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XV50 Cooling

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n0jrn

XV50 Cooling

OK gang:

I've seen a number of posts in the archive about drilling holes in the
panels to cool a transverter.

None of those posts are very specific about where your drilling the holes.

Can some of you who have done this, tell me where you did that ???

OR does Elecraft make panels available that are pre-drilled ??
( I don't see then in the products list )

Just curious !

73 Jerry N0JRN

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Don Wilhelm-4

Re: XV50 Cooling

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 attenuator
resistors.

73,
Don W3FPR

n0jrn wrote:

> OK gang:
>
> I've seen a number of posts in the archive about drilling holes in the
> panels to cool a transverter.
>
> None of those posts are very specific about where your drilling the holes.
>
> Can some of you who have done this, tell me where you did that ???
>
> OR does Elecraft make panels available that are pre-drilled ??
> ( I don't see then in the products list )
>
> Just curious !
>
> 73 Jerry N0JRN
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
>

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

n0jrn

Re: XV50 Cooling

In reply to this post by 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 ([hidden email]) 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

Johnny Siu

Re： XV50 Cooling

Hello Jerry,

I am afraid that my observation with my XV50 and XV144 is different.

These transverters are extremely hot if they are run at Elecraft's advertised rated output of 10W FM and 20W SSB. The heat is from the power module and NOT the attenuator resistors.

For both XV50 and XV144, there is neither internal fan nor holes in the PCB beneath the fan area.

For XV432, there is an internal fan plus holes under the fan area. You can make reference to XV432 operation manual.

As I mentioned in my earlier emails in this forum, I need to modify my XV144 in the way similar to the fan + PCB arrangement of XV432 so as to solve the heat issue.

Of course, if you only run the XV50 at a couple of watts, there will be no heat issue. For me, I would expect the transverter should run at the advertised rated output without any heat issues but unfortunately it is not the case.

73

Johnny VR2XMC

----- 郵件原件 ----
寄件人﹕ n0jrn <[hidden email]>
收件人﹕ Elecraft <[hidden email]>
傳送日期﹕ 2010/6/3 (四) 12:58:45 AM
主題： Re: [Elecraft] XV50 Cooling

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 ([hidden email]) wrote: