> Seriously, in general amplifiers need about 50 watts input to > get full legal output. That's about a 15dB max gain as set by > the FCC rules if I remember correctly.
Most 3-500 based amplifiers with 2800 V (no load) on the plates require 120 Watts or so for "legal limit" output. That's about 11 dB gain. Part 97.317(a)(2) limits the maximum gain to 15 dB (approximately 50 W drive for 1500 W out). The extra 10 to 20 watts of drive makes a difference for those who have SB-220, TL-922, AL-82, AL-1300, AL-572, etc. amplifiers. It can mean another 200+ W output. 73, ... Joe, W4TV > -----Original Message----- > From: elecraft-boun...@mailman.qth.net > [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Jack Brindle > Sent: Sunday, September 20, 2009 11:59 PM > To: -.-. --.-N3TU -.-. --.- > Cc: elecraft@mailman.qth.net > Subject: Re: [Elecraft] [K3] Will I Lose the 120 Watt Max If > I update TheSoftware? > > > Just how much power are you running? If going from 100 to 110 > makes a > 500 watt difference in the output, then you must be putting out 5000 > watts with 100 in, assuming the amplifier is linear. > > Somehow I suspect this isn't the situation... > > Seriously, in general amplifiers need about 50 watts input to > get full > legal output. That's about a 15dB max gain as set by the FCC > rules if > I remember correctly. If you need to put much more than that > in, then > you either have a lot of loss in the input coupling network (this is > intentional on some designs), or the efficiency of the finals is > really bad (old tubes?). Your strategy of getting it checked > out is a > good one. > > > On Sep 20, 2009, at 8:14 PM, -.-. --.-N3TU -.-. --.- wrote: > > > > > I'm not causing distortion and stations say it sounds clean on the > > air. I > > think I am going to get the amp looked over. Thanks for the info. > > -- > > View this message in context: > http://n2.nabble.com/Will-I-Lose-the-120-Watt-Max-If-I-update- The-Software-tp3682736p3682879.html > Sent from the [K3] mailing list archive at Nabble.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 -Jack Brindle, W6FB ======================================================================= ______________________________________________________________ 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 ______________________________________________________________ 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
