Thursday, I took the Heathkit keyer apart, spread out the schematic and began poking around. It looked to me like everything was working the way it should, so I buttoned it all back up, built a cable to connect it to my IC-735, and voila it keyed the rig perfectly.
My only guess as to why it didn’t work right before is that I had the positive and negative contacts swapped. If you’re keying the transmitter with a straight key, swapping them doesn’t matter–the key is only a mechanical switch after all, and the current doesn’t care which way it flows through a switch. But the output of the keyer is a transistor, and current flows only one way through a transistor, so you have to connect it properly.
Instead of using the capacitive paddles built into the keyer, I’ve opted to use the Bencher paddle. I played around with the sensitivity adjustment for the capacitive paddles, but I just couldn’t find a setting that wasn’t too sensitive. As a result, I was getting a lot of phantom dits.
The problem with using the mechanical paddles is that instead of using a stereo phone plug, Heathkit decided to use a small header. This is, of course, a lot less standard than a phone plug, and the local Radio Shack did not have the proper connector. To use the keyer today, I had to use some clip leads and Mickey Mouse it. I hope that Purchase Radio will have what I need, but if not I may have to modify the keyer to accept a phone plug.
The good news is that I made eight contacts today using the paddle/keyer combo. I asked the operators on the other end to be a little patient, and fortunately for me, they were, for the most part. I think I got better along the way, although during the last contact, I got tired and began to lose concentration and started making a lot of mistakes. All in all, though, I think I’ll like using the keyer once I get proficient with it.