Does anyone by any chance know which are all the AM stations with live antennas very close to residences or businesses? (I was drilling through Scott Fybush's site many moons ago trying to find them, but got overwhelmed and gave up on it.) I'm thinking something along the lines of having the buildings close enough to the towers to be on top of where the ground system would normally be.
This station, XEAZ-1270 in Tijuana, is a very good example of what I mean for physical distance separation between house and tower. Being only a 500-watt station, though, I doubt that it'd have as strong of a signal inside that house as KCBQ has in these two videos. (Based on a few other antenna comparisons that I have done, I'd guess I'm getting upwards of 50+ dB gain with that utility ground + Select-A-Tenna combination.) For comparison, the barefoot signal near this 2.5 kW DA's tower (photo only) was only about as strong as (or maybe at most a few dB stronger than, judging from the readings I think I remember on the 2nd harmonic which isn't included in the linked video) this SAT+utility-enhanced reception of KFMB 7.3 miles distant (specifically after the day/night pattern change in each mini-segment).
Would someone possibly know of any, for example, 50kW AMs that put a signal like what I'm implying into someone's house or a store, for example? Or at least what are the top several stations in terms of putting the strongest field intensity at a nearby store or house of someone who does NOT work for the station? Which ones put upwards of 154-166 dBµV/m at the nearest human-accessed building? (FCC maximum exposure (1.1310) for general population is about 175.763 dBµV/m below 1.34 MHz and 824/MHz V/m above that in the AM band.)
Bonus points for the nearest station ±10 kHz (if the local is not IBOC, otherwise ±20 kHz if it is) being far enough so its field there is about 14-30 dBµV/m. (Yes, you guess correctly that I'm also interested in knowing what radios (especially ones that could qualify as "ultralights") have good enough selectivity to pull in full NRSC audio on the DX with no splatter or blocking/desense from the local.
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Along the lines of an AM tower near a shopping center ... is there a way to combine good radiation efficiency (510 mV/m/kW or better), low land usage and ability to touch the tower while it's on the air? I understand a Franklin antenna has that efficiency and can do without a ground system (think KFBK and KSTP), combine that with a self-supporting tower and the only "land" the tower takes up is the size covered by the tower base, approximately, and a shunt-fed antenna (saw a pic and article on Scott Fybush's site but I can't find it anymore, also I thought I remembered someone leaning up on KFBK's tower in that article) would allow one to touch the tower (at its base) while it's on the air.
I may be the only one who thinks this, but for example, I think it'd be quite interesting to go to the food court in the local mall, order my lunch, sit down at a table, and look up and see this, especially if it's a 600-kHz-or-below self-supporting true Franklin. (I'd bet the chances of it being one of the towers of a directional Disney/Nickelodeon/etc format signal with a pattern plot like this (WARNING: may be considered NSFW - btw I think I've seen a plot somewhat similar to that on a station somewhere, can't remember which one, though) would be rather slim, though. hey what type of config (tower ratios, electrical height, phasing, spacing, orientation, etc) might it take to get a pattern similar to that, using as few towers as possible?)
Also what would be some overseas (from the U.S.) mediumwave and longwave stations with transmitter sites very close to the ocean? I'm thinking similar to 660-WFAN/680-WCBS and 1250 KZER, but with preferably higher power (up to 2 MW or whatever their maximum is) transmitters (and an all-saltwater path to USA coastal locations, especially southern California, would be nice), and am especially interested in stations from 153 kHz to, say, 810 kHz or so (but the entire band is fine).
Also, along a saltwater path, if a piece of land intrudes into the path, would the groundwave continue following the shortest distance (great circle) path and cut through the land (being attenuated accordingly)? Or, would it bend around the land, staying on the saltwater, making the path maybe a few percent longer but following the path of least resistance (and being a higher field strength than if it had cut straight across the piece of land and been attenuated accordingly)?
This station, XEAZ-1270 in Tijuana, is a very good example of what I mean for physical distance separation between house and tower. Being only a 500-watt station, though, I doubt that it'd have as strong of a signal inside that house as KCBQ has in these two videos. (Based on a few other antenna comparisons that I have done, I'd guess I'm getting upwards of 50+ dB gain with that utility ground + Select-A-Tenna combination.) For comparison, the barefoot signal near this 2.5 kW DA's tower (photo only) was only about as strong as (or maybe at most a few dB stronger than, judging from the readings I think I remember on the 2nd harmonic which isn't included in the linked video) this SAT+utility-enhanced reception of KFMB 7.3 miles distant (specifically after the day/night pattern change in each mini-segment).
Would someone possibly know of any, for example, 50kW AMs that put a signal like what I'm implying into someone's house or a store, for example? Or at least what are the top several stations in terms of putting the strongest field intensity at a nearby store or house of someone who does NOT work for the station? Which ones put upwards of 154-166 dBµV/m at the nearest human-accessed building? (FCC maximum exposure (1.1310) for general population is about 175.763 dBµV/m below 1.34 MHz and 824/MHz V/m above that in the AM band.)
Bonus points for the nearest station ±10 kHz (if the local is not IBOC, otherwise ±20 kHz if it is) being far enough so its field there is about 14-30 dBµV/m. (Yes, you guess correctly that I'm also interested in knowing what radios (especially ones that could qualify as "ultralights") have good enough selectivity to pull in full NRSC audio on the DX with no splatter or blocking/desense from the local.
)Along the lines of an AM tower near a shopping center ... is there a way to combine good radiation efficiency (510 mV/m/kW or better), low land usage and ability to touch the tower while it's on the air? I understand a Franklin antenna has that efficiency and can do without a ground system (think KFBK and KSTP), combine that with a self-supporting tower and the only "land" the tower takes up is the size covered by the tower base, approximately, and a shunt-fed antenna (saw a pic and article on Scott Fybush's site but I can't find it anymore, also I thought I remembered someone leaning up on KFBK's tower in that article) would allow one to touch the tower (at its base) while it's on the air.
I may be the only one who thinks this, but for example, I think it'd be quite interesting to go to the food court in the local mall, order my lunch, sit down at a table, and look up and see this, especially if it's a 600-kHz-or-below self-supporting true Franklin.
(I'd bet the chances of it being one of the towers of a directional Disney/Nickelodeon/etc format signal with a pattern plot like this (WARNING: may be considered NSFW - btw I think I've seen a plot somewhat similar to that on a station somewhere, can't remember which one, though) would be rather slim, though. hey what type of config (tower ratios, electrical height, phasing, spacing, orientation, etc) might it take to get a pattern similar to that, using as few towers as possible?)Also what would be some overseas (from the U.S.) mediumwave and longwave stations with transmitter sites very close to the ocean? I'm thinking similar to 660-WFAN/680-WCBS and 1250 KZER, but with preferably higher power (up to 2 MW or whatever their maximum is) transmitters (and an all-saltwater path to USA coastal locations, especially southern California, would be nice), and am especially interested in stations from 153 kHz to, say, 810 kHz or so (but the entire band is fine).
Also, along a saltwater path, if a piece of land intrudes into the path, would the groundwave continue following the shortest distance (great circle) path and cut through the land (being attenuated accordingly)? Or, would it bend around the land, staying on the saltwater, making the path maybe a few percent longer but following the path of least resistance (and being a higher field strength than if it had cut straight across the piece of land and been attenuated accordingly)?
