I have a Hallicrafters HT-33A amp sitting on my project shelf. The orginal
swamping resistor network consisted of 3 200 ohm 20 watt globar resistors.
One is missing and the others have changed in value.
I might add that I chased down the original manufacturer of the Glowbar
carbon resistors. That particular size would be a special order and was
going to cost about $50 each with a $250 setup charge. I suppose the cost
would go down with a larger ordrer.
Would a network of the MOF resistors described below work, assuming that
the use of a 100 watt exciter work as a suitable replacement for the
origninal Glowbars? I was thinking of using a seriers parallel network of 6
100 ohm resistors. Where do you order the Matsushita 3w-rated 100 ohm MOF
resistors described below?
It would be really nice to get the SX-101, HT-32 and HT33A going for the
cold nights a head
TNX ES 73
Jim Zellmer, KA0VSL
-----Original Message-----
From: Rich Measures <measures@vc.net>
To: Robert Wood <w5robert>; amps <amps>
To: <amps@contesting.com>
Date: Saturday, August 08, 1998 1:35 PM
Subject: Re: [AMPS] Carbon Composition Resistors
>
>>
>>Searching out a supply for Carbon Composition Resistors.
>>These are used in the input circuit of my AMP.
>>I see them in the MOUSER catalog but only up to 1/2 watt??
>>The local parts house had very few almost all now metal film.
>>--
>Provided one selects MOF resistors with low-inductance, MOF resistors
>are superior to carbon-comp resistors in RF service. For instance, the
>Matsushita 3w-rated 100 ohm MOF resistors we use in our suppressor
>retrofit kits have c. 11nH of intrinsic L, and will safely dissipate 12w
>for one-hour @75 deg. F ambient. The trade-off is that such a resistor
>can Not be used as a coil-form for a suppressor-L. .
>- later, Robert.
>
>
>Rich...
>
>R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
>
>
>--
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