[time-nuts] 5070B once more.... (actually 5370A fans)

[Hal Murray]

> This is incorrect.  ECL components require a minimum airflow velocity
> that is rather high.  The purpose of the large fan is to maintain this
> velocity.  If a smaller fan is used, the ECL components will get
> hotter, even though the air flowing past them is not much hotter.
> When you say the fan didn't make any real difference in cooling inside
> the unit, did you measure the temperature of the ECL DIP's?

How much ECL is used in a 5070?  How tightly are they packed?  How much of 
the heat goes directly from the chip to the air rather than from chip to 
board to air?

How much room is there above the chips?  Many years ago I saw some neat 
add-on heat sinks.  They were heavy copper foil with double sided sticky 
tape.  They had a couple of fins sticking up into the air flow.  They weren't 
serious heat sinks, but good enough to help if all you needed was a little.



-- 
These are my opinions, not necessarily my employer's.  I hate spam.