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History and Order of Mount Wilson?

My impression has always been that the channel numbers started at 201 because they did not want to conflict with television and for that matter, AM radio as many stations were promoting with the last "0" taken off of their frequency (i.e. "64 KFI", "93 KHZ", "KRIZ Radio 123", etc.") Some of the first FM radios for 88~108 were marked by channel number, but the channel number thing never took off. In addition to the United States, Mexico, Canada, the Philippines and some Caribbean and Latin American nations also adopted the channel numbers in their regulations as they adopted the 200 kHz spacing method. While even to this day, I still have to use a channel number to frequency conversion chart, the channel numbers make it much easier to design the systems we all use at REC for broadcast related stuff.
 
Just a reminder, fccdata.org does have the historic records of the Los Angeles area AMs and FMs going back to their starts. Just look up the station as it stands today and you will find the historical data there.
 
DavidEduardo said:
RF danger for people working on Mt Wilson near their site.
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If KBIG had to reduce ERP because of the RF danger, they why has KPFK been allowed to keep its 110kw? Is the KPFK antenna a bit further from areas where people might be working? Or are the rules different for non-comms? Because KQED 88.5/San Francisco runs 110kw from a similar antenna farm that has public access.
 
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Michi said:
My impression has always been that the channel numbers started at 201 because they did not want to conflict with television and for that matter, AM radio as many stations were promoting with the last "0" taken off of their frequency (i.e. "64 KFI", "93 KHZ", "KRIZ Radio 123", etc.") Some of the first FM radios for 88~108 were marked by channel number, but the channel number thing never took off. In addition to the United States, Mexico, Canada, the Philippines and some Caribbean and Latin American nations also adopted the channel numbers in their regulations as they adopted the 200 kHz spacing method. While even to this day, I still have to use a channel number to frequency conversion chart, the channel numbers make it much easier to design the systems we all use at REC for broadcast related stuff.
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And you correctly say "some... Latin American nations" adopted the channel numbers. I had, at one time, about 20 FM licenses in Ecuador and none had channel numbers on them. I got the first one around 1965, and then got more in groups over the next few years.
 
Signal Geek said:
If KBIG had to reduce ERP because of the RF danger, they why has KPFK been allowed to keep its 110kw? Is the KPFK antenna a bit further from areas where people might be working? Or are the rules different for non-comms? Because KQED 88.5/San Francisco runs 110kw from a similar antenna farm that has public access.
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The rules are not different for noncoms. Many of the stations on Wilson are grandfathered pre-1962 operations. If a Class B station wanted to move to Wilson right now, they would be limited to about 890 watts ERP. For stations that are grandfathered super power, they do have some limitations. For example, when calculating the power allowed for HD, they have to base it on full Class B facilities and not their super power. Also, in the 1962 Order, the FCC had noted at the time that while stations can run super power, they will not necessarily be protected at their super power. I have been successful in the past in getting inside of second and third adjacents of super powered stations as long as their full Class parameters were protected. In the LPFM rules, commercial band super power stations are considered at their station class, however reserved band super power stations are considered at a higher service class. For example, KPFK would need to be protected by LPFMs as if it was a Class C even though Class C stations are not available in that part of California. (See §73.807, note to paragraphs (a) and (b)).
 
I did some more digging and while this does not answer the original question, it does add some detail:

The original proposed 1945 table of FM allocations operated on the strange presumption that only one channel spacing needed to be used between stations and clustered allocations in cities and metropolitan areas:

By 1947, the Commission was realizing that wouldn't work:

... and reallocated existing stations to four-channel separation in the same city or metro area:

The idea of starting at channel 200 was to allow for possible expansion of the band without having to renumber existing allocations:

Most radio receiver manufacturers said they planned to use channel numbers rather than frequencies going forward:

In 1948, the promotion manager of WIL-FM St. Louis suggested that even the "2" be dropped and everything be identified on radio sets and on the air as "channels 0 through 100":

And from what station print advertising I could find, the shortening of AM frequencies to things like "89" or "134" on the air wasn't happening this soon in radio history. That appears to have begun in the mid- to late-1950s. Before then, it was always the full three- or four-digit frequency.
 
K.M. Richards said:
Most radio receiver manufacturers said they planned to use channel numbers rather than frequencies going forward:
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Hmmm. Interesting idea. Does anyone have one of those radios with the channels instead of frequencies? I can't recall ever seeing one.

I always wondered why they used such a complicated way of identifying FM stations. Seems like there would be an easier way.

EDIT: After mulling this over, it struck me that in the 1940s FM was still a patented licensed technology. So it's possible that's why the manufacturers stayed with frequency instead of channel. They had to under the terms of the license.

K.M. Richards said:
And from what station print advertising I could find, the shortening of AM frequencies to things like "89" or "134" on the air wasn't happening this soon in radio history. That appears to have begun in the mid- to late-1950s. Before then, it was always the full three- or four-digit frequency.
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I have an old Philco portable made of wood (pre-transistor) and it has the AM frequencies shorted as 55 to 150. Wonder if the radio is worth anything.
 
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K.M. Richards said:
Channel 1 was 50-56 in 1941, then 44-50 in 1945 after FM was moved. It was formally removed in 1948.

History of UHF Television

uhfhistory.com uhfhistory.com
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I did that in my head and should've said 48-54 for channel 1. It looks like the protective band(between 4 & 5)was not yet employed, which would explain the difference. I just assumed that channel 1 was just before 2. I had no idea it had moved, which tells me that they must have moved the entire low VHF band!
 
TheBigA said:
I always wondered why they used such a complicated way of identifying FM stations. Seems like there would be an easier way.
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I'm thinking that it might have had something to do with how long it took FM to catch on. We know from one of those articles I linked to that everything was on the 88-108 band by the end of 1947, but it wasn't until 20 years later that AMs stopped simulcasting on their co-owned FMs and some standalone FMs started getting notice. It wasn't until the 1970s that FM really began to catch on.

By that time, "channels" was ingrained in the public's mind as being "television" and everyone knew "radio" was identified as "a number based on the dial position". It also didn't help that a lot of those simulcast AM/FMs never even mentioned the FM's dial position ... even in local small-town situations; where I grew up -- Ventura -- KVEN-FM 100.7 simulcast KVEN 1450 all day beginning in 1962 and continued to do so for 11 years. Other than "KVEN and KVEN-FM, Ventura" once an hour few people even knew the FM existed, much less its frequency, until 1973 when they split it off as KHAY.
 
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K.M. Richards said:
I'm thinking that it might have had something to do with how long it took FM to catch on. We know from one of those articles I linked to that everything was on the 88-108 band by the end of 1947,
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The article quoted a manufacturer saying they wanted to use channels. However I haven't seen any examples that show they ever did.
 
Here is the history of order as recorded by the REC Radio History Project.
Listing is in order of CP grant date. Call signs in effect on CP grant date as well as the modern calls are shown:

93.1 KCBS (was K31LA) (orig CP 43.1 07/16/41, cancelled 11/27/42) (new CP on 43.1 11/30/42, LIC 93.1 12/7/50)
94.7 KTWV (was KVUN) (CP 10/31/46, LIC 06/30/49)
95.5 KLOS (was KECA) (CP on 99.3 10/31/46, LIC on 99.5 09/27/55)
92.3 KRRL (was KFAC) (CP orig 95.7 01/27/47, LIC on 104.3 09/26/51) to 92.3: (CP 04/14/54, LIC 01/14/55)
101.1 KRTH (was KHJ-FM) (CP 02/03/52, LIC 07/14/52)
104.3 KBIG (was KPLA) (CP 12/18/57, LIC 03/06/59)
105.1 KKGO (was KBCA) (CP 09/12/58, LIC 05/04/59)
90.7 KPFK (CP 11/25/58, LIC 01/22/64)
102.7 KIIS (was KLAC-FM) (CP 09/02/59, LIC 03/06/61)
103.5 KOST (was KGLA) (CP 07/01/60, LIC 06/16/61)
107.5 KLVE (was KBBI) (CP 12/04/62, LIC 08/14/64)
101.9 KSCA (was KUTE) (CP 04/23/69, LIC 12/01/70)
100.3 KKLQ (was KIQQ) (CP 04/01/82, LIC 09/05/85)
89.3 KPCC (CP @ 600w 11/17/87, LIC @ 600w 02/21/89)
97.1 KNX-FM (was KLSX) (CP 06/02/88, LIC 01/10/90)
93.9 KLLI (was KZLA) (CP 07/03/91, LIC 12/06/91)
105.9 KPWR (CP 03/13/92, LIC 07/15/93)
99.5 KKLA (CP 11/20/92, LIC 02/17/95)

91.5 KUSC (Mt Harvard, CP @ 17kW 03/31/94, LIC @ 39kW 04/26/00) Not sure how they got away with this. This was a BAPS CP application so there are no exhibits available online.
 
Michi said:
The rules are not different for noncoms. Many of the stations on Wilson are grandfathered pre-1962 operations. If a Class B station wanted to move to Wilson right now, they would be limited to about 890 watts ERP. For stations that are grandfathered super power, they do have some limitations. For example, when calculating the power allowed for HD, they have to base it on full Class B facilities and not their super power. Also, in the 1962 Order, the FCC had noted at the time that while stations can run super power, they will not necessarily be protected at their super power. I have been successful in the past in getting inside of second and third adjacents of super powered stations as long as their full Class parameters were protected. In the LPFM rules, commercial band super power stations are considered at their station class, however reserved band super power stations are considered at a higher service class. For example, KPFK would need to be protected by LPFMs as if it was a Class C even though Class C stations are not available in that part of California. (See §73.807, note to paragraphs (a) and (b)).
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That's all very interesting, but doesn't answer my question. Why did KBIG have to reduce power, but KPFK didn't?
 
Michi said:
Here is the history of order as recorded by the REC Radio History
91.5 KUSC (Mt Harvard, CP @ 17kW 03/31/94, LIC @ 39kW 04/26/00) Not sure how they got away with this. This was a BAPS CP application so there are no exhibits available online.
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How DID KUSC get away with this? I asked this same question on this board years ago, and did not get an answer. KUSC was a standard Class B signal in the early 80s, from a pole near the summit of Beverly Hills (not the current KYSR/KCRW tower), then remained at B parameters when they moved east to Flint Peak -- but somehow got a jump in both power *and* HUGE jump in elevation when they moved to Mt. Harvard. Maybe a big donation from rich alumni to the FCC? 🙄
 
Signal Geek said:
but somehow got a jump in both power *and* HUGE jump in elevation when they moved to Mt. Harvard. Maybe a big donation from rich alumni to the FCC? 🙄
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I did a little search and found this:

KUSC’s New Transmitter and Antenna Boost Power to Classical Music Fans

KUSC-FM IS STARTING the millennium with a gift for Southland classical music fans – a brand-new transmitter and antenna, a healthy jolt of additional power and some new digital equipment. “Our signal will be clearer, stronger and more reliable,” said […]
news.usc.edu news.usc.edu

Since 1992, KUSC has been plagued with interference and other technical problems caused by a station broadcasting from Mexico. In an attempt to rectify the situation, authorities moved the Mexican station’s signal to 91.7 megahertz in 1993. KUSC increased its power a few months later and moved its transmitter from Flint Peak (1,900 feet) to Mount Harvard (5,440 feet).

“Unfortunately, those actions did not halt the interference,” Pennell said. “We’ve continued to receive complaints from listeners in Orange and Los Angeles counties and sometimes from as far north as Ventura County.”
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Apparently they had interference problems from a station in Mexico. They couldn't fix that problem, so it looks like they wanted to overpower the interferer. It's like you have a pest problem and you solve it with a sledge hammer.
 
TheBigA said:
I did a little search and found this:

KUSC’s New Transmitter and Antenna Boost Power to Classical Music Fans

KUSC-FM IS STARTING the millennium with a gift for Southland classical music fans – a brand-new transmitter and antenna, a healthy jolt of additional power and some new digital equipment. “Our signal will be clearer, stronger and more reliable,” said […]
news.usc.edu news.usc.edu



Apparently they had interference problems from a station in Mexico. They couldn't fix that problem, so it looks like they wanted to overpower the interferer. It's like you have a pest problem and you solve it with a sledge hammer.
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Thanks Big A for the research. But I don't buy the premise that KUSC somehow got to break the rules because of interference from Tijuana's XHGLX. When the T.J. station moved up one channel, bingo, that would have ended the interference. So why did KUSC get that big signal increase *after* XHGLX moved?
 
Signal Geek said:
Thanks Big A for the research. But I don't buy the premise that KUSC somehow got to break the rules because of interference from Tijuana's XHGLX. When the T.J. station moved up one channel, bingo, that would have ended the interference. So why did KUSC get that big signal increase *after* XHGLX moved?
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There are AM stations that have done that to override Cuban interference!
 
Signal Geek said:
I don't buy the premise that KUSC somehow got to break the rules because of interference from Tijuana's XHGLX. =
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I don't see anything that says they're breaking the rules.

I do see the license application dated 4/26/00 in the FCC database with this ID# 20000404ABH

So perhaps you can get more info there.
 
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