Sorry, I later realized it is a 6 pin DIN, not 8. Never thought about using
an old mouse cable, great suggestion. But the big question remains: Does
anyone know if the ICOM/Yaesu programming cable is compatible (I suspect it
is). And after looking at the link Ed sent, it appears that pins 1 and 2 are
the pins to use (data and ground). The ICOM/Yaesu cables do have level
converters built into the DB9 head. I'm sure the Kenwood requires the same
sort of interface.

Most of the radios I've looked at use the same electrical-signalling
protocol on their data line - basically, pseudo-TTL or CMOS, just as
if you were coming right out a UART chip. 5 volt, open-collector /
open-drain drivers with a pullup resistor on one side or the other (or
both), with the signalling sense being inverted from that of RS-232.

I've successfully used a Yaesu programming interface intended for the
VX-5 to program an Icom IC-W32A, although I don't remember whether I
needed a custom jumper/adapter to go from the Yaesu's miniplug to the
Icom's minijack.

I believe I've seen _some_ radios which use a three-wire (ground,
send-data, receive-data) serial connection, using TTL/CMOS voltages.
None of the common bidirectional-data-line serial adapters will work
with these, without some extra waving-of-dead-chickens.

My recollection, though, is that the TM-G707A is not one of these. It
uses a single data line, and should be electrically compatible with
the RS-232-to-5-volt-inverted adapters used by Icom and Yaesu HTs.

The most you _may_ need to do, is to pull one extra pin on the
TM-G707A interface to ground or +5 to indicate that you're plugged in
a programming adapter. I know that this sort of trick is needed in
order to invoke the factory-settings/alignment mode, and I have a
vague recollection that it may be needed in order to enable the radio
to distinguish between a memory-programming adapter and an external
TNC... but I could be wrong about that.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

I WAS going to try to diagram my Kenwood PG-4S programming
cable/circuit,,,, but after I opened up the 26pin connector, I gave up.
The tiny PC board inside had more active components on it than I had
realized.... all tiny surface mount. A small 5V regulator IC, possibly
another IC (only had 5 pins instead of 8), and 4 or 5 transistors, a
diode or two, and a few resistors/caps.

Sorry guys, but I don't have the time at present..



Ed