lostforawhile
12-27-2009, 12:11 AM
Well I've been trying to figure out how to make one FM modulator work for two inputs, and I didn't want to install a bulky manual switch box, So I finally came up with this idea, I had a nice heavy duty 4p DT relay from a welder in my junk, it was 24 volts so i hadn't even considered it, I was messing around with it, and the thing will operate just fine on 12 volts dc. I used it, some shielded wire I already had, took a set of audio jacks out of a dead equalizer, and all i needed was a box, I was trying to figure out where to find one, then I remembered I have about a hundred obsolete airplane strobe drivers, they come in a nice shielded aluminum box. So i gutted one , transferred the hole pattern over to it, and drilled all the holes for the jacks.
this is what I ended up with, the cover isn't on it yet. I'm running a Rosen wired modulator, i have this set up so the MP3 player is the default input, when the XM radio is turned on, it energizes the relay, and the input is switched to it. It won't have perfect sound being a modulator, but I just want it to be loud mostly. The sound will still be a lot better then an over the air one.
what the audio jacks came from, just unsoldered them
http://i220.photobucket.com/albums/dd158/lostforawhile/S4020783.jpg
the side of the case where the phone jacks stick out
http://i220.photobucket.com/albums/dd158/lostforawhile/S4020784.jpg
one of the jacks unsoldered with the relay
http://i220.photobucket.com/albums/dd158/lostforawhile/S4020785.jpg
going together
http://i220.photobucket.com/albums/dd158/lostforawhile/S4020788.jpg
how it fits in case,with top off
http://i220.photobucket.com/albums/dd158/lostforawhile/S4020792.jpg
FM modulator
http://i220.photobucket.com/albums/dd158/lostforawhile/S4020791.jpg
this is what I ended up with, the cover isn't on it yet. I'm running a Rosen wired modulator, i have this set up so the MP3 player is the default input, when the XM radio is turned on, it energizes the relay, and the input is switched to it. It won't have perfect sound being a modulator, but I just want it to be loud mostly. The sound will still be a lot better then an over the air one.
what the audio jacks came from, just unsoldered them
http://i220.photobucket.com/albums/dd158/lostforawhile/S4020783.jpg
the side of the case where the phone jacks stick out
http://i220.photobucket.com/albums/dd158/lostforawhile/S4020784.jpg
one of the jacks unsoldered with the relay
http://i220.photobucket.com/albums/dd158/lostforawhile/S4020785.jpg
going together
http://i220.photobucket.com/albums/dd158/lostforawhile/S4020788.jpg
how it fits in case,with top off
http://i220.photobucket.com/albums/dd158/lostforawhile/S4020792.jpg
FM modulator
http://i220.photobucket.com/albums/dd158/lostforawhile/S4020791.jpg