Any Electrical Engineers out there?

[Klang]

Hi,

I want to tie the headphone-out of my GPS into the microphone-in of the comm. system on my '06 Ultra, and if that can't be done, into the amplified output that feeds the rider helmet speakers. I found all of the appropriate pins/wires, and I've made a test harness out of a headset cord.

I purchased a passive "mini mixer" that musicians use to combine inputs into one output, but it doesn't let the microphone work. When I try to drive the helmet speakers by mixing both radioi and GPS outut I loose too much volume. I don't want to install a "powered" mini-mixer - primarily because the outside of the barrel on the power source is positive on all models I see advertised, and I can forsee a horrible display of sparks and significant damage if it slips out of the plug and hits metal on the bike.

Anyone know the components I need to accomplish this mixing of microphone and line-out audio? I'd rather have the GPS drive the comm. system so the music "ducks out" when it delivers a turn instruction instead of mixing with the amplified output directly to the helmet speakers, but I'll take what I can get.

Thanks.

[mlewis]

I suspect what you’re dealing with is trying to couple a low impedance output source (GPS output) to a high impedance mic input, but I’m not sure that’s the case for motorcycle intercoms. There are audio matching transformers (high to low impedance) available at most electronic supply outlets that might improve you’re chances of getting this to work, but I think it will still reduce you’re mic level some in doing so. An alternative solution that might work just as well would be to mount a miniature speaker (driven by the GPS) next to your intercom mic. Those inexpensive earplug style headsets for iPODs would make for a good miniature speaker source.