[CQ-Contest] Save 1 serial port

bogus at does.not.exist.com bogus at does.not.exist.com
Wed Sep 24 11:49:48 EDT 1997

Hello All,

This shall be well known by most of the users but I think some may not.

I've wired a cable to control the FT-1000MP with computer a few months
ago and it has been working fine ever since. Yesterday I decided to take
a look on it and found out that the DTR pin was not being used by the
radio, so, why not use the same serial port to send CW from either CT
and the logging software?

I went to PY2BW's home and discussed with him this possibility. Then he
re-wired the cable using the DTR pin (pin 4 on DB-9, pin 20 on DB-25),
soldering a 1K resisor and a 2N4401 (or equivalent) transistor. The
resistor was connected to the DTR line and the NPN transistor base. The
emitter of the transmitter and the common ground line (pin 5 on DB-9,
pin 7 on DB-25) were connected to the ground lead of the keying cable.
(please refer to CT or loggin software manual).

This parts were arranged inside the DB-9 with the transistor collector
connected to the hot lead of the keying cable which one is plugged into
the radio key input jack. The manual keying was plugged in the front
panel key jack.

Now I can switch the CW sending by pressing the Keyer button located in
the radio front panel. Better yet, no extra cable, no extra interface
and one serial port saved.

73 DX de PY2YP - Cesar
(ZZ2Z in the contests)
Mailto:py2yp at pobox.com

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