Hi Greg - Points well taken.
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My PCM1804 chips came in a day early so I decided to take a crack it this evening. Success, it worked!
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I got low temp solder paste and some paste flux which helped tremendously. I did use an iron and wick with solder flux paste for IC removal but used the low temp solder paste and hot air to reflow it into place. Textbook reflow! I used the medium diameter nozzle and about 700F air temp and didn't hold it there long and it 'took' right away. Probably could have used 600F for reflow.
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Bottom Line: The PCM1804 was bad even though there was no shorted Vcc or Vdd lines and normal current draw/heat dissipation. I ordered 3 total so have 2 spares. Once I got the flux cleaned off with some IPA, the unit fired right up and sounded great.
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The issue with the transmitter only able to function when the sidetone abs/rel was toggled is gone, so it was an issue tied to the defective 1804. All issues are now resolved and now am looking at some filter sweeps. Images down at least 33 to 47dB. The RF Filter Sweep shows a couple of filters not 'centered'. The 60 and 17m filters are not centered. The 60m filter response is a little high and the 17m response is a little low causing each passband to be located on the skirts. I wonder if this is something that can be corrected or if it is a trade given the limited number of filters to work across the mid-bands.
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My QMX kit took about 8 hours to build and about a week to troubleshoot and fix. But thanks to this group, I wasn't left out in the cold trying to figure this out on my own. Thanks everyone.
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So, there you go, all fixed now and should be able to enjoy an operational QMX now.
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73
WV0H Myron
WV0H