7 Watt Moseley radios On Feb 17, 2016 11:56 AM, "Adam Moffett" <[email protected]> wrote:
> How much tx power are they allowed to use on that STL? 30 watts? More > than what's allowed in part15 in any case. > I don't doubt that it worked for them. I only doubt that it will work for > a WISP. > > > On 2/17/2016 1:46 PM, Jaime Solorza wrote: > > Clear Channel engineers and my guys installed two 942.xxx MHz passive > repeaters using 24 or 26 dB large grid antennas for STL when moving from > one side of city to other over Franklin's. Used 1 1/2 inch heliax....2 > miles to mountain on one side and under a mile at other side. I shared > those pictures years ago and some even made fun of me for sharing them so > much on different topics. We did allot of work for them. > On Feb 17, 2016 11:32 AM, "Adam Moffett" <[email protected]> wrote: > >> Exactly. Use an online freespace path loss calculator. >> In real life, I've yet to encounter a scenario where the math actually >> worked. >> >> Suppose the barn is 5 miles from the tower, and 100 yards from the >> customer's office. >> Using the calculator at https://www.pasternack.com/t-calculator-fspl.aspx >> : >> 100 yards (customer to barn) = -87db FSPL >> 5 miles (tower to barn) = -126db FSPL >> sector antenna gain (tower) = +16dbi >> 2' dish gain (barn1) = +28dbi >> 2' dish gain (barn2) = +28dbi >> 2' dish gain (customer office) +28dbi >> tx power from tower = +26dbm >> >> That adds up to an RSSI of -87dbm assuming everything else is perfect. >> So you've got a lot invested to get a signal they won't be happy with. >> >> If it were 900mhz >> 100 yards = -71 db >> 5 miles = -110 db >> Let's say yagi antennas x 4 at +15dbi each for a total of +60 >> Tx power at +21 (to be legal). >> >> That adds up to -100dbm. Doesn't work at all. >> >> So really, you need one path to be short and the other to be *extremely* >> short. >> >> >> >> On 2/17/2016 1:11 PM, Ken Hohhof wrote: >> >> When this has been discussed before, it only works if one path is really >> short. You add the antenna gains and the free space loss of both paths. >> If both legs have FSL on the order of 100 dB, you are not going to make it >> up with antenna gain. >> >> The huge billboard style passive reflectors are a different matter. >> >> >> *From:* That One Guy /sarcasm <[email protected]> >> *Sent:* Wednesday, February 17, 2016 11:40 AM >> *To:* [email protected] >> *Subject:* [AFMUG] passive relay >> >> We have a bunch of old 2' radiowaves dishes laying around. >> >> Im curious what the real world loss would be if we used them on a >> midpoint with the feedhorns patched together. >> >> Like for a business buried in trees that has an old tall barn with no >> power but line of site to our PoP. this is a really common occurrence. All >> we would need to do is get the feedhorns replaced with dual pol horns. >> >> This is on my list of things I would like to set up here shooting around >> the corner of our building out of curiosity, but I never have time to play >> with it >> >> -- >> If you only see yourself as part of the team but you don't see your team >> as part of yourself you have already failed as part of the team. >> >> >> >
