Personally, I wish Elecraft offered a slightly different approach, rather than a minimum fan speed setting, how about a RX minimum and TX minimum? This would allow quiet operation on RX, but would anticipate a higher demand for cooling on TX.
There is quite a bit of thermal mass and overshoot that happens in TX on digital modes. By the time the fan turns on, it tends to be running behind the curve trying to catch up. Starting the fan running as soon as the rig goes into TX would help considerably and allow things to go back to quiet in RX. 73, Bob, WB4SON On Tue, Oct 1, 2019 at 4:58 PM Bob McGraw K4TAX <rmcg...@blomand.net> wrote: > For SSB voice operation and CW operation I leave the fan speed at > NORMAL. For digital modes, which all have a higher duty cycle, I > usually set the fan speed to 1. I do find the fan speed increments up > and down as needed and as driven by the temperature. When running 400 > to 500 watts most of the time for digital modes, I occasionally see 60 > degrees. The fan speed at 1 does not elevate the room noise at all. > In fact, I don't hear it, although I do have sound damping material on > the wall immediately behind the equipment. Usually something in the > house or shack is making more noise. > > As to if setting the fan speed to 1 for digital modes, it seems to keep > the amp temperatures overall a bit lower. No scientific study conducted. > > 73 > > Bob, K4TAX > > On 10/1/2019 11:51 AM, Andy Durbin wrote: > > Thanks to everyone who contributed their experience of operating with > min fan speed set above 0. > > > > I have some ideas for a test series and I'll share anything I learn from > it. > > > > Here is a teaser for those interested in KPA500 thermal management. Did > you know that, for a KPA500 that has not transmitted for a long time, the Z > bracket is hotter than the heat sink and the heat sink is hotter than the > finals. For that condition the heat flow is from the Z bracket, into the > heat sink, and then it heats the finals. The heat flow reversed during TX > as the finals heat up. > > > > 73, > > Andy, k3wyc > > ______________________________________________________________ > > Elecraft mailing list > > Home: http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/mmfaq.htm > > Post: mailto:Elecraft@mailman.qth.net > > > > This list hosted by: http://www.qsl.net > > Please help support this email list: http://www.qsl.net/donate.html > > Message delivered to rmcg...@blomand.net > > > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to wb4...@gmail.com ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
