[Johnson] Ranger VFO chirp on 40 Meters

[Eddy Swynar]

On 2014-03-07, at 9:52 AM, WQ9E at btsnetworks.net wrote:

> Jim,
> 
> Eddy correctly identified the problem.  It is from RF entering the VFO on 40M where it is operating on the same frequency as the final.  This problem is even more common with the higher power Valiant although my even higher power Viking 500 shows no sign of this problem and I have never heard of anyone having it with the 500.  In really severe cases it will also cause some FM when operating AM.
> 
> The only instance where I had to go beyond tightening all of the VFO mounting screws properly (surface oxidation causes poor contact with age) was in an early Valiant which had a long factory slot cut into the case where the VFO shaft enters.  I had to add some metallic shielding tape to this one and it cured the problem.
> 
> I expect the problem doesn't show up on 160 since it takes a bigger "leak" in the shielding to let this lower frequency radiation into the VFO.
> 
> It can be successfully cured, I have a Ranger 1, Ranger 2, Valiant 1, Valiant 2, Viking 500, Navigator, and Pacemaker and none chirp on 40 CW.
> 
> Rodger WQ9E




Hi Jim & Roger,

In my case all it took to fix the problem was a re-tightening of all of the VFO enclosure screws---yes, the solution to such a vexing issue really & truly was just that simple!

~73~ de Eddy VE3CUI -VE3XZ