Bob,
I get somewhat different results on my Radio Shack tester. First, my lights
are opposite in color to yours. That's more what I would expect, since RED
usually means a signal is high and GREEN usually means it is low. I would
normally expect the TD and RD lights to be glowing green and some or all of
the other lights to be glowing red. That's because the computer and radio
would normally hold their transmit lines (TD and RD, respectively) low,
except when transmitting. The RS232 handshaking signals (RTS, CTS, DSR, CD
and DTR) would normally be held high (RTS and DTR by the computer, and CTS,
DSR and maybe CD by the radio.) However, it's possible that Radio Shack has
revised the wiring on that tester. Try plugging it in the other way and see
of the color of the lights reverses. I don't think this discrepancy is
important, but other differences between our results *are* important.
First, the RD (Receive Data) light should be glowing a steady color most of
the time, with occasional flickers to the opposite color. I'll discuss some
of the possible causes for this below.
Second, there's a bit of a mystery with the RS232 handshaking signals. I see
that they are all being held high. Normally, I would say that is good
because if any device requires one of the signals to be high, it will be.
But I've determined that the FT1000mp does not raise *any* of the RS232
handshaking signals. You can confirm this by plugging the tester only into
the radio and not the computer (you can see which signals the computer
raises by plugging the tester only into the computer.) The computer would
normally turn on only RTS and DTR. My testing revealed that the 1000mp
actually cross connects DTR to DSR, probably in an effort to satisfy picky
programs that require the DSR signal (that's a little odd, because usually
it's CTS they want to see.) Anyway, you should be seeing only RTS, DSR and
DTR glowing. That's what I see here.
Note that the handshaking lights on the 940 make more sense. RTS and DTR are
on, while DSR and CD are off. That's what I would expect. CTS is on, which
means either the level converter box (IF232C or W1GEE interface) is
asserting that signal, or the cable is wired to cross connect RTS with CTS.
That's a typical technique used to fool the computer into thinking that
signal is being held high by the other device.
This discrepancy leads me to believe that you may be using a funny cable
with the 1000mp -- perhaps one that was wired for the Kenwood or a different
kind of device? Another possibility is that the cable may have some internal
shorts or breaks. If that's the case, you are in luck. If I were you, I
would get a standard prebuilt Radio Shack for connecting the 1000mp to the
computer. It may not fix the problem, but will eliminate one source of
error.
The RD light not glowing is the most serious problem. Several things could
account for this. First, it might actually be glowing, but not brightly
enough for you to see. The RD light on my 1000mp does glow, but very faintly
compared to the TD light being held low by the computer. Second, the cable
connection on pin 3 (RD) might be bad at one end or the other, or pin 3 in
the connector shell at either end might be bad or disconnected from the
cable (here I'm assuming that you plugged the tester into the cable
connected to the 1000mp and not directly into the 1000mp with a 9-25 pin
adapter -- if you did the latter, the cable's not the issue.) The cable and
connectors are easy to check with an ohmmeter. Third, pin 3 inside the
1000mp RS232 connector might be damaged or the internal wire to it might be
broken. If you're not afraid to open the radio, and can get reasonably clear
access to the back of the connector, you can also check that with an
ohmmeter (RIG UNPLUGGED!) I haven't popped the cover on my 1000mp to see if
that's reasonable to attempt. It's possible they used an edge connector
soldered directly to the PC board. If so, it could be a bad solder joint to
pin 3 or flexing at the connector may have damaged the joint or the PCB
trace leading to it. All that can be determined through visual inspection or
use of an ohmmeter (RIG UNPLUGGED!)
If the cable and connectors are good, and the RS232 connector inside is OK,
then it could be a bad RS232 level converter chip, a bad TTL driver chip, or
bad wiring between them. A long shot is that it's a bad pin on the CPU or
one of the chips between it and the level converter (or a bad wire in one of
the harnesses.) I'd probably scope those things out myself with a DVM and
ohmmeter, but many ops would be more comfortable returning the rig to the
factory for service, especially if it's still under warranty.
For those that are interested, I did determine that, as the connector
diagram in the manual implies, the FT1000mp does not require any of the
RS232 handshaking signals (RTS, CTS, DSR, CD, DTR.) CT 9.37 on my particular
computer (a Dell) did not require any of the signals either. I was able to
get perfect communications in both directions with just TD, RD and GND
connected. That may not always be the case with all computers and logging
programs.
In addition to the Radio Shack tester, I did my experiments here with a
1000mp, CT 9.37, COM1 and a fancy RS232 breakout box (the $250+ variety that
I picked up at the Rochester hamfest for $25 -- best bargain ever!) This box
lets me selectively interrupt and patch signals, and slows the signal pulses
down enough so they can be clearly seen.
Hope this helps. If you have any questions, just ask.
73, Dick WC1M
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