[amsat-bb] Recording TX & RX from one or two radios?

[Ken M]

Hello AMSATers,

I'm looking to record both TX and RX audio to a digital recorder, either 
at the QTH or in the field (but mainly in the field), in either of two 
common scenarios:

1. TX from one radio, and RX from a different radio (as in satellite use 
with one radio for uplink and one for downlink).

2. TX/RX from the same radio (as in a full-duplex radio for FM 
satellites, or for non-satellite use).

I'm wondering if you know of a device (or a published circuit design) 
that will allow TX/RX recording while isolating the radios from each 
other and/or a radio's TX from it's RX, while linked to the same 
recorder? I have to believe this is a well-solved problem within the 
satellite radio community but I haven't found too many ideas for field 
use. This is seems to be an easier problem to solve at the QTH if 
recording to computer, with various sound interfaces (Signalink, etc.) 
so my main interest is in field use with a digital recorder so I can 
record my QSO's while juggling two radios plus antenna, etc. The easy 
alternative is just to record the RX side, which is easy, and works for 
logging but doesn't give you the full exchange.

Thanks & 73!
Ken VA7KBM