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" <[email protected]>
To: <[email protected]>
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
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