vetter61

Have a 67 vet with very poor FM radio reception. Seeks like I just can't quite lock on to stations. Anyone know of any ideas or solutions?

Bluestripe67

You can have it converted internally for improved reception. The people who can do this are listed here on the forum. Search under "radio conversion". Dennis

70mph@2200rpm

I recently had my radio upgraded to the current technology, including an iPod jack. Although I'm pleased with the results, disappointlngly, my FM reception seems to be no better. The stock GM radio in my 2005 Astro Van continues to have a little better reception than my vette radio, before or after conversion.
I have a power antennae so I can't/won't make any improvements with that.

66jack

Did you fine tune it?

I cannot remember what side its on, but probably the channel finder side, there is a small "paper clip size hole" used to adjust.

Find a faint station and fine tune it through the hole...i think a SMALL SCREWDRIVER is used.

DansYellow66

A long forgotten about, standard adjustment that became unnecessary on radios somewhere about 30 years ago when digital tuning became common place. I think you have to pull the **** and tuner ring behind it both off to find it.

70mph@2200rpm

Really? that sounds way too easy...haha
thanks!

Mike67nv

You have to remember, the technology that went into midyear Corvette radios is 50 years old. Even when new, they weren’t comparable to today’s radios. Your antenna and cable may be contributing to your problem but most likely, radio components, like the germanium transistors, need replacing.

Repair shops, like Jerry Rudbeck at ElectroDesign (http://www.electrodesign.us/), can get your radio back to like new condition, but the performance will never be like a modern day radio.

The antenna trimmer screw mentioned above is for AM reception, no affect on FM.

DansYellow66

Opps - yes, not much good on FM. Overlooked that.

67vetteal

Jerry is the best!

Aussi-66

The screw adjustment being discussed is the AM antenna trimmer it has great effect on AM performance particularly at the the top end of the AM band. To ajust this trimmer tune the radio to a weak AM station above 1500khz and adjust the screw behind and to the side of the tuning **** for maximum volume. The comment that these radios are using technology that is 50+ years old is right on. The PNP gemanium transisters used in these radios had poor VHF/FM band performance.
I recently rebuilt my radio, I replaced all the electrolytic and the FM RF amplifier transistor with a high performance PNP silicon type followed by a full re alignment. The result is a radio with much improved FM performance the AM is unchanged but very adequate.

C2Driver

I pulled my radio out back in 1990 for a rebuild and there is a Delco adhesive label on mine that reads "FM reception only within 18 miles of transmitter", or words to that effect. After the rebuild, I could pull in some reasonably distant FM stations.

70mph@2200rpm

I emailed Gary Tayman who converted my radio. I asked him about the FM component of his conversion, as I wasn't sure if the FM parts were also upgraded, and here is his reply.

"With a conversion, all of the components are removed and replaced with a modern PCB, which includes a new digital tuner. Reception, even when testing these on the bench, is very good – far better than the original radio could have ever hoped for. If you are not getting decent reception in the car, your first step is to check the antenna. Quite often bad lead-in wires or bad grounds can result in less-than-satisfactory reception".

Frankie the Fink

You have to realize that the steel parts of your car are important parts of your antenna. The antenna should be grounded somewhere close to the mast and not just at the radio.
My C1 has a separate braided wire for that purpose right in the trunk. The chassis is the 'ground plane' for the antenna. Check yours.

toddalin

You can try an "antenna booster." My aftermarket power antenna has a relatively short mast and came with a booster for use in weak areas. At first I left it off and couldn't get reception here in the hills and it was poor in the flatlands.

I finally put it on and the difference is like night and day.

It now "outpulls" my late model cars here in the hills and cleaned up the signal considerably.

This is using a "stock" '64 radio that drives an aftermarket 4-channel JBL power amp, rather than its own power amp. The power switch was also modified to bring up the antenna and turn on the power amp.

70mph@2200rpm

I'm going to check ground at the antenna. Meanwhile, what booster mfg. did you install, and where did you install it?
thanks

toddalin

It was included with the antenna (don't remember the make) and installs between the antennna cable and back of the radio.

70mph@2200rpm

thanks for the reply.
With the Vintage air ducts behind the radio it was difficult enough installing the radio unit after it's conversion. I suppose the new booster can be spliced in anywhere between the antenna and radio?

Pilot Dan

The antenna cable itself is an often overlooked part of the wiring system. They are equally prone to corrosion from the inside out as the rest of the wiring harness is. Also, the antenna has a grounding plate (or is supposed to have one) on the underside of the body. Check that and the ground wire that goes from there directly to the frame. Pilot Dan

Aussi-66

Using an external FM antenna amplifier is a very practical solution, the problem with these old radios is the poor performance of their FM/RF amplifier. Adding external RF gain is a good solution that is best applied as close to the antenna as possible. There is an antenna connector located in the rear drivers side corner of the trunk. There are inline 12 volt RF amplifiers avialable on the web for about 10 bucks. Just insert the amplifier in the rear corner of the trunk and the old radio will come to life. When you install an inline FM amplifier it is a good idea to reajust the AM antenna trimmer located behind the tuning ****.

70mph@2200rpm

Is this the item you are suggesting?

http://www.ebay.com/itm/12v-Car-Ante...-/220873703748