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 <[email protected]> > 收件人﹕ Eric <[email protected]> > 副本(CC) "[email protected]" <[email protected]> > 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 >> >> >> > > > > > > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
