I listen to music, GPS directions and make phone calls on the road in my HMMWV through the intercom headset.
They also work on the VIC-1 but the functionality is a bit more limited (see notes below).
Due to popular demand I did a test run of 20 units and sold them over on SteelSoldiers. I’m planning a second run of 20 if anyone here on G503 is interested.
They are plug-and-play, with a standard 18-pin audio connector for interface with the VIC system and a standard TRRS headphone jack for interface with the phone. You must supply the intercom cable (CX-13473 or CX-13489 for VIC-3, CX-4723 for VIC-1).
The design is a professional job with a mix of surface mount and through hole components on a custom manufactured PCB. It’s mounted in an IP67 rated enclosure. They are hand-made by me in California.
Price is $100 each + $15 shipping CONUS.
I have tested these with both VIC-3 and VIC-1 systems and have some important notes:
VIC-3: Plug and play. Connect the phone box to one of the radio ports and you are done.
VIC-1: A bit more complicated unfortunately. Because of the way the VIC-1 is designed, if you want to make outgoing calls on the cellphone, the phone box must be connected to J501 (Radio A) and the crew box must be set to "ALL". This also means that DC power must be supplied at J508, and the "Installation" switch (which is set with a flat head screwdriver) must be set to "INT ONLY". The main power switch must also be set to "INT ONLY".
If you don't care about outgoing calls and only want to listen to music, GPS directions, etc. (receive only), then you can connect the phone box to J503 (Radio C). The crew boxes must still be set to "ALL" to hear the audio from the phone. If you switch the crew box to "Radio C" you will be able to transmit out the phone, but you will not be able to hear the audio coming back.
The reason you can only hear audio in the "ALL" position is because at the "ALL" position, the line level audio from all connected radios is mixed and amplified by an internal amplifier within the AM-1780. In any of the individual "A", "B" or "C" positions, the audio supplied from the radio is expected to be amplified already and the phone output isn't powerful enough to be heard.
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