The Stovebolt Site Forums The Shop Area The Electrical Bay The Radio Bench USA-630 Radio USB Issue

My better half bought me a USA-630 radio for Christmas to install in my '65 C10. Everything worked perfectly until I changed over to an HEI distributor. Now the USB will not work when the truck is cranked (everything else works perfectly). I took the radio out, call the manufacturer and told them the issue. They said to send it back. I did and they could find no issues with the radio or USB adapter. I hooked the radio up at the battery when I received it back and the USB worked perfectly (truck running). I thought GREAT. Well when I installed the radio back in the dash, it would do the same thing as before. With the ignition on, it works great. When I crank the truck...no go on the USB. I am thinking the HEI is interferring some way with the USB...in fact I know that is the case. Do they make any kind of shielding that I may could use the keep the radio circuits shielded from the HEI. The HEI distributor is right against the firewall (close to the radio). There was no problem with the USB with the points distributor. Any suggestions at all are welcome.

Leon -

I know you have the radio back in the dash - but how hard would it for you to be power the radio in the truck but not mounted in the dash. This to verify that its actually electromagnetic interference from the proximity of the radio to the distributor and not just a "noisy" power source when the ignition is on.

Just noticed your post in Electrical - and see that you've already determined its proximity to the HEI.

So you're looking fro EMI blocking I guess?

Yes, I have about come to the conclusion that it is HEI interference due to hooking the radio up at the batter and it works fine. Yes, I am looking for a way to lower this interference. I think it would not take that much shielding of some type to do it but have never really had to do this type of shielding before. I seen some different types on the internet but do not know the best kind to try. I hate not be be able to use this option on the radio.


Leon

There's already a firewall between the radio and the HEI correct? That's some pretty thick shielding already! Maybe you need some lead! Or paint the HEI in lead based paint!