1967 Radio Reception

[Salvatore I.]

OK, ok, I know it is 37 years old, but when I turn it on, I expect to hear some music!

Radio gets moderate to poor reception. Replaced 3 ground straps, one at the antenna, one at the LH body sill and another at the accelerator lever...radio has only slightly improved. Antenna body, housing and ground plate all relatively new. Noticed that the cable has a small nick in it near the ground strap.

Reception improves and then fades...any advice?

[Joe R.]

Re: 1967 Radio Reception

Sal,

Unfortunately for you, 100 extra ground straps will not help your radio with better reception. Check to see that you antenna is plugged in the back of the radio and the antenna. If it is OK, send it to a radio repairman. Several recommendations in earlier threads.

Regards,

JR

[Salvatore I.]

Re: 1967 Radio Reception

JR

Can I get to the back of the radio by taking the driver side panel off?

Do you think the cable is the culprit?

Sal

[Joe R.]

Re: 1967 Radio Reception

Sal,

Probably easier from the passenger side cover. No, I don't think this is what is wrong with your radio. Me thinks it should be in the repair shop, but what do I know. It could be the antenna, speaker or just and old tired 37 year old radio. Most likely the later, but good luck.

Regards,

JR

[Rob Dame]

Re: 1967 Radio Reception

There should be a antenna trimmer adjustment.Make sure the antenna is up all the way. Tune the radio to the weakest am station between 800 and 1100.
You'll see a small hole usually near where the antenna plugs into the radio.
In that hole will be a small slotted screw. With a small screwdriver and the radio on a weak station turn the trimmer adjustment till you get the strongest signal.

It's worth a shot.

Rob

[Dick W.]

Re: 1967 Radio Reception

Trim will improve AM reception only. The only thing that you can do for FM is to fully extend your antenna

[Salvatore I.]

Re: 1967 Radio Reception

Thanks, Rob

I will do as you suggest. Per subsequent posts from Dick and others, it seems like this will help with AM reception which is better than what I have now.

Others have emailed me to suggest that the antenna be tested using a cheap substitute and if the reception improves dramatically, the culprit is the cable. This sounds like a logical and thoughtful next step and for $7, it is worth testing.

If that's not it, then it is off to the radio shop!

[Jack H.]

IF you go the route of radio repair...

here are a couple of tips. First, the network of independent AC-Delco/United Delco dealers GM tooled are still out there across the country. A number specialized in radio repair and have the GM manuals, training, and a limited stache of older radio parts. If there happens to be one in your neck of the woods, this will typically be faster/cheaper than sending the radio out + some of these shops will do turn-key work if you drop the car off.

Second, if the radio has to go out (to anyone) it's reasonably important you send it AND the speaker together.... The early (pre-68) Corvette radios were unique. They mounted the DS-501 speaker drive transistor's matching transformer on the speaker vs. installing it inside the radio chassis as other Chevy cars/trucks with more space behind the dashboard did.

If the speaker lacks a proper matching transformer (actually only one side of the transformer is used to effectively make a large flyback inductor) or the transformer is damaged, you can wind up with low audio volume that's also heat sensitive (symptoms look like poor reception). A bench tech can't diagnose properly without both components (radio and speaker).