Eeyore wrote in message
...


N_Cook wrote:

In for intermittant loss of one channel but this query is about
overheating.
There are 5/8 inch high feet on the base but unless the owners prop up
on
blocks the whole base gets noticeably hot.

I will be replacing the mains fan as 10 years of much use but any other
observations from anyone familiar with them ?
Dusty inside but not blocking any air throughput and no reported changes
in
fan noise and currently seems the correct sort of air flow for 14W fan.
Design fault concerning airodynamics? There are 2 full width flutes of
the
heatsink that go up to the fan face. I would expect these bits of
aluminium
to be milled out normally in such situations.

Is that the model that has a fan mounted horizontally blowing down onto a
skimpy
heatsink ?

Graham


Blowing up into an adequate , for fan blown, heatsink with a bank of 12
motorola 70483080 TO3 . As far as I can see the 2 uncut-down heatsink vanes
that go across the fan do little functionally for cooling and probably
disrupt the air flow.

The air has to come in horizontally under the base , up the one inch of fan
axis and then have to abruptly divert horizontally again down the 2
(separated by these vanes) relatively small channels in the heatsink. I'll
take a pic perhaps


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
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