Any ideas on how to get rid of engine noise in radio? I installed a USA1, put filter between radio & amp, didn't work. I tried the filter between the 2 hot wire connector at alternator, no help. I am wired directly to the battery except of course the power wire. HELP!! ANY IDEAS WOULD BE APPRECIATED. TERRY

You have to determine the cause of the noise first, not just start installing filters everywhere. Make sure it's well grounded. If the noise or whine matches the engine rpm's, it's probably the alternator. There are filters specific to the alternator to use. Most of the restoration houses carry them. It could be a general ignition noise...make sure your shileding is in place around the distributor, coil and plug wires. If you have a big block, the spark plug wires the factory installed are individually wrapped and shielded in stainless steel weave.

There are filters that can be installed directly on the radio itself. There is also the possibility the radio itself can be faulty and was manufactured with insufficient filtering. Corvettes, being fiberglass, are prone to radio interference problems since the fiberglass has no RF shielding ability, thus the need for the factory shielding around the ignition under the hood.

Also make sure your speakers are wired in phase...the + wires from the stereo to the + terminals on the speakers and - to -. If not in phase, sound quality will suffer.

If nothing else, visit a professional car stereo installer. They should be able to help.Gunslinger38471.3749537037

My understanding is that the firewall in our vettes is fiberglass instead of steel, so you must have the distributor shielded in order to eliminate that source of interference.  I believe all vettes came with such a shield that covers the entire back (firewall side) of the distributor and the top of it.  If you no longer have that, I'd look into that first.

USA 1, is that the brand of radio? Can't say I've ever heard of that make. My '79 had the original am/fm/8track in it when I bought it, and no ignition shielding at all, with a hei distributor. Then I installed an Aiwa am/fm/cd player and a xm satellite radio system in it. The ignition system was upgraded to a MSD distributor, Holley cd box and coil, still with no shielding or filters. No noise what so ever except awsome tunes. Now, I don't even carry cd's in the car, just listen to TopTracks on XM, classic rock. 100+ channels to listen to and most are commercial and dj free. I'm thunkin it may be the radio.

Dave

Pumps38471.4326273148

Terry,   I too installed the USA 1 in my car just a few months back. To answer Dave's question, it's the "custom autosound" brand carried by corvette America and most of your mail orders!! Anyway, I believe in this case you get what you paid for and the USA1 is the "most economical" brand available!

I do have the distributor and wire shielding that Gunslinger mentioned. I DO NOT get any radio interfearence, and I haven't installed any aftermarket filters. Lousy reception, yes, but no static noise!

I hope that helps a little..   Good luck...
PS: I use the tape drive more than the radio   

Steve

As usual you guys make perfect sense. When you drive a plastic car, you have a lot of anteneas. The noise is definatly from the alt. I will look into a filter, & let you know. As far as shielding, their is none. I have the plug shield but not the dist. I am running stock dist. with MSD cap & blaster coil. The p wires are accell 8.8 non shielded. I am really not hurting for sound, I can sit behind the wheel & listen to her purr all day. THANKS GUYS. We"ll figure this out Terry
PS Steve I had to look in the garage to see if my car was still there. NICE RIDE

ditto!

the usa-1 is a custom autosound unit, right? do you like the
quality of it besides that electrical hum? theres alot of mixed
opinions on that brand.

 When I bought my car back in 93 it had a Claireon radio in it. It sounded good but the tape player quit working so I bought the USA-1. The noise you are asking about started with that. I never could get rid of it. The tape player fell apart and I had to send it back to them to get it fixed. They charged me over $50 and when I got it back it still didn't work right. I had to keep playing with it to get a tape to work. I never could listen to any AM stations (sports) because the alternator wine was terable. I had all the covers on the plug wires. Long story short- I just put in a Pioneer CD/radio (DIN) and it is a hell of a lot better. Just a slight alternator wine with AM stations but nowhere near as bad.

Steve, you are correct, it's the botom end (about $165.00) of the USA - auto sound line. It is as the price indicates.. a very CHEAP radio... It took a lot of work to get the knobs fit right, the radio itself fit without any problem. The quality of the sound, lets just say I'd rather listen to my exhaust   

As in life, you get what you pay for.. I must say my tape deck works pretty well, as long as I carry a screwdriver to unwedge the cassette tape.

What strikes me is that all the mail order shops seem to carry them... I do know they have models all the way up to a USA - 6, but if I'm going put that kind of money into a stereo, I'd do what Brian did and get me a good pioneer...