Radio Problems
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Joined: Jan 2008
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From: Greenville Oh
Radio Problems
The original am/fm radio in my wife's 1976 has very low volume. You can only hear it if it's absolutely quiet and then it's just like a whisper. Is there any way I can test to see if it's the speakers, or radio, or both. Thanks
Team Owner
Joined: Jan 2006
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From: Crossville TN
Yes. Pull the right side dash panel, find the connector that sends signal to the right speaker, disconnect and temp wire it to a known-good 8 ohm speaker and fire it back up. If the sound isn't any louder, it's NOT the speaker. While you are in there, remove the convector (heat sink with the transistor...or 2 transistors, if it's an AM/FM/Stereo). That is the final amplifier stage and is likely the cause of your problem. Find someone to test the transistor; if it's bad, replace it with a suitable substitute. Those Delco type transistors are no longer made, but equivalent substitutions are.
Racer
Joined: Jan 2010
Posts: 402
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From: Medford NJ
I'm about to install the factory stereo in my '72 and I'm not sure it works (it came with the car recently). I thought that I recently read on the forum that the convector could be replaced with an amp. Is this true? If so, what wires from the radio would connect to the low level input of the amplifier? If its stereo, I assume that both factory convectors can be eliminated this way?
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Joined: Jan 2006
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From: Crossville TN
Well, I've purchased an amp and have not yet wired it up. {That old 'devil', Procrastination, got to me}. As soon as I've installed it, I'll report back to the Forum.
But here is some info I've been given: These old Delco units apparently have dc level voltage on the signal lines. Therefore, you have to put a blocking capacitor in the line(s) that feeds into the new amp. I have different sizes of capacitors that I'm going to try, till I find the right size that keeps the signal clean but doesn't cut out the bass frequencies. I'm sure this approach will work, but it needs some 'wringing out' to make it robust.
But here is some info I've been given: These old Delco units apparently have dc level voltage on the signal lines. Therefore, you have to put a blocking capacitor in the line(s) that feeds into the new amp. I have different sizes of capacitors that I'm going to try, till I find the right size that keeps the signal clean but doesn't cut out the bass frequencies. I'm sure this approach will work, but it needs some 'wringing out' to make it robust.
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Joined: Jan 2008
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From: Greenville Oh
Gave up on the old radio. Going to leave it in place and install a hidden stereo with remote control and a rear speaker system. Will have better sound and the wife can play her cd's and hook up her Ipod. This will make her happy, and the happier she is the happier I am. This will also mean I can put one of these stereos in my toy, a 1971 C10.
