72 Radio Problem

[Mike Carter]

I've got issues with my 72, had Kenwood aftermarket in it that lost volume, couldn't hear it. Also balance was messed up. I put original AM/FM in it (rebuilt). Sometimes loud, sometimes no volume. Pops loud when switched from AM/FM. Has power/ground and light. Pulling my hair out. Thought it has to be radio, but two radios same thing. Kenwood did work at one time. Appreciate any suggections.

 

[69MyWay]

You have a ground wire....but how good is the ground connection?

 

[Mike Carter]

Rings with meter, I'll check for good connection.

 

[Mike Carter]

How important is the 10 Ohm speaker, the car has aftermarket polarized in it?

 

[MidShark]

Mike
I'm not sure on this, but I was always under the assumption that with the factory radio, you have to use the factory amplifier with it. Are you running that between the radio and the speakers?
Dick

 

[Ala75Vette]

....I would also bear in mind that the original Delco radios were 3W (yes, that's 'three watts') systems, and the speakers used with them were 3W speakers. A friend of mine has a '71 which he restored to original, numbers matching, and had to yank the aftermarket speakers in it and replace them with 3W ones to work with his original radio.

 

[Mike Carter]

thanks, I have the amp (stock) and it is installed, I agree with the aftermarket speaker piece, that is next step to replace speakers, didn't realize 3W, but makes sense.

 

[tonyk72]

I've had my factory stereo outta my '72 for over 2 months now...previous owner had aftermarket speakers (4ohm I think)wired up to the factory radio...He told me that after a while the radio just stopped working.
I took the radio to my dad-in-law whos an electronics repair guy and he found nothing wrong with the stereo or the amp.
So I removed the aftermarket speakers, plugged everything back to the correct (10 ohm) speakers and still no luck.
I tested the voltage coming into the stereo and I got 14.2V.
He told me that I most likely have a poor ground somewhere...I'm not very good with electricity, but I assume since I'm getting the voltage....the ground must be OK too...right?
I'll be messing around with it again this weekend.
I sent the stereo back to him to have him double-check it...
I'll let you know what I find...

 

[Mike Carter]

Tonyk72,

I'd appreciate feedback, I'm working on this one too, I'll keep you informed, everything ohms and measures right. I'm going to replace speakers, and I have another stock radio, this is weird, and I'm an electronic guy, Weird.

 

[tonyk72]

I spoke to my dad-in-law today. He's coming over this weekend to help me install...he double checked the stereo and he said everything checkes out...I'll see what happens...

 

[Nut]

Tony... when I had my '72 years ago I had yearly issues with the amp. Finally had it gutted and rebuilt with upgraded components. Never gave me a lick of trouble after that. But most every problem ended up being amp related. Also the 3ohm speakers are mandatory with the original radio. Good luck.

........... Nut

 

[Mike Carter]

Thanks Nut, appreciate the advice.

 

[Mike Carter]

tony,

One word, speakers. I hooked up a set of dash speakers I have and it worked, my 72 has one transistor amp it works. appreciate all the good advice I got, and it's working.

 

[tonyk72]

lucky you! I had my dad-in-law come over today to see if he could get it working...no luck. We hooked up another stereo and it seemed to get power, but when we hooked up the original radio, for some reason there is a loss of power. He took it back home to take a 3rd look at it, he thinks he has narrowed the problem down...
Speakers were tested OK (10 ohm), factory originals
So Mike, your original problem was due to the atermarket Kenwood speakers?
Nut, you sure about the 3ohm rating?
the radio does light up...
he's gonna try to run the radio off a battery to simulate the actual power it would get in the car...
when he runs it on the bench hooked up to one of his power generator thingamagigs..it does test OK
wierd
If we can't get it working on the 4th attempt, I'll be forced to install some 100watt MP3 player in its place...life sucks huh?

 

[Mike Carter]

Tony,

Yep, my problem was speakers. I now have two stock radios and I'm not taking the drivers side dash apart, ordered two kick panels tonight. My advice if it's a daily driver, buy the upgrade, not worth the hassle to be original unless it is all original car.

BTW - I use one of those Sears power packs, made a cig plug with clips that I can bench test all 12V stuff before installation makes my life simpler.

know anyone who needs a stock radio and two dash speakers let me know.

Wish you the best.

Mike

 

[tonyk72]

I'm done!

After almost 6 months with the dash apart waiting for the stereo, breaking the bezel, sending the radio back 3x, seeing it work on the bench test...it's in & it works! I always suspected the aftermarket alarm had something to do with my problems...but I was wrong. On my way to the uninstallers, I decided to try the radio one more time...and bingo! It worked! I have no idea what could have been wrong. I was told the stereo was in fine working order every time I brought it back (glad my dad-in-law is patient). He did replace a few components anyways...

 

[resto75]

Ah don't you just love when something baffling just fixes itself. Now if it only stays fixed your in business.

 

[Mike Carter]

Cool,

I gave up and put aftermarket in mine, admire your patience.

Mike