On Jun 13, 2008, at 11:53 PM, Daron Wilson wrote: > >If multipath is your problem, then more power is probably not going > to > help. > > My point was simply that a change in the repeater transmitter from > 25 to 50 > watts is 3dB, that is a stronger signal in the field. Multipath is > not the > only problem, and maybe not even a clear explanation of the problem. > Essentially anything in the signal that disrupts that stream of bits > hoses > the signal. Good ole mobile picket fencing, static, fading signal, > etc. all > are death to the digital signal. >
You think 1/2 of an S-Unit is going to fix those things? > If you can't make an amplifier work in your setup, or feel you don't > need, > that's fine with me. However, if adding one in MY situation makes > the range > of the repeater increase or the BER of the signal drop at more > distant fixed > stations, then it helps my situation. > Agreed, but I'm challenging you (not heavily -- do what you want, of course... it's only ham radio) to prove that 1/2 of an S-Unit makes a *significant* coverage difference, all other things being equal. (It won't on digital. It would for a large area where there's about 17dB of degradation in analog before you hit the 12 dB SINAD point on the curve, there's almost no "curve" to digital -- see N5RFX's article and measurements in the recent TAPR Journal.) > Your mileage may vary. > Already has! (GRIN) Working the repeater 92 miles away with a standard mobile setup here on Medium power (15W) on UHF on the ID-800H today. It won't work that way with multipath, but there was visible "picket fencing" of the signal strength meter all the way out here, and numerous transmissions in the conversation back and forth between me and another user, while me ID-800H showed zero bars of signal strength. The receiving station heard no perceived difference in my signal. It's digital, and analog system design applies as far as professional quality installation, and equipment, and knowing where to spend money (antenna) for the biggest bang for the buck, but the coverage desires/ design aspects are completely different than what hams are used to in analog repeaters... Accessing an analog system on that mountain from here is annoying at best, unusable at worst. The D-STAR system, no one can even tell that I'm 90+ miles out. And I can hear the 20W repeater (16W out of the duplexer) 100%, including data/callsigns, perfectly. -- Nate Duehr, WY0X [EMAIL PROTECTED]
