Learned something interesting about 1st gen audio today.

[MiCarl]

I'm replacing the cassette deck on my 89 with a hook up for an MP3 player.

 

I put a switch on to enable/disable the radio. I was wondering what the effect would be if the radio was on AND I had audio feeding from the MP3. Turns out it behaves just like the intercom - when there is audio from the MP3 it mutes the radio.

 

This would be annoying with an MP3 because the radio would be piping up at quiet sections and between songs. It would be a really slick way to tie in something like GPS or cell phone though. Of course the radio would have to be on to hear the other device.