Build a AF & RF Signal Tracer

[@audubon5425]

I need to rebuild the probe in my Eico signal tracer...I needed one today and remembered building this off this video when it first came out. Dug it out of a box from my old workshop and voila! Thanks again Richard for your books and videos.

[@AllAmericanFiveRadio]

Thank you, and your welcome.

[@MickLBrad]

My mentor, James R. Smith K4MPA-SK, showed me how to do this when I was a lad in the mid '50s. It was, and still is, an inexpensive means of getting I to radio repair. Thanks for sharing it, Rick. 73 -- de Mick, WB4LSS Bartlett, TN.

[@AllAmericanFiveRadio]

The black cable is connected to ground of the test radio. Yes. By reading the wiring diagram you can determent where the RF is/should be, and where AF is/should be.

[@AllAmericanFiveRadio]

When you need a signal tracer you really need one. A friend that works on radios brought one over that was giving him a fit. Everything checked out, all the coils, all the voltages, all the tubes are good and any other test I could think of. I used a tracer to find where the signal stopped. It was at the second I.F. can. We opened up the can and it was full of dust and dirt which shorted out the RF signal. After cleaning the insides of each I.F. the radio performed like new.

[@BadChizzle]

I like the way you pronounce things, it adds to the fun for me. If you went through every word in anyones vocabulary, you would find such variations from the norm here and there. I suspect even in the guy just before me in these comments. Rock on Rick!

[@AllAmericanFiveRadio]

Sure. I have been using O Scopes and signal generator since high school. I have built three O Scopes, and no telling how many other kits and home brew stuff. I have written two book on antique radio repair.

[@joernone]

Rick, This is pretty slick. Came along a little too late though. Had to finally break down and buy a Heathkit tracer. But I'm looking forward to seeing what else you have up your sleeve for this puppy. Regards, John

[@AllAmericanFiveRadio]

@dream501 It should work. If not Antique Electronic Supply has both diodes. And you do not have to drill holes in the cabinet, you put all that stuff in a small box and set it on top.

[@AllAmericanFiveRadio]

Thanks, I very much appreciate that. I'm studying the diagram for this unit to make it more useful as test gear, with as few changes as possible, but not making the changes unique to this radio. Rick

[@AllAmericanFiveRadio]

That sounds true. Most of the time if the stations are off the radio needs to be aligned. If it is an older radio you maybe able to find the information at nostalgiaairDOTorg

[@AllAmericanFiveRadio]

Thanks MickLBrad Sound like it is going to be a useful Mod. I hope some of the younger folks are helped by the videos, and get interested in electronics.

[@AllAmericanFiveRadio]

Thanks, and good luck with the Sparton 746-PA. Nice radio. I have put the FM stereo demultiplexer circuits in the KZbin video to do list file.

[@AllAmericanFiveRadio]

@TundraWalk3r Thanks Matt, If I made this today I would not drill holes in the cabinet. I would put everything into another box. There are a lot of these still out there, but don't drill holes in it. This is a very useful circuit and you can also detect FM signals. Rick

[@AllAmericanFiveRadio]

Hey John, I'm studying the wiring diagram now and my goal is to make more useful test equipment from different parts of this AM&FM radio. Rick

[@AllAmericanFiveRadio]

I think you will find it to be a very useful troubleshooting tool. And there's more information on the way.

[@AllAmericanFiveRadio]

Rocknrolldaddio I found a small error in the circuit diagram, so I redrew it and put a link to the new drawing in the 'Show more' of this video. Let me know if it does not answer you questions. Rick

[@AllAmericanFiveRadio]

That's great! Yes they are extremely useful in finding where the signal starts/stops and in finding noise. Thanks.

[@lovesavacuum]

Have watched several of your videos. They are very useful. I happen to be in the process of restoring a Sparton 746-PA console radio at the moment. I would love to see a similar video about tube based FM stereo demultiplexer circuits and how they work.

[@AllAmericanFiveRadio]

Hey Ron I'm planning on adding to its capabilities. I have a few ideas that should make this radio into a very useful piece of test equipment with multiple functions. Rick

[@kwacz]

I have a spare radio with a cracked bakelite cabinet with a few good size chunks missing out the bottom making the case worthless. I would have no problem making it with that radio, but I would hesitate to modify a good cabinet. maybe im just weird but i find it hard to do this to vintage stuff. I will definitely build this with my broken cabinet. I mean its already scrap and worthless.

[@AllAmericanFiveRadio]

You may like this idea. Build a Audio and RF Signal Tracer using a Guitar Amplifier kzbin.info/www/bejne/h4bQgXV4o9-eiKc

[@AllAmericanFiveRadio]

Yes I know and I was wondering how long it would take for someone to point that out. In this case it was one. I have three or more of them in the garage. This radio will be very valuable in 2883, lol!. Great about using the left channel for troubleshooting!!!! GREAT!

[@danielhaw7273]

The radio that you make the modification to, does it have to be AM/FM. Or can it be just an AM radio? Thanks for all you do.

[@toltec13]

Question: One end of the ground wire goes to the radio chasis, but does the other end go to? I'm puzzled.

[@wa4aos]

Hi, Have you had experience with doing a staggered IF alignment on a 455 KHz IF using an O Scope and sweep gen? This seems to be a lost art. Thanks, GLenn

[@AllAmericanFiveRadio]

Yes I have done videos on Transistor Tracers, go to my channel and do a Channel search on Tracer. Most of the time all you need is the tracer, and you can make that out of an audio amplifier.

[@walterabbott5347]

Will this same wiring diagram with same value components caps/diode work in a 9v mini solid state amplifier or would it have to be modified?

[@AllAmericanFiveRadio]

Sure, do a channel search on my channel for "tracer". you'll have at transistor signal tracer

[@kwacz]

can this be used on both tube and transistor radios for signal tracing problems??

[@AllAmericanFiveRadio]

YES Build a Audio and RF Signal Tracer using a Guitar Amplifier kzbin.info/www/bejne/h4bQgXV4o9-eiKc

[@ZmajSnoshaj]

What is it with Pink Floyd and Zenith ;)

[@762girl]

WONDERFUL! Freaking brilliant. I love this stuff!

[@harryshector]

Could you have had one set of banana jacks, and just used a SPDT switch to move from RF to audio, instead of moving the probe?

[@AllAmericanFiveRadio]

YES

[@AllAmericanFiveRadio]

Yes you could use a switch. Here is another design. Build a Audio and RF Signal Tracer using a Guitar Amplifier kzbin.info/www/bejne/h4bQgXV4o9-eiKc

[@LestonDr]

I have an FM Tube Regency Police Scanner I would like to convert to a guitar practice amplifier. Would I just follow your AF circuit and ignore the RF portion?

[@AllAmericanFiveRadio]

At the volume control is the start of the audio amplifier.

[@LestonDr]

Thank you

[@AllAmericanFiveRadio]

Build a Audio and RF Signal Tracer using a Guitar Amplifier kzbin.info/www/bejne/h4bQgXV4o9-eiKc

[@AllAmericanFiveRadio]

@trh847 If I was going to build this today I would put all the wires in another box, rather than drill holes in the radio cabinet. I did a video on the transistor signal tracer and it has a diagram of this circuit. It is the same circuit. I'll send it to you KZbin email.

[@AllAmericanFiveRadio]

Thanks 762girl

[@AllAmericanFiveRadio]

Rock Glad it was helpful. Rick

[@wolfgangbeginners-mind2853]

That's not am I'ts IGGY!!!!