"“Clicks” caused by the “Z” bracket are well documented and normal. Personally, I don’t find this “intolerable” or even slightly annoying. My wall clock “ticks” every second. "
I'd appreciate a pointer to any discussions of Z bracket clicks. My search didn't find anything. I have 2 clocks on the wall they tick every second. My brain is able to completely tune them out. The thermal clicks are *much* louder than my clocks and are not regular. My brain locks in on them immediately. 73, Andy k3wyc ________________________________ From: Nr4c <[email protected]> Sent: Tuesday, July 17, 2018 6:05 AM To: ANDY DURBIN Cc: [email protected] Subject: Re: [Elecraft] KPA500 thermal clicks “Clicks” caused by the “Z” bracket are well documented and normal. Personally, I don’t find this “intolerable” or even slightly annoying. My wall clock “ticks” every second. Sent from my iPhone ...nr4c. bill > On Jul 17, 2018, at 7:56 AM, ANDY DURBIN <[email protected]> wrote: > > The clicking of my KPA500 is almost intolerable and I'd like to know if what > I'm experiencing is typical. > > > In an FT8 TX/RX cycle with output power 126 W my KPA500 clicks 7-8 times > during 15 second transmit and 7-8 times during 15 second receive. In these > TX/RX cycles my logger shows the finals temperature swings between 57 deg C > and 63 deg C. During this test the KPA500 was seeing an SWR of 1.02:1 and > calculated PA dissipation was 307 W. > > > I don't think this temperature swing is likely to cause the heat sink to > expand and contract significantly. The thermal mass of the heat sink is > quite large and the heating and cooling periods are short. The first click > happens almost as soon as the KPA500 is keyed. > > > I think it is possible that the clicks are caused by expansion and > contraction of the finals at their mounting points. Is that likely and, if > so, why would it be considered normal? > > > 73, > > Andy k3wyc > ______________________________________________________________ > 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 > Message delivered to [email protected] ______________________________________________________________ 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 Message delivered to [email protected]
