[Hallicrafters] HT-33A Fan Assembly Needed

[rbethman]

Al,

The folks that made the Amp Supply Amplifiers, used the muffin system 
with up to 3 3-500Zs.  I questioned their setup at first.

They used a plate to hold the tubes above the bottom of the cabinet on 
the right side.  This allowed them to blow the air across the pins and 
the tube bottom, also letting the "majority" of the flow go over the 
envelope and plate cap.

They found a system that worked.  Most of us would NOT go that route.  
We, (Most of us antiques.), would have gone for Eimac sockets and chimneys!

Mine has P.W. Dahl transformer, healthy electrolytics, and toroidal 
tuned inputs.

She'll hold that 300W resting carrier and modulation that comes from a 
DX-60 25W carrier through "old buzzard" turns at the mic!

I can't complain.

Going back to re-organizing house after a carpet cleaning yesterday!

Bob - N0DGN

On 4/16/2010 4:49 PM, Al Parker wrote:
> hi Bob,
>     OK.  I have an HB amp with pr of 4-400's, have a good sized muffin 
> below the chassis to pressurize there & blow air up thru holes around 
> the tubes (no chimneys).  Then a small muffin above them, exhausting 
> air.  Seems to have been OK for yrs, but no long transmissions, no AM, 
> etc.  It lives in the "upstairs shack", the Henry in teh "shop shack".
>     The Henry 3K-A uses a pr of 3-500z's, with chimneys and pretty 
> strong airflow up thru, from husky fan below.  Much better.
> 73,
> Al