Thanks Howard: Excellent information, you know what I'm trying to accomplish.
I'm aware of those tuners and thats why I thought it may be nice to have the ptt automatically disabled within the rig. There are less expensive high power tuners that don't have the features the SG-500 or Palstar has. MFJ has one also and is the least expensive of the 3. Any tuner I would use would be installed at the base of the tuner and would need to be protected from the wx. Rich - N5ZC HowardZ wrote: > When you buy the SG-500 amp, be sure to also buy the "remote on/off switch". > This remote is also your BAND SELECT switch which also has an AUTO settings. > If SGC would post a picture and description of it, I am sure they'd sell > more of them. > Considering the work it took to design and build it, I think the switch is > worth the money. > The best price is probably at R&L electronics. > > Now, you know, sooner or later you are going to forget to switch the > amplifier off before tuning. > Your auto-tuner will then fry when trying to tune with 500 to 700 watts > going through it. > (Yes the SGC 500 can develop over 700 watts - depending on the band in use) > The Palstar AT-AUTO tuner has a PTT input and PTT output - it keeps the > amplifier off both when tuning and also whenever the SWR is below the > threshhold you designate (typically somewhere between 1.5 and 2.0). The > Palstar is also rated for 1500 watts - any mode. It's expensive, but it > gets you a perfect SWR - unless your antenna really can't do it. All the > relay operated auto tuners are a compromise - they are not capable of > adding/removing small enough amounts of inductance or capacitance for a > truely perfect tune - though the relay auto tuners can be lightning fast. > > I think all the amps have self protection from high SWR. > You should have some kind of PTT automatic cutoff to protect the tuner from > high SWR while tuning. > I think only Palstar and SGC auto tuners have this protection feature. > > Howard > > > Richard Thorne wrote: > >> Kent et All: >> >> Yes thats the easy and simple way. >> >> What I was hoping for was quick band changes without the need for >> flipping switches. I'll be running an SG-500 amp and already planned on >> placing a switch in the ptt line to disable the amp. >> >> Rich - N5ZC >> >> K9ZTV wrote: >> >>> Rich . . . >>> >>> Can't comment about other amps, but running the K3 barefoot (or tuning >>> an external ATU) with the Yaesu Quadra merely requires toggling the >>> Quadra's OPERATE switch off. Toggle it back on to use the amp. >>> >>> 73, >>> >>> Kent K9ZTV >>> >>> >>> Richard Thorne wrote: >>> >>>> Is there a way to turn off the ptt signal to an amp when the TUNE button >>>> is pushed? >>>> >>>> I want to run high power but I want to disable the amp while tuning an >>>> external antenna tuner. >>>> >>> ------------------------------------------------------------------------ >>> >>> >>> No virus found in this incoming message. >>> Checked by AVG - www.avg.com >>> Version: 8.5.375 / Virus Database: 270.13.12/2233 - Release Date: >>> 07/12/09 08:20:00 >>> >>> >>> >> ______________________________________________________________ >> 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 >> >> >> > > > ------------------------------------------------------------------------ > > > No virus found in this incoming message. > Checked by AVG - www.avg.com > Version: 8.5.375 / Virus Database: 270.13.14/2238 - Release Date: 07/14/09 > 18:03:00 > > ______________________________________________________________ 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
