Related Videos
The Audio Selection Panel allows you to control 4 Transceivers and hear the audio through the built-in loudspeaker and on an external boomset (combination Microphone/ headset).
On or more transceivers can be selected at a time to transmit and/ or receive. An additional receptacle can be used to attach a recording device or the PC soundcard. There is no separation of signal ground between the connected transceivers. This does not cause any problems in my set-up (only VHF/UHF transceiver), but your mileage may vary.
Like most of my circuits, this one is built on experimental "vero-board" and I have no intention of designing a Printed Circuit Board. I built this design with 4 channels, but you may use any number of channels, depending on your needs. The housing is that of a commercial desktop microphone, bought cheaply in the Dutch radio amateur museum ‘ Jan Corver’ in Budel. All connectors (Power supply, audio for 4 transceivers, boomset and the PC soundcard), are mounted on the rear panel of the desktop microphone. Audio and PTT signals are combined in 9 pin sub-D connectors to reduce costs. The boomset and power supply use standard connectors, but you are free to choose your own! The design is split into a number of separate function blocks, each built on a separate piece of circuit board.
Diodes D1..D4 isolate the PTT signals between the transceivers. Switches S6 (PTT Hold) en S5 (PTT Moment) are mounted on the front panel, as are switches S1..S4. S1..S4 are used to select one or more transceivers te transmit as switches S5, S6 or the boomset PTT button are pushed. The red LEDs D1..D4 (Tx1..Tx4) display PTT status per transceiver and are mounted just above S1..S4. Boomset PTT and Computer PTT (from the RS-232 port) are buffered by a Reed relay. All diodes are 1N4001 (General Porpose 1 Amp Silicon)
http://pe2er.nl/ASP/index.htm
