To recap the problem:
I was using the opto-isolator circuit shown on page 55 of the Writelog manual
to key the rig. The rig would go into transmit and not send dit and dahs and
stay in transmit until I unplugged the key or sent something with the paddles.
Now, I have no idea but for some reason the opto-isolator circuit just would
not work. It seemed as if the opto was holding the key down. The voltage to
the DTR line would fluctuate with the keying and go back up to minus 9 when it
was finished. The resistance across the key side would stay low so the key
stayed keyed until I removed the jack or keyed the rig with the paddles. I
tried two different optos so I don't think it was defective. I also tried a
couple of different resistors instead of the 560 shown in the book. Nothing
I switched over to the other circuit shown for the LPT port. The one using
the NPN transistor but I hooked it onto the DTR line of the serial port. It
works like a champ.
So problem solved and I don't know why. Just put this in your book of tricks
in case someone else comes up with a similar issue. I don't know enough to
tell if this was my computer or the Orion. However, the Orion does show 4 volts
across the key line. Is it possible this was working against the opto?
Fredericksburg, Virginia USA
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