March 10, 2024
After two sessions trying to get the NXP LDMOS pallet to play nice, I replaced it with a W6PQL pallet. It took some fiddling to re-jigger the 12 vdc bias circuit, re-do the 50 vdc VDD lines, and solder the RF input and output coax in place. Slipping two layers of index card stock between the circuit board and the heat-spreader works really well - otherwise the copper heat-spreader draws the heat off too fast to get a good, clean solder joint. I could even solder the conformable coax in place with a 45 watts HAKKO soldering station cranked all the way up.
Today was the smoke test. 3 watts of drive = 400 watts. That's 21 db gain which is very nice! I have some level setting to do with the transverter's 144 MHz drive level, even at 0% power indicated, my IC-9700 hits the transverter a bit too hard. A 3db 10W attenuator is on the way.
I've also discovered my usual operating spot in the barn just south of town is not a good location for 902 EME reception. There are just too many 902 - 905 devices chirping away across the band. For the next test I'll retreat to the mountain cabin just north of Yellowstone Park as soon as snow comes off the access road.
In the meantime I've been streamlining the station's cables and generally getting things ship-shape for some summer travels with 902 and 1296 gear.
Onward!
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| Finished soldering the .250" conformable output coax in place. Note the card stock to be removed. |