Thanks Bill, Much appreciate the information as well as the response.
I have a K3s pair, each with a P3 on one side of the station and a K1 adjacent to it. Both, of course, with power supplies. My K3s's are factory sn 10xxx units and will be here for the duration. Fascinating story on the AF front. Thanks for sharing. Stay warm, Doug W5JV Visit https://www.qrz.com/db/W5JV for some great vacuum tube finds. ________________________________ From: William Hammond <a...@me.com> Sent: Saturday, January 13, 2024 1:13 PM To: Doug Hensley <w...@hotmail.com> Cc: Elecraft List <elecraft@mailman.qth.net> Subject: Re: [Elecraft] What minimum temperature should the K station be kept at during a hard freeze Doug, You didn’t specify which “K” radio you were inquiring about. My K4D manual page 45 says: 0 C to 50 C or 32 F to 122 F. The K3s manual specifics 0-50 C for frequency stability. The K2 manual does not mention operating temperatures. The KX3 manual does not specify. I checked the non “K”, IC-7300 manual and operating range is stated as: -10 C to +60 C or +14 F to +140 F just for a sanity check. To be safe, keeping the radio above freezing is a good idea. I would think that condensation or moisture of any kind is the enemy in the cold. Storing and operating are different things. That said, I worked on a military radio that mounted in the 47 section of the B-52D, F with no environmental controls. It was subjected to 50,000‘ altitude and -50 C, F . The failure rate of that radio was much greater than the same radio that was in the pressurized and air-conditioned in a forward section of the aircraft. I might add that these radios were electrically tuned to a frequency using DC motors and heterodyned crystals (the AN/ARC-34) and it was almost always the tuning that failed. These radios were in tropical conditions in Guam or Thailand when not flying. They used sub-miniature tubes about a third the size of a miniature tube. 73, Bill-AK5X On Jan 13, 2024, at 9:22 AM, Doug Hensley <w...@hotmail.com> wrote: What minimum temperature should a K station be kept at during a hard freeze and is there a cold temperature point at which it should not be powered up? Please reply to the list and as always do not reply to a digest. Thanks in advance for any information. 73, Doug W5JV Visit https://www.qrz.com/db/W5JV for some great vacuum tube finds. ______________________________________________________________ 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 a...@me.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