[Premium-Rx] WJ-8711A encoder noise elimination

[Bob Betts]

Hi Steve and Group:
First, I want to thank you for all you've done for us. Much of the manual material has been very helpful to me.
 
I did a similar mod to an 8711 a few years ago. I no idea of the problem until I read Dallas' article back then. This turned out to be kind of fortunate since a few of the guys have complained about the encoder's feel anyhow. So some added hardware that would change the tuning feel could also be used to affect the fix. 
 
I didn't do any extensive testing, as you did, other than watching the noise floor on a scope and using a sniffer coil to survey the radio all around  to see what's being radiated and where. Bottom line; the fix is effective and really works.
 
So, again, I want to thank you for sharing and for the recent noise abatement info that I absolutely concur with.
 
Good signals,
 
Bob, N1KPR


http://www.bobsamerica.com/swl.html
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--- On Sat, 7/21/12, Steve Pappin <pappy92651 at yahoo.com> wrote:



Re: WJ-8711A encoder noise elimination and initial findings

The work that I am doing is based on initial findings from Dallas Lankford. 
Digital noise from the 8711A tuning encoder shaft actually extends well 
below 15 MHz and raises the overall noise floor. This has the effect of 
making the 8711A less sensitive. Depending on any number of variables this 
might become more or less of an issue. Systems using remote high gain 
directional antennas might not be affected. Systems with local antennas, 
short feed lines, or active antennas will definitely be affected.

edited