If you do try to DX KCBS - Post a Vid, I want to hear it
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AM Frequency of the week--740
- Thread starter ddsparxx
- Start date
Last night was interesting on 740.
WYGM was nowhere to be heard after a while anf KTRH was dominating with a good signal. There were other stations in the background including some Spanish station.
Then a news talk station in the background of KTRH got stronger and stronger until it took over KTRH.
It was KRMG. That's the first time I've ever heard that station. I thought it couldn't be heard here because of their pattern.
Unfortunately, there was nothing I heard that I thought was KCBS. I listened for their sounder but didn't hear it.
With all the power KCBS sends to the SE, it should have the potential to be heard when the circumstances are just right, IMO.
WYGM was nowhere to be heard after a while anf KTRH was dominating with a good signal. There were other stations in the background including some Spanish station.
Then a news talk station in the background of KTRH got stronger and stronger until it took over KTRH.
It was KRMG. That's the first time I've ever heard that station. I thought it couldn't be heard here because of their pattern.
Unfortunately, there was nothing I heard that I thought was KCBS. I listened for their sounder but didn't hear it.
With all the power KCBS sends to the SE, it should have the potential to be heard when the circumstances are just right, IMO.
C
cd637299
Guest
gar, that was quite a coup, getting KRMG.
I think that the only way to bag KCBS in FL is if no other 740s were on at night....at all.
cd
I think that the only way to bag KCBS in FL is if no other 740s were on at night....at all.
cd
Keep on trying....
cd637299 said:
Absolutely correct.
There are too many other 740s between FL and San Francisco and there's less than 50 kw pointed at FL by KCBS in the first place. If you had no KRMG and no CFZM and no KTRH and nothing from Latin America and no others, plus low RF interference from household appliances/wi fi/etc. and no adjacent channel interference - then it's theoretically possible.
Daytime: Zip
Nighttime: CFZM Toronto, pretty loud and clear
Nighttime: CFZM Toronto, pretty loud and clear
KCBS is a tough catch in the Eastern US to be sure. Since “gar fla” in particular is trying so hard for this station, I thought a comparison of nighttime signals of some of the 740 stations toward the Tampa area would be of interest. I have used the site of the WFLA transmitter to represent “Tampa”.
For the sake of these numbers, I have used the amount of signal of WSB-750 as a “standard” 50 kw signal.
KRTH transmits an effective 4750 watts toward Tampa at night, at 830 miles. (14kw day).
KRMG transmits an effective 14 kw toward Tampa at night, at 1022 miles.
KCBS transmits an effective 12.5 kw toward Tampa at night at 2394 miles.
KCBS gets stronger going South from Tampa, KRMG gets stronger going North. By the way, the area of the East coast right in the middle of KRMG’s nighttime lobe is between Charleston and Myrtle Beach, SC.
Note that KRMG and KCBS put comparable signals toward Tampa, but with KCBS being well over twice as far away, KCBS will usually be a lot weaker than KRMG.
AM DXing from Southern Connecticut and various areas in upstate New York in the 60’s and 70’s, I logged several California stations, but KCBS was not one of them.
For the sake of these numbers, I have used the amount of signal of WSB-750 as a “standard” 50 kw signal.
KRTH transmits an effective 4750 watts toward Tampa at night, at 830 miles. (14kw day).
KRMG transmits an effective 14 kw toward Tampa at night, at 1022 miles.
KCBS transmits an effective 12.5 kw toward Tampa at night at 2394 miles.
KCBS gets stronger going South from Tampa, KRMG gets stronger going North. By the way, the area of the East coast right in the middle of KRMG’s nighttime lobe is between Charleston and Myrtle Beach, SC.
Note that KRMG and KCBS put comparable signals toward Tampa, but with KCBS being well over twice as far away, KCBS will usually be a lot weaker than KRMG.
AM DXing from Southern Connecticut and various areas in upstate New York in the 60’s and 70’s, I logged several California stations, but KCBS was not one of them.
What about sunset/sunrise enhancement?For example, KBRT Avalon, CA, is 10kW daytime, directional with a null approximately to the west, and consequently a fair amount of signal aimed generally east. I wonder how far east into the USA that station might go in the late afternoon before sunset (7pm PDT this month) at the transmitter site on Catalina island?
Also, since the topic is 740 kHz, are there "daytimers" (including those with a huge day/night power/pattern difference - for example KBRT is licensed for 113 watts at night, but afaik only uses it from 6am to sunrise when applicable) on 740 toward the east of the USA that put a good signal to the west, and may reach a considerable distance after sunrise at the transmitter?
tfcwings said:
Not really, but one that might come close to fitting in that category is KVOX Fargo ND. It runs 50kW day with about half of the signal going west, although their power during critical hours is reduced to 7.5kW.
Incidentally, maybe you've noticed that KBRT has a pending application to increase their power to 50kW. They need to get off Catalina Island (lease and/or NIMBY problems) and are proposing to build a new array on the former site of 830 KLAA. Nighttime power would go up also, but only to 190 watts.
jd said:
KCBS can't be happy about that.
jd said:
Yes, I had noticed that. I Google mapped their proposed transmitter site and looked at the pattern in the FCC database, and it kind-of looks like there is room for improvement for serving the Southern California area.
Also, I've had a couple ideas for another way to maybe do things....
Move 730 XEEBC Ensenada, BCN, to 780 kHz, transmitter site about halfway between Rosarito & Ensenada, using a directional pattern similar to that of KMIK or KFXR's night patterns (or compare it to another narrowly-focused station with a huge lobe in one direction and virtually nothing everywhere else), but aimed south toward Ensenada. (Not sure what transmitter power should be, but the signal shouldn't reach the US border at San Diego, CA, on ordinary consumer equipment, day or night. BTW FCC database has them listed on 2 frequencies, but here in El Cajon, CA, I've heard a weak spanish station on 730 when using a tuned loop antenna aimed to null KBRT, although their IBOC does make it more difficult now.)
Move 740 KBRT to 730 kHz, and put their transmitter site some distance east of I-15 (preferably east of state route 79) - far enough so that even if they send virtually NO signal to the east, they can still have a solid signal as far east as places like Yucaipa, Hemet, Ramona, Alpine, etc. One place I thought of was on the shore of the Salton Sea (due to the ground conductivity of the salt water there, and it would also enable them to hit Palm Springs & El Centro), but even with a directional pattern with a huge lobe aimed right toward L.A. & Long Beach (and the sides of the lobe hitting San Diego and San Bernardino), I wonder if that would be a bit far out for a site. Is there another site east of Hwy 79 or I-15 that has good ground conductivity? Also another reason I was thinking of putting them so far out is so they can also have 50kW at night, serve most of southern California (well, maybe not eastern so Cal near the Colorado River), AND protect 730 XEX in Mexico City. (Also I'd change the COL, maybe Long Beach, Perris, or something, but IDK what.)
Another idea I previously had for "730" KBRT was dual-site operation - a daytime 50kW (directional mostly aimed east) transmitter on some island out in the Pacific (either the farthest west island at Channel Islands National Park or the island west of San Clemente & Santa Catalina hosting the San Nicolas Naval Facility; night site would use Salton Sea or something), but apparently they want to get off the islands.
Also, this seems like it would enable 760 KFMB in San Diego, CA, to increase its day power to 50 kW.
And, if KBRT would send the [>censored<] IBOC to the place mentioned in Revelation 20:10 (KBRT is, after all, running a religious format), it might enable DXers in San Diego & L.A. with good equipment to hear KCBS in the day. I can already sometimes hear KNBR & KOGO at noon in El Cajon, CA, but KCBS, which I'd think should be stronger due to its directional pattern, is blocked by KBRT.
Is that idea totally far fetched? (I'm mostly wondering about the technical aspects - station patterns, interference with others, adequate coverage, etc, and at this time not really considering the costs of such a move.)
Day or night??
If it's in the day time, it prolly kill KCBS going to the North
If it's at night..it will kill KCBS in the South
dx1ng said:
With only 4.75 kw, KTRH has a pretty good signal here at night. It actually sounds like any 50 kw non directional station would at 830 miles.
It's also interesting to note how 14 kw for the daytime in this direction gives as good of a signal as it does at the beach in the daytime.
Now considering the strength of the signal of KTRH directed here at night at 4.75 kw and the 12.5 kw from KCBS at three times the distance, shouldn't that mean KCBS should be audible when the conditions are right?
Correct. I hear KRMG at night about twice a month mixing with Toronto in Charleston. When it does come in, it is strong.
tfcwings said:
This kind of idea has been written about elsewhere before: I don't believe two stations with only 20 kHz of separation would be feasible in a U.S. metropolitan area with these kinds of power levels and field strengths! 30kHz is the closest that two stations could be placed in the same general area! (and the new/relocated KBRT would have to protect the 1st, 2nd and 3rd adjacent frequencies of the dominant station, in this case KSPN, with certain signal contours that cannot be overlapped except by using a highly directional array of towers to protect the dominant station) (and, to a similar extent, KFMB) KBRT is fine right where they are at 740. Sorry it will mess up some people's reception (DXers) of KCBS north of L.A. in the daytime, but it's well outside of the S.F. Market. Perhaps someone like Richard Fry or David Eduardo could fill us in on the technical details pertaining to the signal contours for the 1st-2nd-3rd adjacent AM frequencies in a metropolitan area!
Plus 730 is an "International" frequency, Canada and Mexico have priority according to NARBA. Though there are a few U.S. stations that operate at night (with very low power), none are above 15kW daytime and those that have higher power are usually very far away from the borders, and none are more than 1kW at night. It would take years for Mexico and Canada to approve and co-ordinate a full-time U.S. station on 730, IF they approved that. And good luck having the Mexicans and Canadians moving around some station's frequencies to accommodate us! And even though a number of Canadian and Mexican stations are leaving AM for FM, the FCC has to "protect" non-existent "stations". That would be nice if they gave up their radio territory so that we could squeeze more stations into our already crowded RF jungle...NOT gonna happen!
stormy01 said:
There are some weird crowded frequency situations already existing in Southern Cal. You have in the LA area 670, 690, & 710. In addition 1070, 1090, & 1110. Now I know that 690 & 1090 are on the Mexican border, but they run strong signals & are highly directional at LA.
When I used to drive around LA years ago the two Mexico stations were like locals and I'd sometimes get hets & lots of interference on those frequencies.
What about 1030 XESDD in Rosarito and 1040 KURS in San Diego? XESDD sends a LOT more signal north into San Diego than the database says. Here in El Cajon 11 miles from 1040's site, the two stations both come in at about the same strength (comparable to how KNX is received in the day at my location, and I believe I've posted recordings of that previously), and most of my radios (even one with a fairly wide IF filter) have virtually no problem separating the two through most of the area, including at home.
About the only place my Tecsun PL-606 really has any difficulty is very close to 1040's transmitter site. (On the other hand, it fails miserably at separating a very faint signal (something like maybe 100 uV/m) from a first-adjacent very strong one (more like upwards of 1,000 mV/m.))
If the two stations can co-exist closely spaced in more ways than one, why couldn't the others?
About the only place my Tecsun PL-606 really has any difficulty is very close to 1040's transmitter site. (On the other hand, it fails miserably at separating a very faint signal (something like maybe 100 uV/m) from a first-adjacent very strong one (more like upwards of 1,000 mV/m.))
If the two stations can co-exist closely spaced in more ways than one, why couldn't the others?
jd said:
They became unwelcome guests on the island after a subcontractor started a fire two years ago... burnt hundreds and hundreds of acres. Further, the infrastructure is deteriorating there, and electric power is not stable. The cost of running a genny would be too high, also.
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