Well, that
was fun. I found 2 flaky sma cables, one
bad power pin for the relay 3 board, and a loose power pin on another board.
The shack
and the rig is a big mess. Wires, test gear, parts all over the bench. In fact
I spread out over 3 benches.
The good
news is I think I’ve licked the noisy signal issue. Got rid of all the 12v return lines and the
ground loops and go figure… no noise.
The carrier adjustment is better as well. Not quite so sharp. I don’t like the fact that the shield is no
carrying the 12v returns to ground, but I didn’t have much choice.
The design
of this rig was chosen so I could easily replace individual circuits/modules as
I learned about them and may have made some improvements in the design. I didn’t realize at the time that the design
would create problems. Ie the ground loops.
Another problem I found was my choice of rf cables. I went with pre-made sma cables and that was
not a good idea. They are not the best
when used in tight spaces. Sharp bends
and loops are needed and this has put pressure on the connectors and this has
made for intermittent connectivity. Next
time I’ll make my own cables and use RG174.
So tomorrow
I’ll set up my KX3 again in the backyard and record the transmissions from the
LBS rig. Last time lots of evidence of
ground loop noise and this time, let’s hope no noise. Preliminary testing suggests no noise.
Here's a picture of the LBS rig in its present state. If it proves to be quiet, then I'll clean up the cabling.
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