[R-390] Scale varies band to Band

[Bob Camp]

Hi

A *long* time ago I ran into the guy who designed the oscillator deck in the R-390A. When asked "why no trimmers?" the answer was - It wasn't in the spec. Put another way, they could do everything they needed to do without them, and they cost money ….

If you can come up with a big enough pile of crystals, you can sort them into groups that match fairly well. It's a time consuming process and should be done tin the radio you will be using them in. 

Bob

On May 13, 2013, at 4:42 PM, Gordon <gordon at n6wk.com> wrote:

> Is it normal for the scale to vary a couple Kc's band to band?
> For example, If the Calibrator is dead on 7.500 on the 7 Mcs band, is it normal for it to be maybe on 8.502 on the 8 Mhz band and maybe 9.497 on the 9 Mhz Band?
> I do not see any trimmers to bring each crystal dead on. Am I missing something?
> 
> 
> Thanks,
> Gordon
> N6WK
> 
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