(Reminded by the "Restringing the Model 200 VFO" thread)
Looking for the "department of antiquities" here: my 505's dial calibration is
off, all bands. According to the manual everything derives/multiplies from
the PTO. While the amount varies by band, when the PTO fundamental frequency
is taken into consideration, it's surprisingly consistent. Here are some
approximate numbers for the "0" and "500" dial marks I came up with
by "sniffing" the PTO fundamental with a small digital SW portable:
Band VFO low VFO high Meas low Meas high Diff L KHz
Diff H KHz
80 6.250 6.500 6.234 6.484 -16 -16
40 5.333 5.500 5.318 5.485 -15 -15
20 5.000 5.500 4.987 5.480 -13 -20
15 6.000 6.250 5.980 6.234 -20 -16
10 6.333 7.000 6.314 6.988 -19 -12
I'm guessing that a cap or something in the PTO circuit may have changed
value. From the manual, it appears that an across the board oscillator
realignment is probably needed - no quicker way? I hadn't tried to do
anything with it to this point as the 505 mostly just functions as a RX for
casual listening on the bands, and I've somewhat learned to interpolate to
find where I want to be.
Otherwise, if someone out there is nostalgic for a 505, I'd be willing to
consider letting it find a new home as I probably won't get around to doing
anything with it in the forseeable future. Like many other Americans, I
probably have way too many projects and too much "stuff" (but I digress....)
TNX/73, Al
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