poledo said:
... what's the tallest tower in Pensacola that would make a viable location for translators? I assume the best coverage they could dream of for 250 watts would extend from Cantonment to Milton to Navarre to Perdido Key (I'm assuming Gulf Shores wouldn't be possible, no towers in SW Pensacola due to NAS Pensacola)
poledo, you put forth some interesting locations for a translator to be placed. I did some "simple circle" plots with a map program using the FCC provided data for some other translators in the area that are authorized 250 watts at various heights. The perfect "test subject" as it were is literally in my back yard: WHEP's 250 watt translator, which runs at 282 feet AGL in a perfectly flat part of the area. Their 60 dBu radius is 6.7 miles. 282 feet above ground is a realistic number for a translator in the Pensacola area, although the HAAT would be much different since P'cola has some hills. Still, it's a great ballpark figure to plot on a map. Caveat emptor:
I'm not an engineer, I don't have any plotting software or complex slide-rule equations to fuzz out or anything. This is just idle speculation from a doofus.
One thing I think is not important (and remember, I'm not an engineer) for translators is height in this part of the country. Skip being the problem it is, I think the power needs to stay low to the ground as much as possible. The area doesn't boast any towers over 1,000 feet that I know of, anyway, and if it did, putting 250 watts that high up would probably kill the entire signal during tropo. We're dealing with much lower signal levels off the bat versus the big sticks in Baldwin County.
One thing that's for certain. Unless someone can find me a tower south of I-10 that's over 1,000 feet AGL, I don't think you're going to find any possible site that would put a 60 dBu signal over both Milton and Perdido Key, or both Cantonment and Navarre. But there is one good "compromise" point…
poledo said:
-There's the WRRX tower on Fairfield Dr. near the Escambia county (FL) jail. that would be perfect for Pensacola and could cover Pensacola Beach and Perdido Key but it's probably too short to cover Navarre, Pace, and Milton. I assume this is the most likely location.
A 250 watt translator at 282 feet (which would be about halfway up that WRRX tower) would give about a 6.7 mile radius for the 60 dBu contour.
See this
graphic for an idea of the coverage for a translator here. The guesstimated 60 dBu circle is in red.
poledo said:
-I know nothing about the height and location of the towers the religions non-comms are on in Pensacola and Pace... but they must be on towers taller than typical cell phone towers.
They're taller, but not by much
! I also checked out WTGF's tower in Pace (246 feet), WEGS's tower in Milton (440 feet) and WKFP's tower near Eglin (282 feet). None of them would allow good coverage of Pensacola with just 250 watts and would also not fit the AM on FX rule (more on this later).
poledo said:
-The two towers in Midway near the Gulf Breeze Zoo (home of WUWF-FM, WPAN-TV and Calvary Chapel's translator) would cover Pensacola (line of site path across water) and Navarre well, but could it reach Pace, Milton, or Perdido Key? Since they built two of the areas tallest towers here, it suggest that it's the best location available, but those towers were built to cover Pensacola with secondary coverage of Destin, Destin coverage would not be possible with a 250 watt translator... The original CP for WRRX put it on one of these towers, but it went on the air from the tower near the Jail. I assume that was the best location for building penetration in Pensacola with the 6kw signal.
I think you're right about that. 6 kW close up does a lot better than 25 kW far out. I think the same applies to 250 watts or less. Put it low down by the radio. It rhymes
! 
250 watts from here would be a non-starter, even if it could be mounted at the top with WUWF. The 60 dBu contour, where most radios would have to do their listening, doesn't even reach Gulf Breeze from that site.
Here's an overview
graphic of all the sites mentioned and plotted for basic 60 dBu coverage. Here's the key:
The RED circle is from the WRRX tower at Fairfield near Pace. 250 watts at about 282 feet.
The BLUE circle is from the short WTGF tower in near Pace. Also 250 watts at 282 feet. That's impossible, of course, since the tower is only about 240 feet tall. It's seriously short if you see it in person!
The GREEN circle is for the WEGS tower closer to Milton, but with 250 watts at about 440 feet. Neither WTGF or WEGS are suitable for Pensacola coverage with a translator, unless there's a
really big height difference at work somewhere in the terrain.
The ORANGE circle is for 250 watts at ~560 feet from the WUWF tower, which itself is only 617 feet or so. It's a massive area for a translator but no primary Pensacola coverage. Depending on secondary coverage would be do-able, but sketchy on most radios IMHO. It'd be fine if the station were Navarre-centric, though.
Finally the far-out one in PURPLE is the WKPF K-Love tower near Eglin. Not even a contender. That just leaves…
poledo said:
-The old 107.3 tower in Cantonment must be the tallest? Does Clear Channel own it? Would CC be willing to lease space to the competition? Could 250 watts reach Gulf Breeze and Pensacola Beach from here? It definitely couldn't reach Navarre, or could it? I always wondered why WRRX wasn't on this tower as it's much taller than the one near the Jail.
I don't know if CC owns the tower, but they have a licensed auxiliary site there with 8.5 kW at 1407 feet HAAT. Since there are some translators up around Birmingham that are on tall towers, I picked the one with the greatest distance to the 60 dBu I could find, which was actually one on a shorter stick but with the full 250 watts: 13.7 miles. Unfortunately, even at that height the 60 dBu would fail to cover the city of Pensacola at all, and would only hit the I-10/US-90 exit west of town. It's a (relatively) big signal on paper but covering mostly cows and trees.
There are also some LPTV towers that might be suitable, such as WBQP-LP's tower between W and 29. A translator there would do a fine job of covering much of the city, but it still wouldn't reach the NAS or Cantonment or Pace or Gulf Breeze with a strong signal.
One thing that we haven't touched on yet is the rule for translators relaying an AM signal. This is where it gets tricky. The rule is the 60 dBu contour can't exceed either a) 25 miles from the AM tower site or b) the 2 mV/m daytime contour, whichever is closer.
This would knock out
ALL the religious sticks in town and most of the LPTV towers. The WRRX site
might be do-able at full power but it would be a very close call. A translator relaying WBSR from that site might not get to use the full 250 watts. In fact, the 2 mV/m rule kills any really fanciful notions of covering the entire metro, anyway. Look at WBSR on
Radio-Locator. The red circle is ~2.5 mV/m. It's a tiny area.
Now
after all this, where do I think they should stick the translator?
On the AM tower they already own!
Think about this. The AM tower is centrally located on Pace Blvd. It's 252 feet tall. A small FM antenna mounted at or near the top would be about 240 feet HAAT. That would be about 6.25-6.50 miles to the 60 dBu, which would fit within the 2 mV/m contour, AND it would
cover the main core of the city, including a small part of Gulf Breeze. This is the most logical setup.
What say you guys?
