[Elecraft] Re： XV50 cooling

[Don Wilhelm]

Johnny,

Prior to testing, I have reviewed the datasheet for the RA30H0608M 
module that is used in the XV50.  The power module is specified to 
operate within spec at 110 degrees C ( 230 deg F).  While that is too 
hot to touch (in excess of boiling water temperatures), it is well 
within the device specifications.
I am looking at the Mitsubishi data sheet for the RA30H0608M device.

I will see what my tests reveal, but I believe the answer will be that 
the temperature is well within the device specifications.

The MTBF for the device is not specified in the datasheet, but it ia a 
well known fact that the MTBF for any device decreases with the 
operating temperature.  So the early answer is that the output module 
will likely operate within its specified temperature range, its 
longevity might be extended by providing extra cooling to reduce its 
operating temperature.

Testing will reveal the actual temperature rise - details later.

73,
Don W3FPR

Johnny Siu wrote:
> Hello Don,
>
> The situation is - after I operate either XV144 or XV50 for a 10-15 minutes QSO under 10w FM or 20 w SSB (the advertised rated output from Elecraft, p.3 of the owner's manual), the bottom plate (or even one of side panels) is too hot to be touched.  
>
> I would be very interested in your findings and fully appreciate your knowledge of Elecraft products. After your test, I would be grateful if you could advise, it is all ok to operate the XV50 / XV144 under Elecraft's rated output WITHOUT the need of any modifications to remedy the heat issues.
>
> It would be of great assistance if you could give your advice about the maximum length of any QSO under the rated output.  In other words, say for example, I should not use the XV50 / XV144 for any QSO longer than 15 minutes.  Or, there should be 5 minutes cooling time between each 15 minutes QSO etc.
>
> Thanks a lot in advance and look forward to your results.
>
> 73
>
> Johnny VR2XMC
>
>
>
> ----- 郵件原件 ----
> 寄件人﹕ Don Wilhelm <w3fpr at embarqmail.com>
> 收件人﹕ Eric <gliderboy1955 at yahoo.com>
> 副本(CC) "Elecraft at mailman.qth.net" <Elecraft at mailman.qth.net>
> 傳送日期﹕ 2010/6/4 (五) 7:18:59 AM
> 主題： Re: [Elecraft] XV50 cooling
>
> Eric,
>
> Have you actually measured the temperature rise?  I am interested in 
> just how much is "excessively hot".
> While it does get warm, I have always found the temperatures to be well 
> within spec for the output module.
>
> I have an XV50 here for repair right now.  It is next in line for work, 
> and I intend to get to it this weekend.  After it is repaired, I will 
> measure the temperature rise on the bottom panel right under the heat 
> spreader.  I have a Fluke 279 with a temperature probe available.
>
> Report on Monday.
>
> 73,
> Don W3FPR
>
> Eric wrote:
>   
>> I have a late-model xv144 with holes in both top and bottom panels, connected to k3 with milliwatt drive. It runs excessively hot at 10w out in digital mode EME when used one minute on one minute off,  so i dont think  just getting new panels will help you.  I use a small muffin fan blowing air underneath with the xv-144 up on the optional tilt stand and this simple solution works great. 
>>
>> I also use an xv-432 for eme at 10w but its internal fan keeps it cool. 
>>
>> Perhaps if enough people request a retrofit kit with an internal fan for the xv-50 and xv-144 Elecraft would consider it.  I'd pony up. The fan could attach inside the top panel. 
>>
>> 73
>>
>> Eric WD6DBM 
>>
>>   
>>     
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