Outdoor antenna setup

Folks, i understand how all of this stuff works. I make my living working on, modifying and using radio communications gear. I also know that as frequency rises, ground wave transmission distance falls off. I also know that various modes of operation offer greater communications range i.e. AM transmits further than FM for the same average power levels when used on the same frequency, SSB ( single sideband ) transmits further than AM, morse code transmits further than SSB, etc... While some of you might not know it, this is the reason that morse code is used rather than voice communications in times of distress or poor conditions i.e. it has the most chance of getting through.

My business partner is going to bring in an article for me to check out written by Gordon West. He is a reknown amateur ( ham ) radio operator that does a lot of work with antennas. In this article, he is working with SSTV ( slow scan tv ) signals in the 400+ MHz range. SSTV is exactly what it sounds like i.e. a television broadcast that uses slow scan or "reduced resolution picture frames per minute". The distance that he was able to transmit a visible / audible signal at this frequency range is quite incredible according to my business partner. Given the fact that he was appr 4X higher in frequency than the commercial FM broadcast band AND transmitting video makes this even more interesting given this thread and the theories discussed in it.

For the record, we've been able to talk 100+ miles base to mobile using what is called "simplex" ( no tower mounted repeaters ) on the two meter amateur band. The two meter band primarily uses FM as a mode of communications and is 40 MHz higher in frequency than the FM radio. Obviously, this means we were using similar mode of transmission at a higher frequency making this even more difficult. The fact that we were in a "hybrid" ( big base antenna mounted up high to a little car mounted mobile antenna on the ground ) situation stresses that this type of range is quite easily obtained. Keep in mind that we were using 100 watts of power for each transmitter. Given the fact that FM radio stations use THOUSANDS of watts and both the receiving station ( your outdoor directional FM antenna ) and the transmitting tower would in effect be using "base" i.e. BIG outdoor antenna systems mounted up relatively high off the ground, i have to once again stress that this type of range should NOT be a problem. Sean
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Cdc: Does this grounding block create a signal loss?

Fyne: you do not want a plain old grounding block; you want a gas-discharge type surge supressor, similar to Tru-Spec model GRB-ARM. The grounding block will shunt any transients on the shield back to a good ground connection, but will not protect the center conductor, which is where most of the damage can occur if induced into your receiving equipment, be it a TV, a radio tuner, VCR tuner, whatever.
Yes signal losses do occur, but not so much from the protection device itself as from the two type-F connections (input & output). Expect around 0.5dB to 0.75dB typical loss through the whole arrangement, which is quite acceptable if the entire system is properly designed.

http://www.antennaperformance.com/

It's an "interesting" discussion. BIGO, given where you live, APS can probably service you directly or recommend a technician who does. BTW, the installation was not difficult for either the technician or my $pocketbook. Lots of listening pleasure from live Tanglewood Concerts this summer, and BSO in Symphony Hall in the winter. BIGO should be able to get both Boston and NYC.

Thank you all for the very informative discussion. I love this site. Len