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From: "Stewart Nelson" <sn@scgroup.com>
To: <rsgb_lf_group@blacksheep.org>
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Date: Thu, 8 Jun 2006 10:58:09 +0200
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Subject: Re: LF: BBC 198kHz
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Hi Mike,

I know nothing about the TS-850, but almost all radios have a
trimmer capacitor or other adjustment for the main reference
oscillator.  If you set that properly, the slope of your tuning
error should be nearly zero.  If the (now constant) error is
significant, there might be an adjustment for the 2nd or 3rd
mixer LO, if that is not derived from the main reference.
On some radios, there is a small residual offset (usually caused
by a firmware bug) that can't be corrected.

73,

Stewart KK7KA

----- Original Message ----- 
From: "Mike Dennison" <mike.dennison@ntlworld.com>
To: <rsgb_lf_group@blacksheep.org>
Sent: Thursday, June 08, 2006 10:19 AM
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
> ==========