Lee I'm a amplifier snob...I really like (most) Alpha amplifiers. Alot of
articles have been written to salvage MLA2500's and I bet they all work ok.
If the filament voltage is correct and the air flow is sufficient, most any
triode you can cram into the cabinet will probably make power.
The 3CX800 requires very little drive and it would be real easy to hurt it
with a 100 watt exciter. I suppose if you swamp the input real heavy
everything would turn out ok. Also a muffin fan just won't blow air through
those radiators...you'd have to make some arrangement about that. Plate
dissipation is only good if you remove the heat. If memory serves me
correctly, the heat from the tubes in that amplifier goes directly into the
amplifier which is a really funny place to put it!
One good thing about that amplifier is the very sturdy steel box it's in.
Best of luck and keep building!
At 11:46 AM 3/11/97 -0600, you wrote:
>I've read your post with great interest. My friend has an MLA2500 that is
>still in good shape, but he is worried about find rub replacements for the
>8875s. I was wondering if you ever converted this amp with a 3CX800 (single
>tube)?
>
>The reason why I am asking...I met a guy at Dayton who claimed it was a
>simple task to do...basically mounting the tube and hooking it up. This is
>different than the Svetlana tube coversion which was published in QST
>several years ago. That used tetrode and a screed supply. But the guy at
>Dayton (and I lost his card in the shuffle) stated that it can be done quite
>easily with a 3CX800 and have more plate dissapation that with two 8875s.
>
>Comments?
>
>Lee
>k0wa@southwind.net
>
>
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