[Elecraft] XV50 Cooling

[n0jrn]

Thanks Don:

I bought this unit unbuilt from another list member and it is a very early 
model.   It has no vent holes at all !

I am driving with low power and therefore have the attenuator resistors 
bypassed.  So not worried about heat from that area.

I do have the feet on the transverter so air flow under it is good.

My concern stems from a reduction of output power after using the unit non 
stop for a period of time.  My fear is the power module is getting hot and 
falling off some.

Module was installed using the heat transfer pads correctly located.    I 
did not use heat sink compound.

This unit has the old style power module in it  ( M57735 )
This predates requirement of setting the PA bias in the XV50.

Just thought I would give it a little more air to help my PA live a little 
longer.     :-)

Guess I'll drop Gary a note and see if he has a spare set of panels.

Thanks again Don and have a great day.

73          Jerry              N0JRN

On 6/2/2010 10:36:44 AM, Don Wilhelm (w3fpr at embarqmail.com) wrote:
> Jerry,
>
> There are holes in the top cover that are "supposed" to be positioned
> above the attenuator resistors, and the new transverters have holes on
> the bottom on either side of the power module.  I am looking at a rather
> new XV50 right now that has come in to me for repair.  The builder did
> not position the top cover holes over the attenuator resistors, but the
> holes are in the cover.
> If you are driving the transverter from the low power outputs, the
> attenuator resistors are not used, so that source of heat is a no-op,
> but the resistors will heat up if higher power is used to drive the
> transverter.
>
> I do not believe additional ventilation holes are needed in most cases.
> If air flow below the transverter is available (do not operate it
> without the feet), the cooling is adequate.  It seems to me that some
> operators get concerned with any heat generation, but in reality, if it
> is cool enough you can place your hand on it for more than 30 seconds,
> it is not hot enough for concern.
>
> Earlier transverters did not have the holes in the bottom panel, and
> some very early ones did not have the vent holes in the top cover.  Yes,
> these may need additional vent holes, especially over the