[amsat-bb] Re: IC-910 Data Connections

[Alan P. Biddle]

Jim,

There is a similar but not identical issue with my FT-847.  I have used two
different approaches.  

I used to run the leads, mostly in parallel except for the 1200 and 9600
baud outputs, to radio ports 1 and 2 on the DSP-2232.  Switching the modem
loaded automatically switched the inputs and outputs.

Since I started using sound card programs several years ago, I made up a
simple ABC switch.  DIN cables, jacks, boxes, and wafer switches are cheap
at a good hamfest, and not that expensive at parts stores.  Another trick
for a selector, which I saw documented in QST, is to use a serial AB or ABED
box which are cheap, and nearly free at a hamfest flea market.  You can make
up adapters, or install DIN sockets.  All the wiring is at audio frequencies
and is uncritical.  A metal box for shielding is recommended!

Note that however you do it, the audio levels from the DSP-2232 are not
constant when you change the modems.  If you use the same radio port, you
will need to provide some sort of means of equalization.  I used some cheap
trim pots in my switching box.  If you use separate radio ports, you can set
them individually using the DSP-2232 level controls.

Alan
WA4SCA