[Hammarlund] SP600 Perormance - tube shields

[Kenneth G. Gordon]

On 30 May 2013 at 9:57, Wes Bolin wrote:

> Thanks for comments Stanley and Joe.  An alignment will be a near
> future project after I get tired of just playing it.  And, I do see a
> change in performance with the new caps. The signals are
> 'cleaner'--hard to describe or quantify but they just sound better. I
> can easily hear now the distortion of many SW stations for example. I
> have sworn there would be no performance improvement before I made the
> changes, but I was wrong.  And yesterday I decided to tune up to 6
> Meters, and I heard stations via an opening with my 70 foot single
> wire antenna.  Also all of the tube shields were taken off and could
> hear no difference.  Will run like this for a while since its hard to
> find IERC shields. Its still a work in progress, but getting closer to
> the finish line. Wes

Wes:

I proved by experiment some time ago that if you HAVE to use the regular 
solid shiny tube shields, you can reduce the heat of the tubes by 17% by 
painting the INSIDES of those shields with flat black paint.

That way at least some of the heat is not radiated back into the tubes by the 
shiny surface.

Painting the outsides may make even more difference, but I haven't tried that 
yet.

Ken W7EKB