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540 AM
- Thread starter PHIL Z
- Start date
PHIL Z said:
540 has been in use in North America since about 1933 (CKOK in Windsor, ON) and then in 1934 Canada changed the allocation to Moose Jaw and later Watrous, both around Regina.
Around early 1955, KFMB in San Diego moved from 550, while Cypress Gardens, Pocomoke City, Baton Roughe, Clarksvile, Monroe and Richlands went on the air.
Somewhere in the late 50's, a modification to NARBA gave 540 to Mexico to share with Canada for class 1 operations. XEWA in San Luis Potosí, SLP was licensed for 150 kw operation, non-directional while CBK retained 50 kw status. KFMB would be moved in about 1965 to 760 and I believe that the operation of KNOE was affected also.
David and/or Watt: Who was on 540 (or was it 550) in Baton Rouge?
DavidEduardo said:
I can't swear to this, but I believe that, by 1962, KFMB had already moved to 760 (5 kW DA-N; 50 kW-N came later). ISTR being in So Cal in the summer of '62 and listening to KFMB on 760. What is today's KBRT (it was KBIG then) was already on the air when KFMB moved to 760 and I remember being suprised that the FCC would permit the move because John Poole's advertising in Broadcasting before KBIG began regular broadcasts had boasted that KBIG would deliver 25 mV/m to both LA and San Diego. I have since seen data (the V-Soft Web site, I believe) that fails to confirm that KBRT delivers 25 mV/m to San Diego (it's close, though), but does confirm big-time normally prohibited second-adjacent overlap between KFMB and KBRT.
My previous posting is probably incorrect. I now believe that the trip to So Cal when I listened to KFMB on 760 did not take place in 1962 as I had said but rather in 1966. That would be consistent with the mid-sixties date of the move to 760 mentioned in David's message, to which I was replying.
DanStrassberg said:
I know I have a verification of reception of KFMB for reception in Quito in 1965. So they moved somewhere in the 65-66 time frame. I'm not positive, but I believe that the 50 kw night power was added considerably later, perhaps as SD population moved or spread to the north and east.
The State Department pretty much forced the FCC to violate protection requirements to put this operation on 760. But Mexico demanded an additional clear channel...
I lived in Riverside CA until May of 1965. KFMB made the switch some time before this. I am thinking maybe 1963 or 1964. They made a big deal about the change and had a contest asking listeners to try to guess when the change would occur (date and time-of-day). It happened in the morning at 9 or 10 AM but I can't remember the date. I actually listened to the switch when it happened.
For What its worth....I just spent 30 minutes researching on-line the KFMB frequency change from 540 to 760. I found two sources stating the change happened on May 21, 1962, although other dates as late and 1965 and 1966 are also to be found. But again, I KNOW they were well entrenched on 760 in early 1965 because I lived in Southern California at the time. Several sources reported the FCC mandated a frequency change for KFMB in 1961 to give Mexico the frequency. KFMB looked at several frequencies beside 760 including 550 (where they briefly hung out in the early 1950's), 830 and 1030 from what I read. There are also many references to continuing interference between KBRT-740 (formerly KBIG) and KFMB after the frequency change. This interference continues today with IBOC interference from KBRT alledgedly "infringing" on KFMB's signal in the San Diego area... There are references to the FCC getting involved in this IBOC matter...
DavidEduardo said:
KFMB's increase to 50 kW-N indeed took place well after its move to 760. In fact, I believe it did not happen until after the first Rio treaty, which I think dates to sometime in the mid-'80s. IIRC, that treaty, among other things, reclassified all AMs to alphabetic classes, did away with the old Roman-numeral classes, and removed the 1-kW limitation on the night power of secondary stations on the former Class IA channels. (On 760, KFMB became an exception to that rule, which didn't yet exist when KFMB was first granted 760.) After the treaty, KFMB was no longer a special case (except that it was a member of an unusual group of stations that run higher power at night than during the day and has another distinction mentioned below). I presume that KFMB's NIF is 100% established by first-adjacent interference from KKOB, which has a HUGE nighttime signal in So Cal. I suspect that, until the increase to 50 kW-N, KFMB's 5-kW NIF probably did not cover 80% of the population of San Diego.
KFMB's increase to 50 kW-N required the addition of a third tower and that tower is separated from the other two by a road, making KFMB one of a fairly small number of US AMs that have public roads running through their DAs.
I gather that KFMB's increase to 50 kW-N took place before the FCC changed the formulas for calculating the location of 10% skywave contours. With that change, KFMB must enter big-time into KGU's NIF. Since KGU is a real legacy station, the interference it receives from KFMB as calculated under the current formulas would almost surely not have been permitted and KFMB would likely have been restricted to 5-kW at night.
KR4BD said:
It must have been in early 1965 at the "soonest." I have a verification for reception in Quito, Ecuador... I did not go any DXing in my first year there, due to a lack of a receiver for the first few months, and then all the work putting a station on the air in December of '64 so the reception had to have been after the first months of '65. Didn't hear it on 760, ever, as that frequency was very congested in South America at the time; 540 was clear all the way to San Diego once the Bogotá station had signed off at midnight EST and XEWA at midnight CST... and my reception antenna was a tower tuned to 570, which I used after midnight... until I went 24/7 in mid '65... but that tower did not exist before late November, 1964. So my guess would be earluy '65. The 1965 Broadcasting Yearbook, based on early year data, still shows 1540.
KR4BD said:
White's Radio Log for June / July, 1965 and the one for August / September, 1965 have KFMB on 540.
The same source for October / November, 1965 has them on 760.
The SAMS Vane Jones 2nd Edition, 2nd Printing, July, 1964, also has KFMB still on 1964. This was probably the best source for information from the late 50's through the early 80's.
The FCC did not, technically, give 540 to Mexico, either. The State Department, in response to a Mexican demand for proportional iquality in the matter of clear channels, got the FCC to clean off 540 so it could be given to Mexico to share with Canada, which was a sort "pass the buck" solution that State was famous for in dealing with NABA. If left to the FCC, we'd have the same sort of thing as protecting Cuba, which abrogated NARBA, for decades or protecting stations in the DOmincan Republic that never were built, licensed or operating.
The May 21, 1962 date I mentioned might have been the date the FCC approved to move to 760. I found that date on two websites. In 1961, it was apparently determined that KFMB had to move off 540. I am sure all the frequencies under consideration and engineering studies would have taken some amount of time to implement. But AGAIN, I am sure they were on 760 in early 1965. I actually listened to KFMB make the changeover but don't remember exactly when it happened. I moved from California to Ohio in May of 1965.
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