[Milsurplus] field phones

[Robert Newberry]

Anyone have a website, or information on a "how it works" on field phones?
I want to learn more about them.

I was looking at the GRA-39's and wondering how easy would be to build
something similar to that, just to be able to remote control a FT-897D with
two wire field phones.

The Clansman PRC-351 has the two wire post on the radio for field phone
control, and you can even back to back two sets for auto re-broadcast. I
got to thinking I wonder if I could build something simple just to connect
to an 897D.

I'm aware I could purchase a GRA-39, but I thought I would see if something
simple could be made up to accomplish the same thing without all of the
bells and whistles.