Antonio Vernucci wrote:
Tony....

I think there is something wrong. The manual I downloaded from BAMA says
the oscillator frequency is ABOVE the signal frequency on ALL bands!

73, Roger


Hi Roger,

what you say is interesting.

I have an original SX-101A manual, which I presume should be the same as the BAMA copy. Could you please tell me at which page you read that? In my manual I was unable to find any mention of the oscillator frequency.

I am pretty sure of the oscillator frequencies, as I measured them both with a frequency meter and with an oscilloscope (the oscillator waveform period on 20 meters is somewhat longer than on 40 meters, no question about that). And the strong 9.5 MHz phantoms frequencies are exactly what they should be with an halved oscillator frequency.

On the other hand my receiver was owned by a person who never put his hands in it, but even hypothesizing that someone did something in it, what could he have done to make the oscillator frequency exactly half of what one would expect to be, and on 10, 15 and 20 meters only? Halving the oscillator frequency would cause the dial scale to be no longer correct; matching is instead fairly good (with normal tolerances for a receiver of that kind).

73

Tony I0JX / K0JX


Hi Tony....

It's on page 15 under RF ALIGNMENT. It's the last sentence before the
actual proceedure. I have no idea what could be wrong with your receiver
but to use the second harmonic for mixing is very unusual. The only time
I've seen it used is when a manufacturer was trying to add a "VHF" band
to an early receiver and couldn't get reliable oscillation at the
fundamental frequency.

73, Roger

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