[TenTec] Ten-Tec 811A or 572B amplifiers?

[Kc9cdt@aol.com]

The advantage is the 572-B is more rugged, the Centaur and Collins 30L-1 are 
running those 811A's pretty hard,  they get pretty hot.

Many have replaced the 811A's with 572B's and been happy about the change...

Also, be careful with the 811A's in amps where they lay horizontal. ONLY some 
811A's are designed to be mounted horizontal. The others will short out as 
the components sag and touch when very hot.

I use the 572B's in the 30L-1. Works great for a long time.

Of course if you are ery conservative in operation the 811A's work well too, 
just watch that grid current!

FWIW.

73,
Lee, KC9CDT