For what its worth, I run a 300 watt solid state Henry repeater amp on my 6 meter repeater, its actually running at 200 watts and its been cruising along for 4 years now without a problem. I changed out the 12 VDC thermostatically controlled muffin cooling fans with 120 VAC units that come on with PTT signal and continue to run for 3 minutes after the repeater shuts down. I have zero complaints, it runs cool and quite, is clean, and proven to be rugged and reliable, for me its been a good value for the cost of the unit. If your interested contact Henry Amp directly, as they offer a good ham discount that is not reflected in their prices listed on their web site.
To the other persons comment of 200 watts seems excessive, maybe or maybe not depending on the repeaters application and transmitter location/site owner's installation requirements. Running any solid state or tube amp at full rated output generally has a detrimental effect on its life span of being able to maintain full rated output power; running an amp 1 to 1.5 dB below its rated output allows the amp to greatly increase its life span at rated output power. Factor in a dual circulator (-1 dB), six cavity duplexer (-2.8 dB), two BP cavities (-1 dB), feed line/jumper loss (-1.2 dB), total system losses -6 dB coupled with an antenna gain of +3 dB you can easily have a 100 watt PA that nets only 50 watts ERP. Running the amp at a full tilt 100 watts will likely result in the repeaters ERP being down around 40 watts after several years of operation as the PA softens over time. A 200 watt amp would give you 100 watts ERP, which under most conditions is what a 2 meter repeater gets coordinated for, unless your in a co channel or border situation that requires an ERP reduction. Running a 200 watt PA at 1 to 1.5 dB below its rated power in the installation described above would give you very close to the generally coordinated 100 watt ERP and allow the PA to have a much extended life span. Every repeater situation is different, so PA power has to be taken into account based on coordination ERP, installation requirements, available power, your budget, and antenna gain vs. coverage requirements. Good Luck, Rob K7EI -----Original Message----- From: wn1b8 [mailto:[EMAIL PROTECTED] Sent: Tuesday, November 02, 2004 12:55 PM To: [email protected] Subject: [Repeater-Builder] Re: Solid State VHF PAs My Error. It is not 200 watts but rather 100 watts. Scott --- In [email protected], Neil McKie <[EMAIL PROTECTED]> wrote: > > I can only wonder why the need for what seems to me is excessive > power? > > Thank you, > > Neil - WA6KLA > > wn1b8 wrote: > > > > Greetings, > > > > As a result of our recent power supply failure we are accessing our > > options. > > > > Thanks to all of you who have replied to my search for a TPN1041B > > power transformer. A couple of the responses suggested contacting > > Peter Dahl for a quote on repairing or replacing the failed > > transformer. I did do that and would like to report that the > > response I received (from none other than Peter, himself) was > > extremely prompt and helful. He answered all of my questions > > regardless of their simplicity or relevance. > > > > Anyway, one of the options we would like to explore is conversion to > > a solid state PA deck. So, I would like to tap the collective > > wisdom of the list and hear what brands and models people like, and > > conversely, which to avoid. This is a 2 meter repeater and its PA > > needs to be in the 200 watt range with 10 to 15 watts drive. > > > > Thanks, and 73. > > > > Scott Madison, WN1B/8 > > > > > > Yahoo! Groups Links > > > > > > > > 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/
