The reason is because then it does sometimes get up to level 5 and I prefer to keep it below that, if using level 3 as the minimum happens to accomplish that. Level 4 with headphones on is fine, level 5 is just a tad too noticeable.
My only type of operation is CW, no monologues, sometimes as much as two or three minutes at a time, maybe as long as 5 minutes, full qsk with "back and forth" conversation. When I leave it on NOR, invariably on the longer transmissions it will eventually get up to level 5. When I set the minimum to level 3, it never gets above 4. We typically are running QRQ (e.g. 60-65 wpm) but the duty cycle is the same as at 30 wpm of course, and the fan does the same thing at those speeds. No high SWR, the amp never sees more than 1.5:1, using the KAT500. As for temps: Testing in a dummy load with a continuous 60 wpm CW canned message, 400W out, starting with fan off (NOR): Start: 36C 11 secs: 40C 50 secs: 50C 2.5 mins: 60C 4.5 mins: 65C In this test it leveled off at 65C, never kicked up to level 5. Room ambient is 79F. I would guess this rate of temperature rise is probably normal. But since it sometimes kicks up to level 5, when it has started from off, and never does when I keep the minimum at level 3, I prefer that. I would guess for the several minutes at a time when I am listening, it cools back down further with level 3 than with level 0, don't really know. My daily sked has had his amp for a year or more and he experiences the same behavior, he also leaves his at level 3 for the same reason. Chuck, W5UXH AG0N-3055 wrote > But why not let the thermostatic controller do its thing? And, if it is > kicking up to high speed in a QSO, you must be doing some very high duty > cycle QSOs, i.e. talking continuously or working AM with long > transmissions. Temps will run higher if you are > running some reflected power too. > > Gary > -- -- View this message in context: http://elecraft.365791.n2.nabble.com/KPA500-Fan-Control-from-KPA500-Utility-tp7579971p7579981.html Sent from the Elecraft mailing list archive at Nabble.com. ______________________________________________________________ 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
