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AMT-5000 problems peaking RF output

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I am now even more frustrated than I can possibly describe in a polite manner. I've tried everything I can think of plus what has been suggested. No matter what I do I get 0.144v when measuring RF input current, and 2.688v when measuring RF input voltage. This is across the entire range of  Based on the formula this means the transmitter is putting out less than 4 mw (0.0387072). I get this value across the entire range of tuning C1.  As Carl suggested I confirmed that S1 was not connected (it never was). I powered off the xmtr during every change just to be safe to the transmitter.  I tried the RF peaking procedure using  each of the three jumper positions suggested by the manual (S8,S9,S10). Same results.  I also replaced this jumper with a brand new one in case the first one was bad and again went through the peaking procedure using all three jumper positions again. Same results. I inserted a capacitor in the antenna line. I went from feeding the coax to just a long wire again. I changed from using my cheapo Extech VOM to my Fluke 110 DMM. I also tried adjusting c25 to see if the readings changed. They did not. BTW I still don't get why the manual says to keep the slot of C25 lined up front to back but since you can rotate this cap several times the manual doesn't mention how many turns up or down this cap should be rotated when the slot is lined up front to back.  Two days ago I was getting the best range ever even getting over the mountain  behind my house.  Now I don't even get down to the end of my driveway (800ft).. If you can see it on the attachment, that longes red line was over 9000 feet. How it got over the mountain and I could hear it baffles me, but anyway that was 2 days ago, not now.  Any ideas?

carl AvatarApr 18, 2017 16:14:26 GMT -4 carl said:Oh, That's Right, the CoaxOver the course of the back and forths I lost sight of the coax and wasn't sure it was still in place or not. Now that we know, I'm guessing that all that coax is swamping the signal with capacitance that is throwing it out of the designed range. By adding a 20 pF or other small value of capacitor in line with the antenna you might be able to get the tuning back into range.

 

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