FT8 is a weak signal mode. That does not always equate to low power. I have seen many instances on 6M where 400 watts resulted in a -15 signal report from the far end.
Many of the K1JT modes started with moon bounce where it often took 1500 watts to get a weak signal back. Very 73 - Mike - K9JRI > On Jul 17, 2018, at 10:15 AM, turnbull <[email protected]> wrote: > > I thought FT8 was a low power mode. Am I wrong? I am not referring to Fox > Hound mode. > > 73 DOUG EI2CN > > > > Sent from my Samsung Galaxy smartphone. > > -------- Original message -------- > From: Michael Blake via Elecraft <[email protected]> > Date: 17/07/2018 14:12 (GMT+00:00) > To: Nr4c <[email protected]> > Cc: Elecraft Reflector <[email protected]>, ANDY DURBIN > <[email protected]> > Subject: Re: [Elecraft] KPA500 thermal clicks > > While possibly my imagination, after a few months of use I loosened all of > the Z bracket to heatsink screws and side panel to heatsink screws and then > retightened all of them plus the top cover to Z bracket screws. That seemed > to reduce the clicking. > > Very 73 - Mike - K9JRI > > > > > > On Jul 17, 2018, at 9:05 AM, Nr4c <[email protected]> wrote: > > > > “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] > > ______________________________________________________________ > 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]
