Icom 880 install in Toyota Corolla

[K8OCB]

I have an Icom 880 installed in my 04 Toyota Corolla. My car has a cassette deck, so I used a cassette deck adapter to listen to my MP3 player. I've had it and used it for many years - close to 8 now, and noticed that the sound quality is degrading over time.

When we installed my new rig, I simply plugged the adapter into the audio out on the radio - but the sound quality is terrible. I hear this high pitched whine - which I can only assume is the fan in the radio and it changes pitch (higher) as I step on the gas and brakes (goes lower when I hit the brake).

So I unplugged my adapter and am just using the radio's speaker -

Any idea what is causing this? Should I clean out the cassette deck? Get a new adapter? Has anyone ever tried this setup before?

[K0BG]

You didn't mention if your were using a mag mounted antenna. Based solely on the limited verbiage, I suspect you are, and the whine is from the alternator via a ground loop.

[KB4QAA]

Have tried cleaning and demagnetizing the tape deck head?

I suspect you are totally wrong and the problem is not audio quality, but ignition or alternator noise.

How is the problem with the engine shut off?
How is the problem with the engine running and the antenna disconnected?

-If the problem is really audio quality through the tape deck lashup, get an external mobile speaker and plug directly into the radio.

*Go check out Alan's website above.

[AK7OZ]

Just some thoughts. The average MP3 player output is roughly 60mW. I would assume that the CD players those cassette adapters were originally designed for would likely be roughly the same. I'm not familiar with that particular radio's specs, but most of 2m & 2m/70cm mobiles output a couple watts. I'm not so sure that cassette adapter could handle the additional power, especially one with considerable age/use. I would also assume that driving a couple watts of power into the stereo's pre-amp isn't really all too helpful either. I would think you'd have to drop the Icom's output wattage if you were going to use the stereo no matter which way you connect it. I'm about to install a new rig in my Subaru & the extra $40 for the external speaker seems to me to be a better deal than the headaches of a work around that may or may not end up in creating new problems in other areas.

The whine does sound like an ignition/alternator problem, but you also noted that you stopped using the adaptor & are back using the Icom's internal speaker. That makes me believe that there's another problem somewhere after the radio i.e. the adapter and/or the stereo.

Just my $0.02.