Hi Don, Ordinarily, the W6PQL amp’s control board does this via ALC on the exciter. But, since that is not an option with the K3S, setting TX DELAY on the K3S to 20 milliseconds should do the trick. That is what Jim, W6PQL, suggested I do.
I have been using the W6PQL amp with the K3S without any problems heretofore. 73, John WA1EAZ > On Sep 23, 2018, at 12:17 PM, Don Wilhelm <donw...@embarqmail.com> wrote: > > John, > > There is TX Inhibit that will prevent RF from the K3 until that signal is > dropped. > Of course, it requires a signal from the amplifier or sequencer to indicate > that it is ready for RF. > > Trying to use ALC for that purpose is not a good idea. > Does the amplifier control the high on ALC, or is that left to the exciter to > implement? > > 73, > Don W3FPR > > On 9/23/2018 11:29 AM, John Stengrevics wrote: >> Hi Don, >> >> That was timely as I just got off Skype with Jim, W6PQL. He mentioned that >> the ALC should be held high for some milliseconds to allow for the amp’s >> relays to switch over thereby protecting the LNA. >> >> Since the K3S works differently than most, he suggested that I look for an >> RF Hold-Off setting on the K3S and set it for around 50 milliseconds. That >> being said, I don’t see that in the manual or in Fred’s book. Any >> suggestions? >> >> 73, >> >> John >> WA1EAZ >> >>> On Sep 23, 2018, at 11:12 AM, Don Wilhelm <donw...@embarqmail.com> wrote: >>> >>> John, >>> >>> I do not understand how the amplifier or the ALC could protect the LNA. >>> I assume the LNA is only used on receive, so if you have good sequencing >>> between receive and transmit, no damage could occur. >>> ALC is only applicable to transmit, and Elecraft does not recommend using >>> ALC to limit the drive to the amplifier. Set the power to the amp properly >>> and all will be well. >>> Using ALC to control the exciter power is a bad way to do things, it will >>> only lead to distortion and spurious emissions from the amplifier. >>> >>> 73, >>> Don W3FPR >>> >>> On 9/23/2018 10:58 AM, John Stengrevics wrote: >>>> My apologies - I should have added that I am using a Downeast Microwave >>>> DTR relay to take the LNA out of the line when voltage applied to the >>>> relay drops as a result of transmission. >> > ______________________________________________________________ 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
