George Mather was an excellent "old school" engineer.  Somehow they bought a dumpy motel on Lakeshore Road and the land was a long rectangle. Mather figured out how to cram a six tower parallelogram array into that narrow strip.  That's what accounts for the 60 degree spacing of the north-south towers (normally around 90 degrees). Two towers were almost at the edge of Lake Ontario, and the ground system had to be run into the lake. The other brilliant part of the design is that the major lobe pointing to Toronto had much of the path over water. The conductivity of Lake Ontario is quite high CHUM was consistently stronger than CFRB because of that.
And to think that the patterns were probably hand-cranked using a slide rule (no personal computers in 1962, and not much in the way of time-share).
The night pattern remains unchanged to this day.
The referenced chimney I think was at St. Lawrence Cement, and I believe it was subsequently detuned with a wire skirt.
With regard to all the back and forth with various Canadian and American consultants, the shoe was on the other foot in 1970 when CFRB added two 550 foot towers and removed two of the shorter towers.  Now there are four 550 footers.
It's amazing the expense to which all these stations CHUM, CHFI-AM, and CKEY went in the quest of the holy grail of 50 kW.  Legend has it that the original nine tower CHFI patterns on Burnhamthorpe Road were tuned using helicopter measurements as well, and it took months.  The day power was only 1 kW at the outset.

Fifty kilowatts was indeed the holy grail for some AM stations, especially the ones in big cities. If applied properly 50 KW would give the station more signal strength to overcome noise and interference. It also gave the station some 'bragging rights' about the big signal.

Some stations resorted to multi-element arrays with 8, 9, or 10 towers that made the signal pattern very directional and allowed the 50 KW signal without causing problems for others on that frequency. Sometimes the pattern put most of the signal over an unoccupied areas or lake. Many of these stations had to drop to 1 kilowatt or less at night. These tower arrays were relatively expensive to erect and maintain and required quite a bit of property. There are a couple of stations from Detroit that fall into this category. 1200 KHZ is one of them I believe. Another was / is WFLI 1090 Lookout Mountain, Tennessee.

At the end of the process, yes these guys could run 50 KW but given the costs versus the improvement in signal there was little utility in doing it.

FWIW, with respect to 1050 CHUM and living in Kitchener through the 60's and 70's, CHUM had a decent signal with its 10KW through the day, but we lost it at night. I don't know when CHUM went to 50 KW but I never detected any improvement in the signal.

And then there is ground conductivity. But that is a different subject.
 

Last edited by darcyh (October 19, 2023 12:35 pm)

Living in the K/W area back in the mid 70's, CFTR on 680 always came in louder and clearer than 1050 CHUM.  Not that CHUM was poor or anything but TR had a better signal, even at night with more bottom end than CHUM.  1050 was fine in the Guelph/Fergus area but weaker by the time you got to K/W.

Living in London in the 80's CFTR also was available in the daytime but with a weaker signal.  However London and area had a lot of good radio, so there really wasn't much need to tune in out of market stations anyway. 

Last edited by paterson1 (October 19, 2023 1:45 pm)

When I was growing up, hardly ever listened to CKFH.  It didn't really reach where I was living, even with 50,000 watts.  Always remember it having a noisy weak signal. 

Evenings I didn't really listen to the radio much unless in the car.  Spent my time watching TV after dinner, or out with friends.  Even back then, most radio listening was in the car.  My mother had the stereo on in the house all the time.  Tuned into CFRB in the morning, and then CKFM or CFCA, sometimes CHFI the rest of the day. 


 

CHUM was ahead of its time in selecting Jordan Harbour, considering that CFTR, CFGM/CHOG/CFYI/C... etc, CKEY/CKYC/CJCL all ended up in Niagara to beam across the lake! And of course if CHUM did get 100 Kw, everybody else would have been clamouring for it. Also, the line in the CFTR app about there being nothing beside the Grimsby transmitter site is ironic, considering there are condos there now.