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RCI 6900F w/EPT990013B

Cable Guy

Growth must be chosen again and again.
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Dec 29, 2010
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Hi, I can't find any info on this revision of board, the closest I can find is the 990010X on cbtricks. Does anyone know of any source for schematic?
Thanks
 

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Anyways, this radio has an issue I haven't solved yet. After alignment, which is spot on, AM seems great, but SSB on the LO bands is watery on TX and RX. SSB on the HI bands are clearer, but slightly distorted. I followed the LO/HI switch to the separate xtal oscillators/varactors, and each xtal oscillator has it's own set of 3 inductors, for AM/LSB/USB. I looked at the varactor for the LO osc, its okay. Then I looked at the xtal, it's okay also. Voltages steady. So I though maybe balance modulator, but it does it mostly on LO, with only slight distortion on HI, and I figured it would do it equally on LO and HI if the BalMod was screwy, but I could be wrong.

I'm also thinking FL3, the xtal filter could be at fault, seeing as how it does appear to be a frequency issue as far as I can tell, like I said, slight distortion on the HI bands, and gets worse the lower you go. IDK yet.
 
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