How about running the exciter PTT or A+ through timed relay contacts that will open on a power failure, and then close again after sufficient time for a cold switch to be made has elapsed? The brief interruption of signal should be of little consequence to voice users, and might also serve to notify nearby users that a switch had been made.
Steve AA5SG ----- Original Message ----- From: "Paul Kelley" <[EMAIL PROTECTED]> To: <Repeater-Builder@yahoogroups.com> Sent: Saturday, November 20, 2004 8:08 AM Subject: [Repeater-Builder] GE-Moto (relay question) > > Kevin, > > That is one awesome repeater! Nice mix of GE and Motorola > stuff. I sort of have the reverse situation with GE > receiver / exciter and Moto PA. > > I have questions concerning the PA selection relays. I > assume you have relays at the PA outputs as well as the > inputs? What type of relays are you using and do you have > some means of preventing them from "hot switching" while RF > power is applied? And if not, what happens in the event of > a power failure while the machine is in use? I mean do the > relays handle it OK? > > The PA has been off my VHF repeater for some time due to a > relay problem. I need to get it back up there as we took a > major coverage hit when it failed. I want to run the tube > PA when AC power is on, but need to default to running just > the repeater / exciter (20 watts) when on battery backup. I > used coaxial relays to handle the switching but the relay > on the output of the PA self destructed (I'm guessing as a > result of not being able to handle hot switching, though I > have no proof that is what led to failure). > > I am currently trying to come up with some plan as to how to > proceed with this situation... Maybe I just need better > relays? PA output is about 200 watts. > > BTW folks, I've had several unexpected things thrown at me > lately. As a result I have been delayed on my coaxial > collinear project and photos, darn it! I will get back to > it ASAP! I expect it to be soon. > > Paul N1BUG > > > > On Friday 19 November 2004 01:53 pm, Kevin Custer wrote: > > > As promised: > > <http://www.shol.com/kuggie/ahra/hmftinfo.html> > > > > Dial Up users beware, there are several high resolution > > pictures, but they are worth the wait. > > Hi Speeders, enjoy! > > > > Comments or Questions on the GE-Moto welcome. > > > > Kevin Custer > > > > > > > Yahoo! Groups Links > > > > > > > > Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
