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any thoughtssss

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fairbankshockeypuck
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any thoughtssss

Post by fairbankshockeypuck » Wed Feb 13, 2019 5:38 pm

I had asked a question and never got an answer....Maybe>>> we have am 970 5KW and 820AM 10kw..transmitters three miles north of town...same road...opposite sides and about a football field or so apart....Permafrost area.....wonder if those effect coverage areas....

24 AM FM'S in area of 30,000 city population...100,000 within 100 miles....'


several religious. LP..and translators....

FM fullpowers go out almost 100 miles



cckadlec
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Re: any thoughtssss

Post by cckadlec » Thu Feb 14, 2019 6:47 am

I'm confuzzled. Are you asking if the proximity of the towers affect each of their coverage areas? I'd elaborate on the permafrost comment, but the permafrost region doesn't start until just south of Hudson Bay, so I reckon you won't be seeing permafrost here until at least just before the next ice age. (However, I note your username mentioning Fairbanks, so perhaps that is important information for your post if you are located outside the general Michigan area...).

In addition, regardless of location, FM and AM cannot be compared. They propagate through completely unrelated means. FM propagates via the troposphere and AM via the ionosphere. They do not affect each other (unless through studio links or improper engineering; I could often hear my local North Korean AMs and TV on co-owned FMs originating from the same studio as they didn't have the best engineering practices).


[ Radio and weather geeks, beware! Coastal tropo studies, the 3-hr. Seoul AM Radio Listening Guide, 6-hr. 500 Top-of-Hour IDs, and Chinese FM at www.chriskadlec.comTuner: Grundig G8 • Location: Fremont, Mich. ]

k8jd
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Re: any thoughtssss

Post by k8jd » Thu Feb 14, 2019 1:28 pm

Local (daylight) AM signals actually are ture ground wave, where the transmitter antenna induces currents in the surface of the Earth !



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Vic Doucette
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Re: any thoughtssss

Post by Vic Doucette » Thu Feb 14, 2019 1:38 pm

cckadlec wrote:
Thu Feb 14, 2019 6:47 am
I'm confuzzled. Are you asking if the proximity of the towers affect each of their coverage areas? I'd elaborate on the permafrost comment, but the permafrost region doesn't start until just south of Hudson Bay, so I reckon you won't be seeing permafrost here until at least just before the next ice age. (However, I note your username mentioning Fairbanks, so perhaps that is important information for your post if you are located outside the general Michigan area...).

In addition, regardless of location, FM and AM cannot be compared. They propagate through completely unrelated means. FM propagates via the troposphere and AM via the ionosphere. They do not affect each other (unless through studio links or improper engineering; I could often hear my local North Korean AMs and TV on co-owned FMs originating from the same studio as they didn't have the best engineering practices).
The OP lives in Alaska.


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cckadlec
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Re: any thoughtssss

Post by cckadlec » Thu Feb 14, 2019 3:35 pm

k8jd wrote:
Thu Feb 14, 2019 1:28 pm
Local (daylight) AM signals actually are ture ground wave, where the transmitter antenna induces currents in the surface of the Earth !
Oops, totally didn't consider groundwave there. Thanks for the correction! (As if we barely have enough daylight this time of year for a handful of hours of decent groundwave...) :(


[ Radio and weather geeks, beware! Coastal tropo studies, the 3-hr. Seoul AM Radio Listening Guide, 6-hr. 500 Top-of-Hour IDs, and Chinese FM at www.chriskadlec.comTuner: Grundig G8 • Location: Fremont, Mich. ]

Deleted User 14888

Re: any thoughtssss

Post by Deleted User 14888 » Thu Feb 14, 2019 7:34 pm

First of all, Are these stations in Fairbanks, If they are where is KFAR 660 in all this, You mentioned 820 and I’m guessing it’s KCBF and 970 KFBX, So what is it that you’re asking that the fact the two stations 820 and 970 are cutting into each other’s signal could that be the question? In my opinion and I could be off on this, The permafrost could possibly effect the ground wave during the day, And as far as the night signal you may have normal skywave conditions.



k8jd
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Re: any thoughtssss

Post by k8jd » Sat Feb 16, 2019 5:26 pm

Stations with closeby other transmitting antennas are NOTHING,
There are many locations, where real estate is costly, where AM stations actually SHARE a tower or ARRAY. Co-located transmitters can use high Q filters to isolate each other and combine signals to feed ONE antenna system ! :eek



k8jd
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Re: any thoughtssss

Post by k8jd » Sat Feb 16, 2019 5:34 pm

One good example is Honolulu, there are 17 AM stations and only 7 towers placed around the city with shared transmitters/.!



fairbankshockeypuck
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Re: any thoughtssss

Post by fairbankshockeypuck » Mon Feb 18, 2019 4:52 am

KFAR is 10K and located southeast of Fairbanks towards North Pole. 660 and 820 have translators of 97.5 and 107.9 trying to lure a younger audience of news talk and sports.....107.9 gets out 20-25 miles on 4000 foot Ester Dome at 250W



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Ed Joseph
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Re: any thoughtssss

Post by Ed Joseph » Sat Mar 16, 2019 8:27 pm

Fairbanks, did you used to work in Central MI radio?


I confirm all my information through a high, white whore's souse!

k8jd
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Re: any thoughtssss

Post by k8jd » Sun Mar 17, 2019 2:10 pm

fairbankshockeypuck wrote:
Wed Feb 13, 2019 5:38 pm
I had asked a question and never got an answer....Maybe>>> igious. LP..and translators....

FM fullpowers go out almost 100 miles
Distance of FM coverage depends a LOT on the height of the antenna above average terrain. In AK a lot of mountain top FM can go amazing distances.
Here in S.E. MI we have slightly rolling terrain and some FM 50-100 KW can go down into the noise 30 miles from the antenna in certain directions.



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Ed Joseph
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Re: any thoughtssss

Post by Ed Joseph » Sun Mar 17, 2019 4:13 pm

k8jd wrote:
Sun Mar 17, 2019 2:10 pm
Distance of FM coverage depends a LOT on the height of the antenna above average terrain. In AK a lot of mountain top FM can go amazing distances.
Here in S.E. MI we have slightly rolling terrain and some FM 50-100 KW can go down into the noise 30 miles from the antenna in certain directions.
Indeed, height is the most important factor for VHF FM. I once mounted a Mr Microphone 60' up a tower, ran audio and 12VDC to it, and it easily covered a mile in each direction. That may have been likely less than 50 milliwatts.

AM stations are more dependent on a good ground system and ground conductivity. Clean positive modulation plays a part as well. The same station will get out quite a bit farther at +125% than at +99% modulation. When I was doing my short stint as 1230 WGRY's engineer, I could not get their AM to modulate for crap. First, the TX was hacked in many ways I never had the time to correct, and second, all they had was an Orban limiter with no asymmetry adjustment available. The result was the station, with it's practically all sand ground and short tower, barely got out beyond the Grayling city limits. WFLT, further up the dial on 1420, does quite well on their flea power setup, because their modulation is quite hot on the positive side.

In fact, I've done AM "experiments" years ago at home that had better coverage than WGRY!


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fairbankshockeypuck
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Re: any thoughtssss

Post by fairbankshockeypuck » Thu Mar 21, 2019 9:38 am

Ed Joseph wrote:
Sat Mar 16, 2019 8:27 pm
Fairbanks, did you used to work in Central MI radio?
Yes I did...WKNX/WSAM/WGER/WMPX before I migrated north to Alaska. Part time sports and play by play and full time grocery biz...Randy Bhirdo and Ric Allen gave me my start in 1979...



fairbankshockeypuck
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Re: any thoughtssss

Post by fairbankshockeypuck » Thu Mar 21, 2019 9:47 am

I also learned a lot from the late Lee Charles aka Lee Norling



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