Help with KMA20

[Cliff]

I have a KMA20 installed with 2 KX175B's. Where do I set the AUTO,COM1,COM2
toggle and rocker switches? I do have a 4P intercom and speakers. I would
like to set COM1 as primary and COM2 on 121.5 for monitor.

Thanks
Cliff

[Brian Cox]

"Cliff" > wrote in message >...
> I have a KMA20 installed with 2 KX175B's. Where do I set the AUTO,COM1,COM2
> toggle and rocker switches? I do have a 4P intercom and speakers. I would
> like to set COM1 as primary and COM2 on 121.5 for monitor.
>
> Thanks
> Cliff

Hi Cliff,
The toggle/rocker switches control which radios you listen to. The
circular selector knob controls which radios you use for transmit.
Let's take them one at a time.

If you want to transmit on the radio that is wired as #1, then turn
the selector knob to COM1. Select COM2 to transmit over the #1 radio.

For receive, there is a selector for COM1, COM2, NAV1, NAV2, ADF, etc.
The toggle switches typically have three positions. You can turn
them ON or OFF. If you select AUTO, then you will be listening on the
same radio that is selected for transmit.

Therefore, if you set both COM1 and COM2 for AUTO, then tune two
frequencies in the two radios, you can switch back and forth by using
the transmit select knob.

If you want to be on tower frequency, and also listen to ATIS, tune
TWR frequency in #1, select COM1 for transmit, and set COM1 for AUTO.
Tune the #2 radio for ATIS frequency, and use the toggle switch on
COM2 for ON. You will hear both ATIS broadcast, and also be able to
listen to tower frequency. When you key the mic to talk, you are
transmitting on Tower frequency.

Similarly, if you want to stay on frequency, but also listen to
confirm the identification of a Navaid, then do the same as described
above. Instead of selecting the COM2 toggle on to monitor, instead
select the NAV1, NAV2, ADF, etc. toggle on to listen to it.

Hope this helps. Probably most trainer aircraft are missing the
operating manual for the radios, and folks end up getting a verbal
briefing on how to use it, or have to rely on intuition and experience
with other equipment.

Safe flying,
Brian