[CQ-Contest] Mixer

[Tom W8JI]

> Input is via mini phono plug or RCA connector.  There are two DC input
> connectors, ganged together to carry power to another accessory.  I wired
> audio and DC from the accessory outlet 1, pins 2,5 and 7, on the back of 
> the
> Icom 775.

There probably is the potential to drive 20 headsets with a single car 
stereo IC chip power amplifier.

If you use a fairly high power (compared to the power headsets need) audio 
source with low source impedance, you can bridge a half dozen headsets 
across the line without change.

Most radios fulfill this requirement on the speaker jacks.

Then a variable L pad can be used for volume, if needed, or even just a 500 
ohm pot.

73 Tom