A Question For Tech/Engineering Types

[Joseph_Gallant]

Recently, KBRT-740 moved it's transmitter from Catalina Island (26 miles off the coast, as the old song goes) to the mainland.

KBRT's pattern was directed towards the mainland, with less signal going out over the Pacific.

Unless the three KBRT towers have been dismantled (and I can't see that happening; I suspect at least one of them is also being used for cellphone service), I have a question which technical/engineering types on the West Coast may be able to answer: What if KFI-740 moved their transmitter from the mainland to Catalina Island, running 50,000 watts on 640 from the old KBRT towers, with a signal beamed towards the mainland??

Would the "26 miles" of salt water path between Catalina and the mainland expand their signal area so it's daytime signal would extending into Southwest Utah, western Arizona, and up the coastline to Monterrey (while their nighttime signal would reach further into the Central United States)???

KFI already is the biggest AM signal in Southern California; I was wondering if a move to Catalina and beaming the signal towards the mainland would expand their signal area on land while lessening the amount of signal "wasted" over the Pacific.

 

[ChannelFlipper]

Don't know anything about engineering, but it is not financially possible. They would not be able to monetize any of those additional listeners in those far out places, and they already have a lot of money tied up in the (almost) brand new tower at their current location. Therefore the substantial costs incurred in making such a move would not be recoverable.

 

[davideduardo]

What if KFI-740 moved their transmitter from the mainland to Catalina Island, running 50,000 watts on 640 from the old KBRT towers, with a signal beamed towards the mainland??

I believe that among the issues KBRT faced were increasingly unreliable electric power on the island, high costs of same, and a desire not to have towers and such "littering" the increasingly conservationist influenced horizon.

In any case, the 740 towers would be a little short and the pattern would have been devised for the wavelength relationships 100 kHz up the dial. The towers may already be down, as the local authorities did not want them as neighbors (cell phone antennae are not very common on AM directionals: I don't know of any personally.

Would the "26 miles" of salt water path between Catalina and the mainland expand their signal area so it's daytime signal would extending into Southwest Utah, western Arizona, and up the coastline to Monterrey (while their nighttime signal would reach further into the Central United States)???

Even if the station very severely directional, they would only be, perhaps, the equivalent of a 200 kw signal. That would double the useful coverage area, improving the signal to places like Santa Barbara, the Victor Valley, Palm Springs, etc. It would not be usable anywhere out of CA, and would likely not put a good day signal even to Blythe or Barstow or Calexico.

Since KFI can only monetize the signal in LA and Orange counties, the LA metro survey area. Added signal has zero payback and huge expenses.

 

[DrAkbar]

Crawford's lease is up the end of this year. After that the ground space goes back to what it was like before John Poole built the facility. Only question that remains unanswered is how much of what was a xmttr site does Crawford have to remove.

 

[fybush]

I had the privilege of being the last visitor to the KBRT site before Crawford signed it off, and I wrote about it here:

http://www.radioworld.com/article/one-of-americas-most-remote-am-sites-signs-off/217334

Joseph, there are no cell facilities at the KBRT Catalina site; it would be pretty pointless, because there'd be nobody served by any cell carriers there. KBRT's site was up in rugged mountainous terrain midway up the island, a long way up and out from the only population center, the city of Avalon. Nobody lives anywhere near the site, at least not now that the on-site engineer has moved away.

Crawford pretty much handed over the keys at the Catalina site to the conservancy when it shut down the transmitters; my understanding is that it will be up to the conservancy to decide when and how to dismantle the towers and remove the building.