Hi Eric, I've read about the issue with turning down a 110 Watt PS in many places. All it always mentions is possible spurious emissions. The fact that the output impedance changes never occured to me. That certainly could explain what I have been experiencing. I did check the output of the transmitter with a lab grade (but not recently calibrated) spectum analyzer. The PA did not produce anything but the desired carrier down to nearly 0 output into a dummy load. So I thought I was in the clear.
I will tune the PA to the power levels indicated in the manual and do the comaprison between antenna and dummy load (no duplexer). If this resolves the problem it would prove that idea. BTW, the reason for choosing the 110W radio over the 50W radio is the size of the heatsink. I had hoped that the 110W PA turned to 50-75% power would have much better heat characteristics. Once I actually tuned the radio it turned out that the reduction in PA output power does not mean an equivalent reduction in current draw. Adi On Sun, 4 Jan 2004, Eric Lemmon wrote: > It seems that your "problems" began when you changed the output power of > the radio. As has been mentioned many times in this and other threads, > the output impedance of MOST solid-state PAs will change radically when > the drive level is not at the factory-specified value. So, yes- you > have an impedance mismatch problem. 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/
