>After nearly 25 years of service, my trusty MLA-2500 popped a hi voltage cap.
>
>The cap was shorted and one with similar value (but much smaller
>physically) was dropped in. The amp apparently works fine. It made proper
>voltage and put out the correct amount of power on the low voltage setting.
> I didn't try in on high power - didn't want to push my luck.
>
>The capacitor bank should be replaced. They are all old enough and have
>lots of miles on them. Does anyone know of anyone who makes a drop-in board
>of caps like Harbach does for the Heath amps?
>
No, Mitch, however a solution is to buy new caps and fasten them to the
board with silicone-rubber/RTV. Digi-key carries 500v Panasonic
[Matsushita] electrolytics. A bit more C than 100uF each would be mo'
betta. Panasonic 100k-ohm, 3w equalizers would also be an improvement.
>I've seen some modifications where other sized caps were used. I'd rather
>not mess around with with new physical construction, if I can help it.
>
>If a drop in cap assembly is not available, are there any recommendations
>on caps to use which would equal or improve performance. The caps are 100
>uF, 500 volts, wired 3 in series (total 6) for a voltage doubler circuit.
>
100uF divided by 6 [c. 17uF] seems a bit light for FWD service.
>Thanks for any help you can provide.
>
>73, Mitch W1SJ
>
>Mitch Stern
>w1sj@arrl.net
>
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>
- R. L. Measures, a.k.a. Rich..., 805.386.3734, AG6K,
www.vcnet.com/measures.
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