Load resistors are usually Carborundum (trade name) or similar and come in a
wide range of values and wattages.
They are pricey new but do show up on Ebay and flea markets once in awhile.
Bring an Ohmeter or get a guarantee from a mail order seller as the value
can change considerably over time. I have a few that were still sealed when
purchased 100W ones that measured 68-70 Ohms. A little bit of file work and
sealant returned them to 50 Ohms; they have remained at 50 Ohms for over 10
years.
One way to possibly cheat the price if the load is strictly for HF is to
find a 200 Ohm or higher version and use a powdered iron unun. Ive used a
reverse connected 12:1 balun to test old style push pull balanced output
transmitters and amps as well as feed coax lines as Im doing with PP 211's.
Carl
KM1H
Carl
KM1H
----- Original Message -----
From: "Keith Schreiber" <schreiber@alltel.net>
To: <amps@contesting.com>
Sent: Sunday, November 11, 2007 6:28 AM
Subject: [Amps] Bird 1KW+ Load Resistor
> I'm looking for info and leads on purchasing a replacement resistor, for a
> Bird oil-filled load. Bird tells me they no longer have parts for, nor
> support "this obsolete load" which I believe is from the 1960s. The model
> number on mine is 888 and is similar to models 6835, 8813, 8832. The
> sticker on the front says 1200W continuous - 1500W for 1/2 hour.
>
> A possible resistor part number is 3510-026-2 (this info from another
> ham.) The resistor is exactly 12 inches long X 7/8ths OD. It is
> hollow. The ID is 5/8ths inch, making the walls 1/8th inch thick. It has
> a 5/8th inch copper band at each end for connection. It's white ceramic,
> with a black film element. (If you think you have one for sale, I can
> e-mail you a picture of what's left of mine.)
>
> Do you have one of these lying in a drawer somewhere, or know where I
> might find one? Or perhaps a resistor from some other vendor that might
> work? One more question: Does anybody know what that incredibly
> foul-smelling, dark colored coolant in these loads is? Strange
> properties - thin like water but freezes above 32 F ????
>
> Thanks for any leads or info & 73
> Keith W8KTH
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>
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