Do they? I have a KPA500, not a '1500 but I run mine full tilt on RTTY.
Something to bear in mind in this discussion is that we run our equipment in ICAS, not CCS. Even in a contest situation we probably only transmit half the time. During the off (RX) time the amp isn't drawing any plate, collector or drain current, nor is it drawing much current on CW, key up or SSB between syllables. RTTY is a "continuous" mode without the syllabic breather, but it's still intermittent.
Wes On 8/17/2018 6:43 AM, [email protected] wrote:
So why do most RTTY users run their amps at reduced power? John KK9A From: Charlie K3ICH Date: Fri Aug 17 09:24:18 EDT 2018 I really do NOT understand why this data is so surprising. It all seems to me to be perfectly normal with the amplifier's highest efficiency occurring at near max output. Which curiously, I would assume, is the way the amp was designed. Think zero output with zero drive = zero efficiency. Apply some drive, read some output and the efficiency goes up from there. 73, Charlie k3ICH -----Original Message----- From: elecraft-bounces at mailman.qth.net <elecraft-bounces at mailman.qth.net> On Behalf Of john at kk9a.com Sent: Friday, August 17, 2018 8:57 AM To: elecraft at mailman.qth.net Cc: charles at k5ua.com Subject: [Elecraft] KPA-1500 Efficiency As A Function of Input Power Interesting data, Charles. I assumed that running the KPA1500 (or KPA500) at lower power would keep the fan from running as much. I knew that efficiency changed with output power but I did not expect that it was this significant. If your data is correct there is 1000++ watts of heat to dissipate no matter what power level you use. John KK9A ______________________________________________________________ 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]
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