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70cm UHF Repeater Build Up, Update 4

Spent a few hours working on the repeater last night. I was attempting to finish up the radio to controller cabling, but it didn't quite go so well.  It turns out to be quite difficult to solder 3 coax audio cables and some control lines to a D-sub-9 connector. Poor eyesight is definitely a factor which I need to remedy! So after all the lines were connected and plugged in to both the repeater and controller I gave it a go. Turn on the repeater and the controller lights up as it should, it indicates that it is sending a PTT, but the repeater does not key up. I check the specs, the TKR-820 needs the PTT line pulled low to activate and the controller sets the PTT line low to send, so that is ok. Tried manually forcing a PTT by back pining the PTT line on the Molex connector and grounding it, no luck there either. I disconnected the cable from the repeater and plugged in a different Molex connector that only has the speaker jumper and the jumper to disable the internal controller. I again back pin the PTT line, and it does key the repeater. So there is one problem. The other problem is some how I slipped and shorted out the +12 coming from the repeater to the controller. The schematics show that there is a 2A fuse on the display unit of the repeater. Hopefully it is not some exotic size fuse and I can replace it easily.
To fix the first problem, I think I am going to have to completely remove the OEM signaling board from the TKR-820. I thought it could live peacefully in the repeater if I ever needed to use it, but it looks like it has to come out, and 3 jumpers installed to route the signals to the rear Molex connector. This should not be hard to do. The second problem is the loss of +12V. The schematic does show a fuse, I just have to find it, replace it, and hope there were no other issues. Maybe I'll get to it tonight or tomorrow.
 
73

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