Thanks for that. I never understood the Ameritron ALC instruction for my ALS-600 so I just never used the ALC. That attached instruction was much clearer and made sense.
Brian Denley KB1VBF Sent from my iPad > On Feb 28, 2019, at 10:19 PM, Bob McGraw K4TAX <rmcg...@blomand.net> wrote: > > This fellow seems to have a good handle on the ALC issue as it relates to > overshoot in the transceiver. > > https://www.w8ji.com/alc_exciter_power_overshoot.htm > > > Here Tom goes into the discussion of good ALC vs. bad ALC systems. > > https://www.w8ji.com/ameritron_alc_adjustment.htm > > > 73 > Bob, K4TAX > > > >> On 2/28/2019 8:51 PM, K9MA wrote: >> Many years ago, I built a tube amplifier with what I thought was a fairly >> sophisticated ALC circuit. I could never get the ALC loop to be stable. I >> know a lot more about control systems now, but I still don't know how to get >> ALC around an amplifier to work, and apparently neither does anyone else. >> What I don't understand is why it's so hard with an external amplifier, as >> every transmitter has ALC for its internal 100 W amplifier, and that works >> fine. Why the same design doesn't work with an external amplifier is the >> mystery. >> >> The problem with just limiting the drive power and using the transmitter's >> ALC is that, especially for solid state amplifiers, the required drive power >> can vary considerably with SWR and temperature. That requires either riding >> the power control continuously or running your amplifier well below rated >> output most of the time. (Unless, of course, you're running a 2.5 kW >> amplifier, but that kind of margin is expensive.) So, if anyone could figure >> out how to get ALC to really work with an amplifier, I think that would be >> worth paying extra for. >> >> 73, >> Scott K9MA >> > > ______________________________________________________________ > 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
