LF: 500 kHz

To:	LF Group <[email protected]>
Subject:	LF: 500 kHz - Fans
From:	Chris Osborn <[email protected]>
Date:	Sat, 20 Jun 2009 06:34:25 +0000 (GMT)
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LF,

I've nearly completed my new PA for 500 kHz and have now managed to

stop destroying FET's.

Unfortunately I have an unusual problem in that the heatsink cooling fans

are going U/S.

I have used 24 volts brushless PC-type fans and after a while they

either die completely or start to go backwards slowly. . .

The fans may be slightly over-run but only by a volt or so and on key-up

(unregulated supply) and are situated about 50 mm (2 inches) from the heatsink.

I have rf decoupled them from the supply but maybe not well enough !

Any suggestions in curing this problem would be most welcome.

73 Chris G3XIZ

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LF: 500 kHz - Fans