Supposedly this would be license exam reference material, that AM signals can vary instantaneously from nothing at full negative modulation, to four times the carrier power at full positive modulation. Therefore AM PEP is four times carrier power at full modulation.
QRO limit today would be 1500/4 or 375 watts carrier output. My 3-1000Z needs 55 watts input PEP for 1500 PEP out. 55/4 is 13.75 watts carrier to drive my Z box to today's legal limit AM signal. The AM PEP value will always be the limiting factor in a string of linear amplifiers, just as in SSB. This stuff in the USA question pools? If it isn't required for a license, maybe it ought to be in the manual. In pre-1.5kw days the carrier INPUT power allowed was 1000 watts, usually class C with plate modulation therefore putting out 750 watts of carrier PLUS full modulation which meant those old Johnson desk kilowatt rigs were putting out 750 watts carrier and 3KW PEP at high modulation. On Sat, Jun 19, 2010 at 6:15 PM, Radio Amateur N5GE <[email protected]> wrote: > On Sat, 19 Jun 2010 17:06:57 -0500, Grant Youngman <[email protected]> wrote: > > Thanks Grant! I wonder why they don't say something about that in the > manual?... > > Tom, N5GE > Licensed since 1976 > QCWA Life Member 35102 > > [email protected] > http://www.n5ge.com > http://www.swotrc.net > >>The K3 automatically sets the correct carrier output level for AM -- approx. >>1/4 the set carrier power. Fiddling is really not required. >> >>The proper way to use the radio into an amp, for example, is put the radio >>in "tune", adjust the K3 output tand tune the amp to the desired PEP output >>level. (And heavily load the amp, the the way). When you key up in AM, the >>K3 drops the carrier to 1/4 the set power, which is the correct level. >> >>The power rating on AM is by definition 100W PEP -- the same as SSB. >> >>Grant/NQ5T >> >> >>On Jun 19, 2010, at 4:37 PM, Radio Amateur N5GE wrote: >> >>> On Sat, 19 Jun 2010 16:37:32 +0000, Jim Harris <[email protected]> wrote: >>> >>> Interesting, Jim. I did a search of the PDF Owner's Manual and came up with >>> zilch regarding AM transmit power suggestions or adjustments. That must be >>> an >>> oversight. > [snip] > > ______________________________________________________________ > 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 > ______________________________________________________________ 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
