[Yaesu] Crossband repeating with Yaesu radios

[John Geiger]

Kenwood has a few rigs that can be interfaced to one of their FM rigs
through the 6 pin mini-DIN jacks on each radio to let them run in crossband
repeat.  These rigs include the TS480, TS590, and I think the TS570.  The
TS2000 can even do crossband repeat using both of its receivers, so an
extra radio isn't even needed.

Has anyone tried doing this with other brands of radios.  For example, take
a Yaesu FT2000, turn up the squelch, and run a cord from the external
speaker jack to the mic jack on a Yaesu FT857D, which has VOX turned on.
When the squelch opens on the FT2000, it should key the 857 and transmit
the audio from the FT2000.  Then do the opposite for the audio going the
other direction-run a cord from the speaker jack on the FT857, with the
squelch turned up, and tuned to 444.000, running to the mic jack on the
FT2000, which has VOX turned on.  When you transmit on 444.000 with an HT,
the 857 would pick it up, open the squelch, and send the audio to the
FT2000 to be transmitted on 50.125, or whatever frequency you like.

Has someone successfully done something like this?  Are there reasons why
this wouldn't work as planned?  It looks good on paper, at least.

73 John AF5CC