[Trent772]

We have one of these as our box 2 and could do with upgrading to 8.33.

Does anyone know of a direct slide in replacement for this that is more economical than buying a TSO'd Bendix King 8.33 radio ?

The original was only $1000........

[Cookie]

Icom IC-A220T with MBA-3 adaptor.

https://www.gps.co.uk/icom-ic-a220t-vhf ... /p-0-1954/

Cookie

[MikeW]

If your system includes a Sigtronics intercom (or some other less common ones) the ICOM will not transmit unless you incorporate an extra relay. I know a couple of people who had this problem.
It is explained and the solution given on the Sigtronics website.

https://www.sigtronics.com/_pdf/air_pdf ... ne_Mod.pdf

[CloudHound]

My ICOM IC-220T has an excellent built in intercom.

Unless the Sigtronic does another important function I'd omit it.

[MikeW]

That is of course a workable solution, but if the intercom is already there it is easier to leave it connected (and filling a hole in the panel) than rewire the system. Also many (me included) find it easier to have knobs for the I/com volume and squelch than dive into sub menus on another device. (I don't know how accessible those settings are on the ICOM, I have a Dittel.)
James kept his I/com when he got an ICOM, Steve who fitted it showed me how he added the relay very neatly.

To clarify, adding the relay to the wiring is very simple. Where the guys I know had problems was in knowing what was required as ICOM don't tell you about it. They spent ages looking for non existent wiring faults and in one case returned the radio for testing. It was returned with a no fault found report and no suggestions. By the time I tripped over the answer he had wasted a day or more removing the panel and rewiring to use the built in I/com. Not happy!