The Southern Ontario/WNY Radio-TV Forum » Radio’s Morning & Evening “Pattern Change” Has Certainly Changed

RadioActive · October 23, 2019 9:47 pm

The only time I ever really thought about pattern change – when a radio station powers up or down its signal at sunrise or sundown or alters where its signal is aimed – was on my very first job at a radio station when I was just 15.

Being a radio crazed kid, I was aware of the reason for it, but I’d never seen it actually done. In those days, I remember the operator in the early morning had a set schedule, and at the place I was in at the time, she (it was a lady board op) dialed a specific single number (I think it was “9”) on what looked like an old rotary dial phone, which wasn’t a real phone at all, powering up the station in the morning to 50,000 watts from the meager 500 or so they’d been on all night. This would have been sometime around 1974

This all came back to me at 7:42 in the morning this week, when I heard CFRB’s pattern change, leaving 1½ seconds of dead air, before it came back as loud as ever. They, of course, have to guard against interfering with WINS in New York at night, also a 50K outlet at 1010.

Today, I would imagine it’s all automated down to the second, but back in those days, someone had to deliberately make the change happen. And with so much else going on in a radio station’s control room during a morning show, I often wonder what might have happened if someone forgot to make the move.

I admit I didn’t know a lot about the technical aspects of pattern changes or how it was accomplished elsewhere back then, but I just remember that odd rotary dial phone that that wasn’t a phone at all. And to this day, every time I hear that brief interruption to a signal, it puts me right back there.

betaylored · October 24, 2019 3:26 am

Seriously cool and interesting post RA, I think we've all heard a radio station do this, and depending on how much of a radio background we have thought "well that was weird" or "hmmm, pattern change." If I've got the radio on, dead air can still grab my attention, even one and a half seconds worth, it's like a blip on the radar, an "oh oh, what's going on" alert.

andysradio · October 24, 2019 7:09 am

1010 is (or was) a Canadian clear channel. I think I read somewhere that WINS needed special permission to use that frequency. So it is the other way around: WINS needs to protect NT1010 although they are not doing a very good job of it. CFRB is virtually unlistenable at night in Peterborough mainly because of them.
Incidentally, does anyone know what the NT pattern change achieves? Where is the pattern changed to/from

RadioActive · October 24, 2019 7:19 am

I believe you're right about 1010 being a Canadian clear channel, but what I meant was they have to protect against each other. But even in Toronto, I can frequently hear WINS in the background on CFRB in the dark. It's not loud or overpowering here, but it's certainly noticeable at times.

As for that old setup I referred to, it's been a very long time but I think the number they dialed to power down was zero, with 9 being the digit that sent it back to 50K. And of course once they went down to 500 watts at sundown, you were lucky to get them outside of the direct neighbourhood.

We have certainly come a long way since then.

zed · October 24, 2019 8:08 am

In the 60's, Leamington's CJSP was a day timer only. When it went top 40 and changed calls to CHYR they got an adjacent frequency for night time. At sunset they would play "it's fine tuning time - please adjust your radio to this sound" and a squiggly little sounder would play as the 10,000 watt 710 signal went off and the 500 watt 730 signal would come on. I never hear the night time signal because I was too far away. Always thought that was weird but for their central market at least it gave them a 24 hour station.

mace · October 24, 2019 8:24 am

According to the New Jersey based National Radio Club, Canadian clear channel stations have priority on 690, 740, 860, 990, 1010 and 1580. Mexico has priority on 730, 800, 900, 1050, 1220 and 1570. The U.S. has priority on the rest of them.

fybush · October 24, 2019 3:23 pm

Across the lake here at WXXI 1370, we did our pattern changes manually until just a few years ago. I didn't get to have that fun myself in the studio - the "operator on duty" was the master control person downstairs in WXXI-TV master control, where the remote control panel for the AM transmitter resides.

Now it's done automatically on a timer, and what's more, they changed the studio-transmitter link so that there's just a smidge too much delay for me to use the AM air signal as my headphone monitor in the studio. So I've lost the fun of listening to myself in the cans as I'm doing the top-hour ID and hearing the carrier drop and come back up again.

TheConsultant · October 24, 2019 3:58 pm

mace wrote:
Canadian clear channel stations have priority on 1580.

What kind of a blowtorch could the 1580 frequency actually punch out?

potentiometer · October 24, 2019 4:23 pm

@ zed. It could be apocryphal, but I heard CHYR actually changed call letters when it moved up the dial and became CHIR. I always thought that was very clever since they could still call themselves, "CHEER."

Dale Patterson · October 24, 2019 9:40 pm

Anyone here FORGET to do a pattern change when they were supposed to? What were the consequences.

RadioActive · October 24, 2019 10:09 pm

potentiometer wrote:
@ zed. It could be apocryphal, but I heard CHYR actually changed call letters when it moved up the dial and became CHIR. I always thought that was very clever since they could still call themselves, "CHEER."

It's not a myth. That actually happened. The Leamington station had two sets of call letters, CHYR at 710 and CHIR at 730. They also had two licences with the different calls. The outlet moved to FM in 1993.

I honestly can't recall another AM radio station anywhere in North America with this kind of odd frequency switching arrangement, but it did allow them to be on the air 24 hours a day. Although I'll bet they never got the chance to use that old radio cliche slogan, "Don't Touch That Dial!"

As usual, YouTube provides the proof.

berlin rych · October 24, 2019 11:17 pm

One of first things taught when I first began running a board (taught by Darryl Dahmer no less, in his Kitchener CKKW life) was taking the hourly readings. Our AM-er at 1320 and later 1090 had a strange looking pattern and thus something like 8 towers had to be read. Using the same telephone dial someone else mentioned we had to cycle through a dozen numbers and write them down...in theory, every hour near the top of the hour. Most often they were done once a shift by more 'experienced' ops. And twice a day the pattern change...what a rigmarole. No single button to push. (We were warned it could blow up the transmitter!) Shut off the signal...dial 3 or 4 numbers to change to night or day pattern....then turn the signal back on. Then do readings again and compare with previous one to indicate which towers were on or off or at lower power.
All these daily sheets we were told, were sent to Ottawa where some department read thru them to verify that we were following regulations. Several years later, during a building cleanout, boxes and boxes of these readings sheets were discovered at the back of a storage room. Ottawa, indeed. I recall several occasions when going in to op a Sunday morning show, the pattern was still on daytime and had been all night. The previous evening's op (weekend=part-timer / newbie, of course] had not done it properly. We never lost our license that I know of.

NW · October 25, 2019 6:17 am

RadioActive wrote:
potentiometer wrote:
@ zed. It could be apocryphal, but I heard CHYR actually changed call letters when it moved up the dial and became CHIR. I always thought that was very clever since they could still call themselves, "CHEER."
It's not a myth. That actually happened. The Leamington station had two sets of call letters, CHYR at 710 and CHIR at 730. They also had two licences with the different calls. The outlet moved to FM in 1993.

I honestly can't recall another AM radio station anywhere in North America with this kind of odd frequency switching arrangement, but it did allow them to be on the air 24 hours a day. Although I'll bet they never got the chance to use that old radio cliche slogan, "Don't Touch That Dial!"

As usual, YouTube provides the proof.

And if you listen carefully you can an ID fro WVIC East Lansing MI (now WVFN) just before CHYR recommences on 730.

zed · October 25, 2019 7:50 am

In 1968 CJCS Stratford was 500 watts by day and 250 at night with a single tower just south of the city. The station signed off overnight, so as the morning announcer I would flip the switch to turn the station on at 5:58 am. In the spring/ summer months the power up time was 6:30 so I would just sign on with daytime power UNTIL a complaint came in from a ship on Lake Erie. There were really no consequences for me personally that I recall.

mace · October 25, 2019 8:31 am

RA: A truly fascinating and interesting topic [at least to radio geeks like me]. Since I started DXing in 1965, I was always aware of pattern changes and why they were necessary. I had no idea of what was involved in the actual process. I just assumed someone turned a knob or pushed a button to go from day to night pattern. In their Top 40 days, CHUM and CKFH usually did their change while a song was playing. CFRB had one of the cleanest and quickest changes I have ever heard. Unless you knew what to listen for, most people would never notice a change had been made.

tvguy · October 25, 2019 9:23 am

Great stuff folks. My recollection may be a bit hazy after nearly 50 years, but when I worked the board at CFRB in the late 60's early 70's I believe that the operator had to manually change pattern. I seem to recall a "button" to be pressed I think it was on the McCurdy board. The pattern change time was on the log, which we had to initial. The board op was responsible to try and avoid interrupting the announcer and paid spots, when he/she made the change. if I recall correctly and some former RB engineers out there could clarify, there were (electro) mechanical relays at the tower site that took a second or two to engage and change the tower config. I assume that automation came later in the 70's or 1980's and the pattern change could interrupt program content.. I also remember that the TX control for CKFM when it was transmitting from the old bank of commerce building, was at the rear of the studio, and it was fairly primitive. That tower and the antennas would ice up during the winter which usually required an engineer or tech to head down to the site and manually deal with the problem on-site. A few years later, De-icers on Commerce Court West, and a new advanced control panel alleviated the FM antenna icing issues.

Last edited by tvguy (October 25, 2019 9:23 am)

WindsorWatcher · October 25, 2019 2:46 pm

WNZK-AM licensed to Dearborn Heights, Mich., in metropolitan Detroit, operates on 690 daytime and moves to 680 at night. It mostly carries ethnic programming. The achievement of directional signals using a number of towers is a fascinating topic but also highly technical.

Last edited by WindsorWatcher (October 25, 2019 2:50 pm)

pinto · October 25, 2019 4:28 pm

https://en.wikipedia.org/wiki/Clear-channel_station

The Foxer · October 27, 2019 10:59 pm

Hi RA,
Before I ever started in the TV biz, my very first broadcasting gig was at CFPA 1230 radio in Thunder Bay. I was the 6 to 12 jock 6 days a week and for added pleasure also worked Sundays from 3:30 to midnight, what a joy. But being 21, and my first job in the biz, the harsh reality of life dropped on my head: the power change that I missed several times and did not get fired for it. Imagine 1,000 watts day, 250 night, omni pattern protecting some other rinky dink station across Lake Superior. The control was like a phone dial, you had to dial in some numbers, then flip a toggle switch and look at the meter on the control panel.
I think 1,000 watts got as far as Kekabekka Falls and 250 just barely reached the airport. Old man Parker, who owned the station was also the engineer who advised me of the notices from the DOC.