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From: "Alan Melia" <alan.melia@btinternet.com>
To: <rsgb_lf_group@blacksheep.org>
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Date: Thu, 8 Jun 2006 12:00:24 +0100
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Subject: Re: LF: BBC 198kHz
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Hi Mike that does look as though there may be a need for a tweak of the
reference oscillator, but this will need confirming. One problem with some
radios is that they derive all the LOs from the reference except the BFO is
separate, and drifts to its own "script.". This would lead to a constant
offset. Most modern rigs seem to derive all mixing frequencies including the
BFO from the reference which make things easier unless as Stewart says there
are bugs in the firmware or rounding errors. I guess the errors you quote
would not be a problem on the HF bands, many amateurs would not notice them.

Cheers de Alan G3NYK

----- Original Message -----
From: Mike Dennison <mike.dennison@ntlworld.com>
To: <rsgb_lf_group@blacksheep.org>
Sent: 08 June 2006 09:19
Subject: Re: LF: BBC 198kHz


> Thanks to all those who responded to my query about the apparent
> errors seen on frequency standards.
>
> I am now convinced my problem is caused by frequency error in my TS-
> 850. Looking at several standards, the errors are as follows
> (relative to an arbitrary zero):
> 60.0kHz:  -1.0Hz
> 75.0kHz: -0.8Hz
> 77.5kHz: -0.7Hz
> 162kHz: -0.1Hz
> 198kHz: +0.1Hz
> 490kHz (using my LF Tx DDS) +3.0Hz
> Plotting this on a graph shows approximately a straight line. This
> indicates a progressive error as frequency increases.
>
> As a quick fix, I can now use the graph to determine the readings at
> 198 and 60kHz that will give me a zero offset at 136kHz. However, is
> there a more permanent way of overcoming this problem?
>
> Mike, G3XDV
> ==========
>
>
>
> > Nothing unusual seen here - checked against my Rb standard.
> > Walter G3JKV.
>
>
>