> va...@... wrote: > I inserted a small 20 watt PA after the TX port on our > Hamtronics REP-200 UHF machine.
Who makes the PA? 20 watts... It probably has a nominal drive value of less than 7 watts for sure... The original bare Hamtronics exciter (transmitter) is probably rated for 1.5 to maybe 2.5 watts output. Normally the repeater has an LPA (amplifier) stage inside the box and it's output is somewhere in the 12 to 25 watt range (for the basic model depending on the version). > Repeater puts out 7 watts into my Termaline after all the > filtering etc. What is "the filtering"? a duplexer? > With the amp, output is 15 watts, 3DB gain, however the > signal on the air seems weaker. You are probably over driving the extra/external amplifier. Not good... > Its not a desense issue - I can still trip it from a fair > distance - just that the transmitted signal is less with > the amp - go figure. If you looked a spectral display of the output... an over driven amplifier would not be hard to figure... you'd probably see the buckshot. If you're receiver doesn't seem to suffer, you're probably getting lucky. > The repeater is now at my house temporarily, so conditions > are not ideal for height etc. For you, the repeater or the antenna? :-) > Any ideas? Marry someone with a lot of money... Seriously, give us more information about what each item is and it's power level. We'll give you some ides. Chances are you're probably over driving an external amplifier. If you'd like to use the amp... there are ways to reduce the drive level without grief. > Also, if anyone has a nice 75-100 watt UHF PA around, for a > reasonable price....well you know the rest. You would experience serious trouble placing that size amplifier on your stock repeater without mucho extra protection in/on both the receiver and transmitter side (not to mention the duplexer). > Cheerio > Ian > VA2IR Raisin Brand... :-) s.
