[Hallicrafters] HT-33A Fan Assembly Needed

[rbethman]

Al,

Been about 8 years ago since I was looking at the insides of a '33.  SK, 
WC3K was going to let me have it with a spare PL-172, along with an 
SX-88, and an HT-32B.

All had been restored to original.

Can't always remember which big tube needs what!

You "can" get away with the real "froggy" muffins even on 3-1000s and 
4-1000s, although I would rather pressurized the chassis and use a 
blower and chimney.

The 3-500Zs have been real happy with the AC high volume muffin.

(Senior Moment?)

I'll go back to sleep!

Bob - N0DGN

On 4/16/2010 4:05 PM, Al Parker wrote:
> Hi Gary,
> 	Yup, you've got it.  I think some of the guys haven't realized that
> this tube is an external anode, finned, air cooled, tube similar in
> configuration, but bigger, to  a 4CX350 series, etc.  It requires a
> specific air flow to properly cool it, and that necessitates more
> pressure than what's required to cool glass 3-500's, 4-400's, etc.
> 	I had a "modified" HT-33 for several yrs, but sold it last yr due to
> acquiring a Henry 3-KA which replaced it.  You can see at
> <http://www.boatanchors.org/HT-33hb.htm>   I thought there might be a pic
> of the bottom, showing the fan, but guess not.  I do have a complete,
> nearly original, HT-33B that I can drag out&  get pix or info if you
> need.  It's a future project, I do have one good tube for it.  There've
> been threads on the Halli&  BA reflectors every so often abt those
> tubes, and the fact that most glass ones are gassy by now.  It's said
> that keeping filament voltage on them every month or 3 is helpful,it
> might be, but it won't restore a real flat one (experience).
> 73,
> Al, W8UT
> www.boatanchors.org
> www.hammarlund.info