I mentioned in a previous post that one of the “hidden features” of the PL-990 series is the ability to calibrate the radio so that the frequency display is correct when say, you zero-beat an AM broadcaster/carrier in SSB mode.
For normal AM broadcast listening, you’d never notice the frequency discrepancy on the display. When I used the PL-990 in ECSS mode, though, my frequency display is a few Hertz off pretty consistently across the spectrum.
Our friend Gilles Letourneau (at the Official SWL Channel) recently told me that after a couple hours of tinkering with his PL-990 last weekend, he was able to calibrate it but was so deep into the process, he wasn’t able to document exactly how he achieved it. Of course, now that it’s accurate, he doesn’t want to inadvertently harm the calibration. I don’t blame him.
Big news is he’s confirmed that it’s possible.
I’m curious if any PL-990 or PL-990x owners have successfully calibrated their receiver. If so, please consider sharing your procedure with us!
“Tune a strong signal in AM .. like WWV then use LSB USB modes to fine tune the receiver as close to zero beat as possible. Then simply press and hold the USB key until display light flashes two times … you will be all set and calibration will work !”