My primary radio, a Yaesu FT-857, half-died during Field Day, so I sidelined it for debug later and continued with my other HF rig.

Last night, I tore apart the radio and the Signalink attached to it, and dragged my oscilloscope out of storage, in order to probe into why the audio wasn’t modulating any output during Field Day. The Signalink was definitely generating audio, and I followed it from the internal DIP jumper block to the RJ45 connector to the DIN end of the cable. Tried to probe the radio board, but the DIN jack pads are under the board and would take desoldering and unmounting some power transistors from the chassis to reach the underside.

So I connected a dummy load, powered up the radio, changed the internal and external meters to show power and deviation, and sure enough once I set the power over 5W, it was modulating and pushing power out to the load. I think this is just another case where the DIN plug and jack are having connection issues; this has cropped up before.

I guess I’ll either have to replace the DIN jack, or just keep jiggling the cable.

The second issue was more worrisome, because when it happened, it looked like I fried the CAT cable and caused the driver to fritz. Windows alerted that a driver was crashed or incorrect. I can’t remember the exact notification because I had so much going on at that moment. But the PC and the radio were unable to communicate shortly after that. I removed the CAT interface from Device Manager and rediscovered it. Got a different COM port number. Still couldn’t reach the radio.

Then I noticed something in the manual; the CAT port also changes function if you connect it to a linear amp or an antenna tuner, and you have to select which of the three functions that port serves in the menu options. I know I had it set to CAT operation, but I checked again.

I don’t know which dumbass set it to TUN for tuner, but once I changed it back to CAT, the PC was able to talk with the radio. God, what a stupid ass; someone should punch that guy.

In short, the rig works, has always worked, and would continue to work if the operator knew WTF he was doing.

Published by Shawn

He's just this guy, you know?