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What happend to the K5IN 440.500? I do not hear it on the air.

Moved from Capitol to Buck, but got clobbered by 444.300, and then the PA lost its PSU connection...
So Brian went back up the hill last Friday and put the 441.950 back in the Buck cabinet but kept the Angle Linear preamp and bandpass filter... Sometime soon I imagine it will be reinstalled back up on Capitol, but likely will run the ARR preamp pulled off of Buck. I notice the 441.950 hears better than the 444.3 at least from my location, but that may be due to the antenna type and pattern, in addition to the better-spec preamp :wink:

Eric
KB7DQH

_________________
That is how the people at DARPA think. they take things and use them in unconventional ways, to see what happens.

Maybe a cavity can be put in series with 440.500 so it can be kept on buck? Was the site rent at getting alittle to pricey and encouraged the move?

You may have noticed that all the K5IN 222 machines remain at both sites :mrgreen:

Switching
the frequencies was done to try and rid the UHF repeaters of a frequency-hopping spread-spectrum
system DOD is using in the area... to no avail.

The desense experienced by the 440.5 machine on Buck (from the 444.3 transmitter in the same building) was such that 40dB of notch likely would have not been enough to avoid the interference, so the decision was made to "put Buck Mt. back the way it was" (441.950) with the exception of using a hotter preamp there...

Initially the design criteria for the UHF on Buck was as a "linking" machine and therefore didn't need a whole lot of RX sensitivity or output power as the "important" radios "working" it were on mountaintops, but it worked so well as a general purpose UHF machine in its own right, that it was "upgraded"...

The other issue was the link radio/antenna combination on the N7IPB machine on Lyman was at times having difficulty putting a decent signal into Buck for some reason, mostly during disturbances in the Troposphere associated with weather fronts and morning/evening enhancement-- which would knock out the path from Lyman to Buck, but due to the 5 Mhz frequency separation, never the other way around... so improving the RX at Buck would tend to improve the robustness of the link radio paths from Capitol and Lyman...

At some point when Brian "gets around tuit" 440.5 will be reinstalled on Capitol Peak... and when N7IPB "gets around tuit" a repositioning of the link antenna (higher up the tower) and a more powerful link radio will be installed there... and then the "system" (fingers crossed) will "live happily ever after" :mrgreen: :mrgreen: :lol:

Eric
KB7DQH

_________________
That is how the people at DARPA think. they take things and use them in unconventional ways, to see what happens.