Re: {Collins} S line zero-beat issue in Transceive Mode?

[Mike Waters <mikewate@xxxxxxxxx>]

Correction. I just looked at my 75S-3 notes.
I added an 8-50 pf ceramic trimmer (probably NPO) in series with Y16, the
USB BFO xtal.
This is only on one sideband, correct?
My gut feeling is that if the frequency is truly off by 500 Hz as stated,
this may not help solve the problem. You may have other issues in that
circuit, or the voltage feeding it.

73, Mike
www.w0btu.com

On Sun, Nov 23, 2014 at 2:40 AM, Mike Waters <mikewate@xxxxxxxxx> wrote:

> I solved this very issue by padding the BFO crystal(s?) in my 75S-3 with
> some small NPO silver mica capacitors, IIRC. I forget whether they were in
> parallel or in series with the crystal, or what the values (determined by
> trial-and-error) were. But it has remained stable for the past 35 years.
>
> 73, Mike
> www.w0btu.com
>
> On Sun, Nov 23, 2014 at 2:13 AM, David Harmon <k6xyz@xxxxxxxxxxxxx> wrote:
>
>> There is no alignment procedure to make the S-Line transceive on the same
>> frequency.
>>
>> On frequency transceive operation is determined by the BFO xtals in each
>> unit.
>>
>
>