Tube amp just has the single fan that doesn't spin at 9000 rpm like the little solid state fans, hi. Same noise level if xmit or not. BillK3WJV
On Friday, June 1, 2018, 9:04:45 PM EDT, Dr. William J. Schmidt <b...@wjschmidt.com> wrote: So just a bit of thermodynamics... if the input to any amplifier is 1500 watts and it is 50% efficient, since energy is conserved, 750 watts will come out in another form.. and in this case it's heat. Doesn't matter what the converter is (transistor, tube, resistor, etc.). It all behaves the same. Need to get rid of 750 watts of heat. The only difference may be the way the heat is taken away of the converter... convection (heat sink), forced convection (heat skin plus fan), liquid convection (water cooled heat sink). The poison is the heat removal device not the converter. Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois Owner – Operator Villa Grand Piton – J68HZ Soufriere, St. Lucia W.I. Rent it: www.VillaGrandPiton.com Like us on Facebook! Moderator – North American QRO Group at Groups.IO. email: b...@wjschmidt.com -----Original Message----- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Bill Stravinsky via Elecraft Sent: Friday, June 1, 2018 7:33 PM To: Elecraft Reflector <elecraft@mailman.qth.net> Subject: Re: [Elecraft] KPA-1500 Fan Noise - YouTube ? Rich You pretty much hit the nail on the head about solid state amps. As they say there's no free lunch. Solid state has made great strides in high power ampsbut its still solid state and a p/n junction or some form thereof. 1500 watts of heat in those junctions has to be cooled down or it won't be long before it needsnew parts. Depending on your operating habits (contesting, casual, or whatever) there will be varying degrees of fan noise. The higher the duty cycle the higher thefan requirements. Pick your poison, a small light weight amp easy to move around or one you need a fork lift to pick up. I prefer tube amps for a few reasonsand have the Acom 2000a (and an Alpha 89 that now sits in the living room temporarily) but I'm still glad I got the kpa1500 at least so far. The kpa sits nicely on top of the Acom without causing the table they sit on to crash to the floor in pieces, hi. I'm surprised nobody has made a you tube ofthe amp in operation actually. But there are only just over 200 of the new amps out there. Good luck with your investigation, Rich. BillK3WJV On Friday, June 1, 2018, 8:00:29 PM EDT, Richard Thorne <rtho...@rthorne.net> wrote: This fan noise issue has me concerned to the point that I’m considering cancelling my order. While the amp won’t be on my operating desk, it will be on a rack next to my operating desk. Remoting the amp is not an option. Quite frankly I have no interest in remoting the amp. Is there anyone out there that has a KPA-1500 willing to post a YouTube video so we can hear the fan in action and judge the noise for ourselves? From the research I’ve done it appears that if you want a solid state amp, regardless of make, you need to be prepared for fan noise. Thanks Rich - N5ZC Sent from my iPhone ______________________________________________________________ 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 k3...@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 b...@wjschmidt.com --- This email has been checked for viruses by AVG. https://www.avg.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 k3...@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