FM Discriminator Circuit Audio Detection

[@knifeswitch5973]

Rick, as always you have a gift for breaking down these circuits so even the dullest knife in the drawer (me) can understand it’s workings. Thankyou sir

[@AllAmericanFiveRadio]

LOL! Thank you, and your welcome.

[@thomasknapp7807]

The video was extremely informative. The combination of the early oscilloscope demonstration of effects and the later schematic representations helped me build 3 LTSpice models which show the LPF characteristic of the Pi Network, the high Q of the double tuned IF Can, and finally the full FM discriminator circuit. In the model, when an FM signal with a 3 kHz modulation drives the IF Can, the 3 kHz signal is displayed at the audio port. An FFT of the audio port shows the 3 kHz signal and the 10.7 MHz IF carrier. I will send the LTSpice models to AllAmericanFiveRadio, if you wish.

[@AllAmericanFiveRadio]

I’m glad my videos has helped. Your comment is very much appreciated and I hope you continue to experiment with circuits. The more you learn the more fun it is. Thank again, Rick.

[@LousyPainter]

Excellent! There has always been something missing in my umderstanding of this circuit. I get it now! Thank you for all that you do my friend.

[@AllAmericanFiveRadio]

Glad this video filled in some missing peaces. Thank you, and your welcome.

[@brucebuckeye]

Yes, I was in the same boat! I get it now!

[@Theoobovril]

I do very much enjoy your instructional videos, Rick, well appreciated by many-many viewers here.

[@AllAmericanFiveRadio]

Than you, thank you.

[@brucebuckeye]

Thank you sir! I was able to follow what you said and I learned something new! Thanks for taking the time to carefully show and explain!

[@AllAmericanFiveRadio]

Thank you, and your welcome.

[@jp040759]

Great explanation Rick. Thanx for clearing that up. Ingenious!!

[@AllAmericanFiveRadio]

Thank you, and your welcome.

[@Radio478]

Very good video, I learn much from it, thank you from England

[@AllAmericanFiveRadio]

Thank you, and your welcome.

[@TonyButchT]

Thank you for this explanation! Does the signal lose strength (voltage) when it exits/leaves resonance?

[@AllAmericanFiveRadio]

Thanks. Yes the level decreases off resonance.

[@dinkc64]

Well thank you very much for making this great explanation of the discriminator circuit.

[@AllAmericanFiveRadio]

Thank you, and your welcome.

[@rewalton46]

That was an excellent explanation! I think I understand the discriminator for the first time. Can you do a similar explanation of the ratio detector?

[@AllAmericanFiveRadio]

Thanks you! Good idea!

[@AllAmericanFiveRadio]

Do you have a manufacturer and model number of a radio?

[@DavidSmith-zx7wz]

Beautiful explanation! Thanks for what you do!

[@AllAmericanFiveRadio]

Thank you, and your welcome.

[@bobdoritique7347]

Merci, for this video. Is it an Foster-Seeley schematic please?

[@AllAmericanFiveRadio]

It is from MOST-OFTEN-NEEDED 1965 RADIO SERVICING INFORMATION Radiomuseum.org: M722L Ch=6M06

[@tectalabyss]

Thank you Rick. I love to see how these circuits work. Liked and sahred. All my very best.

[@AllAmericanFiveRadio]

Thank you, and your welcome.

[@MrTechHistory]

Could you please do the same within with stereo FM and take us through beginning with the IF. Thank you.

[@AllAmericanFiveRadio]

Thank you! Good idea!

[@andrewferg8737]

My Christmas present arrived a bit late, but it was just what I had asked for... Thanks!

[@AllAmericanFiveRadio]

Thank you, and your welcome.

[@andrewferg8737]

@@AllAmericanFiveRadio Question: I wish to avoid the frequency to amplitude conversion until my signal is appropriately amplified and filtered. As this requires a number of IF stages, how do avoid losing my audio information in process? It seems to me that initial IF transformer would prematurely turn my FM into AM and then lose information in the second or final IF transformer. Am I mistaken?

[@AllAmericanFiveRadio]

@@andrewferg8737 You might investigate using Phase Lock Loop and crystal filters. Something else to look into are the new Ham radios, like the IC-7300. This is from ICOM… RF Direct Sampling System The IC-7300 employs an RF direct sampling system. RF signals are directly converted to digital data and processed in the FPGA (Field-Programmable Gate Array), making it possible to simplify the circuit construction. This system is a leading technology making an epoch in amateur radio.

[@ericklassen742]

As usual, I'm enjoying your video. In your download e-book, you mention testing th oscillator by using a scope. There, you mention pin 3 on the 6sa7 as the testpoint. Where do I connect the black lead? Do I go to B-? I don't want to damage my ne scope. Thanks

[@AllAmericanFiveRadio]

The black lead goes to ground. If you do not have an isolation transformer, I would put a 0.01 at 630WVDC capacitor between the black lead and ground.

[@buddyhoover57]

Why did the demonstration show the use of a 455khz IF transformer?

[@AllAmericanFiveRadio]

Because I don't have a 10.7MHz

[@TheGmr140]

Nice video on fm demod 😊😊

[@AllAmericanFiveRadio]

Thank you and your welcome.

[@suhailasaba1051]

Thank you for referring me to this good video.

[@AllAmericanFiveRadio]

Thank you, and your welcome.

[@romjone4801]

Rick, how can I download the ebooks? All I saw was the videos.

[@AllAmericanFiveRadio]

The information is in the SHOW MORE or in the ABOUT on my channel. Hope you enjoy the book and find it useful. Here is the password ad link: Password is allamericanfiveradio kzbin.info?event=channel_description&redir_token=QUFFLUhqa2hhVTRycWdJd1FUbTFCZWNmdGtQNlZCRmEzd3xBQ3Jtc0tuOFQ2bFhRcWdjdUdIcUREcnZFaHc0M2xURGhITVRuWDE2cGlDakdYUF9uODktNzc3TVRJTWdROUt6R3NLN2lla3hFS2lIM0RnOXR1dXFxMGx2cUNtWDhXb1Zvc2RCbGQxTThoendmN2E5R0lJdmI0Yw&q=https%3A%2F%2Fdrive.google.com%2Ffile%2Fd%2F1HHmaWYr7UMACfmS4W5uL6PADoem2KlRp%2Fview%3Fusp%3Dsharing

[@Dr.acai.jr.]

Do you mind me asking how many years experience with electronics you have? Your channel appears to be another Mr Carlson's Lab - a wonderful find if it is. A search for someone talking about the NEETS manuals turned you up. So, if you don't mind - purely out of curiosity - how many years?

[@AllAmericanFiveRadio]

65+

[@Dr.acai.jr.]

Great news. Thank you. @@AllAmericanFiveRadio

[@DriveInFreak]

Is that the Armstrong circuit?

[@AllAmericanFiveRadio]

Zenith did pay Royalties to Armstrong.

[@happydog4929]

BRAIN CANDY. thanks

[@AllAmericanFiveRadio]

Thank you, and your welcome.

[@adhamali117]

السلام عليكم هل هناك فيديو او رسم توضيحي لدئره البلازما بيتر ليندمان

[@AllAmericanFiveRadio]

The wiring diagram is at 7:18 in this video. This is a link to the FM Transmitter. FM Transmitter Home made Coil Build Demo kzbin.info/www/bejne/f6qbg6KiZtOMY6s

[@Pilotfly2023]

Thks, Sir.!

[@AllAmericanFiveRadio]

Thank you, and your welcome.

[@bob_mosavo]

Thanks 👍

[@AllAmericanFiveRadio]

Thank you, and your welcome.

[@rob_scooter6199]

thank you

[@AllAmericanFiveRadio]

Thank you, and your welcome.