[amsat-bb] Re: IC-910 Data Connections
Alan P. Biddle
APBIDDLE at UNITED.NET
Wed Jun 10 13:02:08 PDT 2009
There is a similar but not identical issue with my FT-847. I have used two
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.
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