Water cooling is OK for QRP. A friend of mine was building a "special" contest amplifier. He was working out the cooling which presented a problem because of the heat involved. I suggested using an upright type freezer and put amp in the freezer, It worked great!! George, fritkin
On Sunday, December 14, 2014 3:55 PM, Mel Farrer via Elecraft <elecraft@mailman.qth.net> wrote: Good point David, I have seen an industrial RF amplifier heat sink made out of a 1/4 " copper plate married to a aluminum water cooled plate. Ran on a simple 120 VAC pump to a 5 gal tank, like my 5KW Bird water cooled dummy load that uses a total water waste system does the same dissipation. As I remember, many years ago, it was rated at removing 5KW of heat. I know should have the BTU but I don't remember. Mel, K6KBE From: David Cutter <d.cut...@ntlworld.com> To: elecraft@mailman.qth.net Sent: Sunday, December 14, 2014 3:32 PM Subject: Re: [Elecraft] LDMOS for QRO [OT] I'm a little surprised that folks in this group haven't suggested liquid cooling for this modest application. Semiconductor cold plates have been around for a long time, are economical to use and in my view a much better solution than forced air cooling. They are compact, quiet, require far less cabinet space, keep junctions cooler and more stable than air could ever and enable higher reliability. Look at Aavid for instance, whose devices I used on many occasions: http://www.aavid.com/sites/default/files/products/liquid/pdf/liquid-cold-plate-datasheet-hicontact.pdf If you play your cards right, you can cool the amplifier and the power supply on a short 4-pass plate. Put the heat somewhere convenient, not in your shack. 73 David G3UNA ______________________________________________________________ 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 farrerfo...@yahoo.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 georgefrit...@yahoo.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