Sunday, September 10, 2023

Another repeater rebuild

Since 2003, I have been the hope to the former Ashwabenon High School Tech Club's VHF repeater. It started with a Micor at the high school and about 2004 is when we rebuilt it using a Kenwood TKR-750.

I live on a bit of a high spot, though most the area is pretty flat with the exception of Scray's hill where the TV transmiters are.

Over the past 20 years I have basically come the conclusion a 50 ft VHF repeater serves little purpose. I've watched the noise floor grow considerably.

The concept this lower profile repeater was started by a friend that will retire in less than 5 years and I promised him long ago I would continue being its home till then. The concept started in the 90's when all the repeaters were very active and it served as a place for a younger generation to hang out and "shoot the shit."

While I wasn't really interested in another rebuild, I welcomed the Kenwood TKR replacement. The TKR-750 and its poor internal isolation between the transmitter and receiver at 600 KHz splits. (The only solution to that noticeable desense and annoying mixing is to run the thing less than 15 watts, use a larger split or, get a new repeater.) The guy who started the club donated a Motorola Quantar which is capable of mixed mode; analog and P25. I am not sold on any specific digital mode I do see P25 as somewhat logical. Its been around since the early 90's so there are options on the used market for radios from several manufacturers. The vocoder is also out of patent and there is a good sounding open source implementation.

It will mostly be used in analog mode, but this does permit others play with another mode.

So I am still doing things in ham radio for anyone wondering.