[Amps] Parasitics & Filament Sag

[John Vickers]

----- Original Message ----- 
From: "Mike Sawyer" <w3slk at uplink.net>

>    I used nichrome and they worked. It was the only substitution made. The
> original suppressors were only in the amp for a short time (two weeks in
> intermittant operation). So it sounds to me that there is some merit to 
> what
> Rich is saying.

I believe you said this was a pair of 813's. I still have one I built in 
1965 running 3 813's and its never had an anode suppressor in it. Just a 
wide copper strap from the plate choke (homebrew) to the tubes. Never had a 
problem with parasitics. Used on 80, 40, and 20 m. Would run it with 1, 2, 
or 3 tubes by just unplugging them and left the strap hanging. They were all 
mounted in a straight line so plate lead was excessively long.Certainly 
wasn't due to my engineering prowess--- was only 15 yrs old at the time. In 
my case--- I didn't need *any* suppressor. In your case you did. It would be 
beneficial if you had figured out WHY.
73, John WA4TT