Saturday, January 2, 2010

HF Phone Patch

Had some equipment recently donated to our radio club and one of the items included was a Kenwood Phone Patch Controller. I've always been intrigued with the concept of radio phone patches dating way back to when my dad was in Viet Nam and we recieved a couple of calls from him via the MARS system and then again when I was an an airborne communications tech in the Air Force. So I was excited to give this phone patch controller a try. I took a quick look at the intruction sheet and commenced to connect the device to my Kenwood TS-440 and to my analog telephone here in my radio shack. I quickly determined that I had an audio problem. I broke out the multimeter and began to test the pinout on the cables. Bingo, broken wire in the mic plug. The wire was too short and had broken off over time. I soldered in a new wire and was back in business. I also had to modify my phone by soldering in a two wire phone cord to connect to the line terminals on the controller. Would have been easier if I had a two phone jack adapter laying around but I didn't. Besides, I like to solder any chance I can!

So now with everything repaired/modified, and connected up, I was ready to test this thing. I solicited the help of a couple of my buddies to give it a try. I called Dan-KF4MND on the phone and I met Ralph-W4REQ on an available 80 meter frequency. Once I had them ready to go, I threw the "On" switch on the controller. Dan and Ralph were both able to communicate as I provided the keying of the radio when Dan spoke. My first test was a success.

A day later I decided to give it a try again so that I could have a chance to adjust recieve and transmit audio levels and to test the whole thing using VOX instead of having to manual key the radio for the telephone attached party. This time I solicited the help of a couple of other friends. This time I got Will-KJ4PSU on the phone and Kevin-KW4B on the radio. Once I had them both connected I threw the phone patch inline and they were able to speak to each other with me providing the manual keying once again. Once that test was completed, I turn the VOX on the radio to see if that would work. Not quite. When in VOX the radio is staying constantly keyed so I still need to troubleshoot that. No problem. That's half the fun.

Phone patches aren't used very much these days but it sure is nice to have the capability in case it's needed.

No comments: