same or higher. Below is my free e-book. The Vacuum Tube Shortwave Radio www.richardmcwhorter.com/vacuumtuberadio/
Hi Richard. May I add a link to this video in one of my videos? This is such a great explanation of the AA5 I'd like to send viewers here if they would like to get a firm understanding of the AA5... -John
Rick, Your explanations for amplifier stage phase inversion, and detection are very clear. Much better than any textbook I have read besides yours of course. I have two questions. 1. When and how is the other detector plate pin 4 of the 12SQ7 used? 2. Is a vacuum tube detector more efficient than the galena crystal or say the 1N34A diodes used in crystal radio circuits?
I found the video very informative. I recap old shortwave receivers once in a while, and struggle with the flow of the schematics. Soon, I plan to recap a Zenith 6G601. 73 Paul AA1SU
Richard, When identifying the AVC/AGC line in any radio schematic, is there a surefire schematic landmark to go to first, for someone new, in finding/tracking it?
Beautiful! Thank you for this video. I have so much difficulty following these more complicated circuits and these 'signal trace' videos are very helpful and very much appreciated. I suppose the tube could be replaced with transistors?????
I have an RCA RC-1061,started to re tube and recap this radio. In over my head with it. Can I ship it to you for repair? ad5kd at alpha tango tango period November echo tango
I received a 5r10 hallicrafters and it is on as soon as it plugs in. The volume has an off but doesnt work, unless it clicks off hard? The powercord comes in with both lead going right to the first tube.- No switch. Also the r19 220 ohm 1w resistor is half broke and reads 120 ohm now. The tuning cord was routed wrong and had to be cut. I ended up just going from knob to pulley above it and it works! I left the back open to look at the variable cap to get an idea where in the frequency I am. Eventually I plan to fix the tuning cord & needle, atleast replace the broken resistor and put a polarized plugged cord on.
Rick great video I,ve been interested in tubes for a while and found your vid very informative. I got a late model AA5 a few years ago with the intention of re capping it as it has a very bad Hum.now i'm going to get to it this week.BTW i have a question what would happen if C17 was either shorted or open in the circuit? I have another radio which has one that is split open end from end and i get no sound at all just a slight whistling noise as i rotate the volume control>Thanks.jim
Great job! Could you please explain the purpose of the signal transformers? The output transformer is clearly to impedance match the tube driver to the low-ohmage speaker. But if the first I/F transformer is for adjacent signal rejection, what does the second transformer do?
Thanks jim maddog If C-17 opened the audio would have a high pitch to it, possibly generating noise. If C-17 shorted the audio output would be greatly reduced and possibly damage the 50L6 and the audio transformer.
That was the first, really clear explanation of signal flow I've encountered since I began playing with radios 50 years ago (Yikes, did I really say that? 50 years, phew.)
If the question is: for what purpose do you use the internet most of the time? Then watching, enjoying and learning from TH-cam channels like AllAmericanFiveRadio would definitely be in my top 3! I can’t thank you enough for all the time and effort you put in these video’s. Oh, and also thank you for the free ’The Vacuum Tube Shortwave Radio' E-Book I just discovered! Now I can watch one of your video’s, and then read, and than watch another video, and then read some more,…
Thank you for your personal reaction Richard, much appreciated. I can only hope you have as much pleasure making your video's than all we viewers have when watching them.
Thanks for this video Richard. I refer to it often. Can you tell me the purpose of the plate on pin #5 on the 12SQ7? I don't seem to get it cleared up in my mind. Everything else that you covered in good.
Pin#5 Plate and the Cathode are a Diode. This diode cuts the modulated RF in half so that the AM signal can be amplified. (AM Detection) This video may help you understand this process. If you have questions, let me know. How Superheterodyne Works th-cam.com/video/jQd2LfTOa4k/w-d-xo.html
I am working on a similar AM radio and I am not sure if the first tube on the left is OK or not. Basically I can find the adjustable tuning frequency of several MHZ on the grid but nothing comes out of the tube anode. The voltage is OK. Is that already a clear indication that the tube is damaged or could there be other problems (maybe on the antenna side )?
Oscillator Trouble Shooting Using Radios as Testers Demo th-cam.com/video/AuLP31cLBMQ/w-d-xo.html Portable Tube Radio Repair, Troubleshoot Oscillator problem th-cam.com/video/3PN92nLVqpo/w-d-xo.html
I have colored the section of each tube and labeled it's function. If you send me an email I'll send it to you, Make the subject Philips BX373A. allamericanfiveradio@yahoo.com
Really good explanations regarding the signal path and everything else within the radio. Thank you. Have subscribed. Just a beginner here trying to learn some radio basics. I have a question however, regarding the last part of the video (the Automatic gain control path via the R5). Why is it also tied to the Oscillator coil (B terminal) ? What does it do. ? Isn't that a somehow a typo on the drawing? Or. would that be a way to reduce the oscillators 455KHz level and in turn further reducing the overall amplification (in the event of a strong station ? Thank you.
R5 supplies the DCV stored by C8 for the ALC. It is common that a component has more than one function. C8 stores the ALC voltage, it isolates the OSC secondary from DC ground, and is the RF path for the OSC secondary to ground. I will do a video on this soon. Here are a few videos you many find helpful. How Superheterodyne Works th-cam.com/video/jQd2LfTOa4k/w-d-xo.html !923 Vacuum Tube, Amplitude Modulation Detector Circuit in Detail th-cam.com/video/e0faax3Svgw/w-d-xo.html MY FREE EBOOK Password is allamericanfiveradio th-cam.com/users/redirect?event=channel_description&redir_token=QUFFLUhqa2hhVTRycWdJd1FUbTFCZWNmdGtQNlZCRmEzd3xBQ3Jtc0tuOFQ2bFhRcWdjdUdIcUREcnZFaHc0M2xURGhITVRuWDE2cGlDakdYUF9uODktNzc3TVRJTWdROUt6R3NLN2lla3hFS2lIM0RnOXR1dXFxMGx2cUNtWDhXb1Zvc2RCbGQxTThoendmN2E5R0lJdmI0Yw&q=https%3A%2F%2Fdrive.google.com%2Ffile%2Fd%2F1HHmaWYr7UMACfmS4W5uL6PADoem2KlRp%2Fview%3Fusp%3Dsharing
I've been away from electronics since the late 80s. At 65 I got my ham liscence and been on a relearning curve for last three years. Thanks for this and other videos which finally give me a ahaaa moment . Your succinct explaination in a short video gelled so much info. Appreciated in this over the hill brain.
Thanks and your welcome.
Thank you Rick, for such a basic walk-thru. It really pulls together so many things for me. This video is terrific, outstanding, really. You have really raised the bar with this recent graphic. I very much appreciate the time you put into these videos.
Thanks again Rick. Once again just a fantastic presentation.
Thanks Rick for another great video. Watching your videos always seem to increase my understanding of topics I thought I knew. Thanks for re-educating an old HAM.
This is what I've been searching for, Rick. Thanks so much for posting it...
Totally awesome video Rick.... Your patience and expert teaching style have helped me to understand AA5 and other radios so well. It's really humbling trying to find the words to thank you for carrying this knowledge forward.....
Beautiful video how the radio signal goes through all the stages ,from the aerial to the loudspeaker and the AVC circuit very clearly explained how it works as well as the oscillator circuitry. The colouring of the path where the signals go through is simple wonderfully clear. Thanks for the very tutorial explanation and the clear lesson.
Thank you, and your welcome.
Extremely informative and thorough explanation. Thanks for taking all the time to put this together and providing the links.
Thanks
Thankyou for being a great mentor and teacher to us out here that are trying to learn. You do so much to help us understand.Great video,I just fixed my first radio ,a bad .02 cap leaking badly to ground on an old Hallicrafters s40a ham set.cut it loose and the old girl came to life with a new 1000 ohm resistor installed that was toast.
Thanks
Your AM radio videos are the best I've viewed on TH-cam! I have learned so much from you! Thank You and keep them coming!I also downloaded you PDF book Thanks!
Thanks
Thanks very much for getting back, I really appreciated it. This Astor BPJ I was working on was a customer repair, I have been doing this for nearly 5 years and have fixed all the sets I have worked on, probably about 40/50 or so and this fault was really doing my head in as he bought it on Ebay “working” and it had a few loose joints a broken leg of a new cap and a O.C resistor. I have been looking at this for weeks and trying different things, then yesterday the way you broke up this video in stages made me think if I connected some headphones to the input of the power tube after c15 in you schematic that may narrow down the fault which it did. So You did help me. So Thanks again.. Great video
Thanks
This video may help also.
Build a Audio and RF Signal Tracer using a Guitar Amplifier
th-cam.com/video/QUmPBBnzkRE/w-d-xo.html
That was a really great video!
I've studied electronics and I got my diploma as a technician, but the course was really short (2 years) so we didn't have time to go too deeply into stuff like that.
Now I understand how a radio works. That's really cool!
This may be a primitive design by today's standards however; you have to admire the brilliance of the engineers who designed it. Great video!
You may like this 100 year old circuit.
!923 Vacuum Tube, Amplitude Modulation Detector Circuit in Detail
th-cam.com/video/e0faax3Svgw/w-d-xo.html
Great video! I love the simplicity of the AA5.
Thanks
Really nice work Richard!! I particularly like the way you explained about the effective zero output of audio (signal cancelling out) if you tried to sample signal before it goes through the detector. Crucial information explained well. That was great fun to watch!
Thank you.
Rick,
Thanks so much for showing, with your highlighted schematic, how an AA5 operates. I knew the basics, but your video shows all the details. The good news is that I can re-watch your video as often as necessary until it sinks in and takes hold.
Regards, Tom
Wow Rick!
I have been in electronics, professionally since the 70's and have NEVER seen a more definitive and clear presentation of how the signal flow in a radio schematic works in all my life.
Bravo!
If some day you could do the same for a vintage CRT based TV. This would also be absolutely fantastic.
Excellent job! The pinnacle of demonstrations.
Thanks Philip Booth,
R13 and R14 are biasing resistors. R14 races the voltage of the cathode 5.2V above ground, R13 sets the bias voltage at pin five for the control grid.
I realise that this is an old video,. but I have just come across it today.
Thank You for a very clear and concise explanation of the signal flow through a radio.
Your colouring of the signal path at the different stages makes everything very clear.
Thanks
Thanks for the demonstration, very well put together.
Thanks
Fantastic video! Thanks. Nice refresher for me. BTW in describing the first IF you said the frequency that will be used was 455kc and 455Hz. Just wanted to mention that. Thanks for all your hard work
Thanks Joe Allen
Thanks Tony T.
Thanks for your generosity.
Thanks
Thanks to you Rick. I'm finally getting it. I have found your videos extremely helpful. I've bought an old Grundig 5077 that needs work and I've been trying to do this myself. I'm a mechanical Engineer and so far my understanding has not been sufficient to do this. The radio has got Hum when you up the volume, Has poor FM reception and the volume periodically changes on its own. It has had most of the Caps changed (by the previous owner) but not all. I was finding the circuit very complex and difficult to follow but slowly with your tutorials it is coming into view. Very grateful to you for your clear and concise videos.
Thank you, and your welcome.
I think my FREE eBook may help.
PASSWORD is allamericanfiveradio
drive.google.com/file/d/1HHmaWYr7UMACfmS4W5uL6PADoem2KlRp/view?usp=sharing
@@AllAmericanFiveRadio Thank you Richard. This is absolutely brilliant. You are most kind.
@@aspendesign Thank you, and your welcome.
Thanks John Richter
Very good explanation! I feel like someone just told me the secret to a magic trick that I've not been able to figure out. Understanding is a beautiful thing! You are an awesome teacher. Keep up the good work.
Thanks so much Richard... This is the best video on this aspect of radio that I have ever seen. This really helps to clear things up for me. Thanks for the downloads too.
Your welcome and Thanks
@@AllAmericanFiveRadio Sadly, links are now broken.
Very good, thank you for posting.
Thank you, and your welcome.
Hi Rick, 13:06 running time but I know it took many hours in the making. I hope your work stays on TH-cam for many years as I'm sure your efforts will go a long way to help folk in preserving some lovely old radios that would otherwise bite the dust through lack of understanding. A very useful description in 13 minutes well done!
Kind Regards ... Andy
Great video... love circuit walk throughs
Great explanation and very helpful.
excellent video, learned quite a bit on how superhet radio's work
Thanks sahhaf1234
Mostly want C-17 does, is it attenuates the high audio frequencies a little.
Thanks Ron Pearson
Thanks Rick for this awesome video. I am trying to restore an old Hallicrafters S-38E which I believe is an AA5, just using a slightly different set of tubes. I appreciate all the effort to highlight the parts of the circuit as you were addressing them. This must have been a good bit of work but it makes your explanation very clear. Kind of funny, I just purchased a book about the AA5's on Amazon that appears to have been authored by you! Can't wait to get it! Thanks again. -rod (K1ROD)
Thanks Cosmos142857
Yes, the flow for a basic transistor AA5 is the same.
Excellent video! Great analysis!
Thanks
Thanks Andy
Wow that was great , it was a very clear and easy to follow explanation . Thank you.
Thanks
Your videos are really nice!
Thanks
Thank you for sharing this knowledge. Marvelous!
THANK YOU!
excellent work
Thank you.
This was much better than just good. Many thanks, I learned a lot.
Your welcome.
Pin five, a plate, and pin three, the cathode, is a rectifier. It cuts the signal in half. The 155 pF capacitor drains off most of the 455 kHz signal and blocks the audio. The audio then travels down to the high side of the volume control.
Thanks AntiqueRadioandTV
Wow!!!! Old upload but so so informative. Thank you for the clear and concise explanation.
Thanks, age does not mater. The truth is the truth.
Thanks Joe Minor
Yes, I put a note in the video and I corrected the downloadable file.
Well done. Congratulations!
Thank you.
great explaination of the signal flows. thank you
Thanks and your welcome.
Thanks Philip Booth
Very nice and simpley stated. Thank you.
Thanks GeoN0JRJ
You're welcome to use this video for your ham club, I hope it helps the members to understand superheterodyne receiver's. The two links to the drawings I made to fit on an 8.5 x 11 sheet of paper. Hope this helps,
Rick
@allamericanfiveradio I have an AA5 I just purchased in good condition works well and I assume the bulbs are still good. My only problem is that it only picks up one station and faintly picks up another. What can I do to help pick up more stations?
Great lesson, Thank You!
Thank you Sir, i'm still learning the basics and this is very helpful. I don't completely get it but i'm starting to :)
Thank you. These videos may help.
Superheterodyne AA5 from End to End
th-cam.com/video/glakoNN4lwA/w-d-xo.html
Superheterodyne RF Mixer Visual Color Demonstration
th-cam.com/video/OgU5aAzjR-k/w-d-xo.html
Superheterodyne Radio, heterodyning frequencies together, how it works
th-cam.com/video/5F-iKiltesU/w-d-xo.html
Thanks Douglas Tees
I thought I sent a reply but I can't find it, must be another TH-cam improvement. In the circuit the vacuum tube would work better because it matches the impedance of the IF secondary. Generally, solid-state is more efficient but it is low impedance.
Thank you!
Thank you , that was a very informative video.
Thank you.
Thanks, I can understand the way you presented it. Lot of info
Thank you, and you may like this video also.
Superheterodyne RF Mixer Visual Color Demonstration
th-cam.com/video/OgU5aAzjR-k/w-d-xo.html
Thank you very much , good explanation of the signal flow
THANKS
Thanks for a really detailed explanation, I guess I could troubleshoot an AA5 now without much trouble thanks to you, also helped with all valve radio troubleshooting.....................Ray H. ( from the U.K. ) Liked and subscribed.
Thank you.
Thanks you Boss. I will try this on my equipment schematics
Thank you, and your welcome.
Ain't was a very tuition way of explaining step by step the path of the signal from the aerial input to the loudspeaker including the circuit for the AVC according to the strength of the received signal . Thank you very much indeed. I think you should print a book accordingly , it would be a bestseller for the electronics basics.
Muy bien explicado su video acerca del funcionamiento del receptor superheterodino, muchas gracias. CE1GWX, 73.
Thank you, and your welcome.
Thanks skycarl
Fantastic, fantastic video. It clarified a lot for me; albeit I'm late to the party! I just need to clarify for my self the AVC. If it reduces the negative to the grids, I thought that would lower the plate current!. I'll do more reading.
Thank you , and your welcome. Here are two videos that may help.
Automatic Volume Level Control AVC ALC
th-cam.com/video/NUerOOaKFP8/w-d-xo.html
Superheterodyne AA5 from End to End
th-cam.com/video/glakoNN4lwA/w-d-xo.html
@@AllAmericanFiveRadio Thank you
Great video!
Thanks I hope this video helps.
Thanks blackcorvo
Wonderful explanation. Thanks.
Thanks
Thanks for the great info.....
Thank you and your welcome.
AllAmericanFiveRadio I have a Emerson table top from 60s it has a 25 MFD 25 wv capacitor can I replace it with same kind or should I go to higher or different voltage than original. Also it has a 3uf 35wv capacitor also what do you recommend replace it with? In general what do you recommend I replace 2 capacitors with?
When replacing capacitors you should replace them with the closest matching microfarads to the original value. The working voltage should be at least the same or higher. Below is my free e-book.
The Vacuum Tube Shortwave Radio
www.richardmcwhorter.com/vacuumtuberadio/
Excellent lesson.
Thank you, and your welcome.
Thanks saturn5tony
Thanks for sharing!
Thank you.
Thanks iorixs
Hi Richard. May I add a link to this video in one of my videos? This is such a great explanation of the AA5 I'd like to send viewers here if they would like to get a firm understanding of the AA5... -John
John Richter
John RichterSure you can link to this video. I'm glad you like it.Rick
Rick, Your explanations for amplifier stage phase inversion, and detection are very clear. Much better than any textbook I have read besides yours of course. I have two questions. 1. When and how is the other detector plate pin 4 of the 12SQ7 used? 2. Is a vacuum tube detector more efficient than the galena crystal or say the 1N34A diodes used in crystal radio circuits?
I found the video very informative. I recap old shortwave receivers once in a while, and struggle with the flow of the schematics. Soon, I plan to recap a Zenith 6G601. 73 Paul AA1SU
THANK YOU!
Richard,
When identifying the AVC/AGC line in any radio schematic, is there a surefire schematic landmark to go to first, for someone new, in finding/tracking it?
Beautiful! Thank you for this video. I have so much difficulty following these more complicated circuits and these 'signal trace' videos are very helpful and very much appreciated. I suppose the tube could be replaced with transistors?????
I have an RCA RC-1061,started to re tube and recap this radio.
In over my head with it.
Can I ship it to you for repair?
ad5kd at alpha tango tango period November echo tango
I received a 5r10 hallicrafters and it is on as soon as it plugs in. The volume has an off but doesnt work, unless it clicks off hard?
The powercord comes in with both lead going right to the first tube.- No switch.
Also the r19 220 ohm 1w resistor is half broke and reads 120 ohm now.
The tuning cord was routed wrong and had to be cut.
I ended up just going from knob to pulley above it and it works! I left the back open to look at the variable cap to get an idea where in the frequency I am.
Eventually I plan to fix the tuning cord & needle, atleast replace the broken resistor and put a polarized plugged cord on.
I hope you can continue with the restoration, back to 100%.
Can you use a 455khz crystal where the first IF can is to do the same thing..???
455kHz crystal filter.
Thanks vibra64
Yes I put a note in the video and corrected the drawing
thank you.
Thank you, and your welcome.
very good very good very good .. best educational video i have ever seen
Thanks
Do you have any videos that explain some of these circuits individually? I am having trouble understanding.
Download my FREE ebook. You will the download link in the ABOUT on my TH-cam Channel.
Rick great video I,ve been interested in tubes for a while and found your vid very informative.
I got a late model AA5 a few years ago with the intention of re capping it as it has a very bad Hum.now i'm going to get to it this week.BTW i have a question what would happen if C17 was either shorted or open in the circuit? I have another radio which has one that is split open end from end and i get no sound at all just a slight whistling noise as i rotate the volume control>Thanks.jim
Thanks WillBdiggin
Great job! Could you please explain the purpose of the signal transformers? The output transformer is clearly to impedance match the tube driver to the low-ohmage speaker. But if the first I/F transformer is for adjacent signal rejection, what does the second transformer do?
The first IF filters out over 90%, the second IF filters out over 90% of whats left. So with two filters the usable signal is almost 100% pure.
@@AllAmericanFiveRadio Thank you for taking the time to explain.
@@TheCondoInRedondo Thanks and your welcome.
Thanks ranuts2
Thanks jim maddog
If C-17 opened the audio would have a high pitch to it, possibly generating noise. If C-17 shorted the audio output would be greatly reduced and possibly damage the 50L6 and the audio transformer.
That was the first, really clear explanation of signal flow I've encountered since I began playing with radios 50 years ago (Yikes, did I really say that? 50 years, phew.)
If the question is: for what purpose do you use the internet most of the time? Then watching, enjoying and learning from TH-cam channels like
AllAmericanFiveRadio would definitely be in my top 3! I can’t thank you enough for all the time and effort you put in these video’s. Oh, and also thank you for the free ’The Vacuum Tube Shortwave Radio' E-Book I just discovered! Now I can watch one of your video’s, and then read, and than watch another video, and then read some more,…
Thanks you Patrick. I'm glad that you find my TH-cam site useful. When I started my TH-cam I was wondering if any body would be interested.
Thank you for your personal reaction Richard, much appreciated. I can only hope you have as much pleasure making your video's than all we viewers have when watching them.
Thanks for this video Richard. I refer to it often. Can you tell me the purpose of the plate on pin #5 on the 12SQ7? I don't seem to get it cleared up in my mind. Everything else that you covered in good.
Pin#5 Plate and the Cathode are a Diode. This diode cuts the modulated RF in half so that the AM signal can be amplified. (AM Detection) This video may help you understand this process. If you have questions, let me know.
How Superheterodyne Works
th-cam.com/video/jQd2LfTOa4k/w-d-xo.html
Thanks Richard. I finally got some time to look at that video. I appreciste all your work over the years.@@AllAmericanFiveRadio
I am working on a similar AM radio and I am not sure if the first tube on the left is OK or not.
Basically I can find the adjustable tuning frequency of several MHZ on the grid but nothing comes out of the tube anode. The voltage is OK. Is that already a clear indication that the tube is damaged or could there be other problems (maybe on the antenna side )?
That's the oscillator mixer tube. If it is working there should be a negative voltage on the control grid. Whats the manufacture model of your radio.
Oscillator Trouble Shooting Using Radios as Testers Demo
th-cam.com/video/AuLP31cLBMQ/w-d-xo.html
Portable Tube Radio Repair, Troubleshoot Oscillator problem
th-cam.com/video/3PN92nLVqpo/w-d-xo.html
Thank you, thank you, thank you, for this fine explanation.
Van you do this also in a BX373a?
I have colored the section of each tube and labeled it's function. If you send me an email I'll send it to you, Make the subject Philips BX373A. allamericanfiveradio@yahoo.com
Really good explanations regarding the signal path and everything else within the radio. Thank you. Have subscribed. Just a beginner here trying to learn some radio basics. I have a question however, regarding the last part of the video (the Automatic gain control path via the R5). Why is it also tied to the Oscillator coil (B terminal) ? What does it do. ? Isn't that a somehow a typo on the drawing? Or. would that be a way to reduce the oscillators 455KHz level and in turn further reducing the overall amplification (in the event of a strong station ? Thank you.
R5 supplies the DCV stored by C8 for the ALC. It is common that a component has more than one function. C8 stores the ALC voltage, it isolates the OSC secondary from DC ground, and is the RF path for the OSC secondary to ground. I will do a video on this soon.
Here are a few videos you many find helpful.
How Superheterodyne Works
th-cam.com/video/jQd2LfTOa4k/w-d-xo.html
!923 Vacuum Tube, Amplitude Modulation Detector Circuit in Detail
th-cam.com/video/e0faax3Svgw/w-d-xo.html
MY FREE EBOOK
Password is allamericanfiveradio
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Brilliant! Many thanks from a novice.
Lynton
Thanks