If you look over the list of original Class I-A and I-B stations in the U.S. and Canada, four do not run 50,000 watts around the clock: 990 CBW Winnipeg, 1550 CBE (now CBEF after switching from CBC's English network to its French network), 1560 KNZR Bakersfield and 1570 CKOO Oshawa.
As Class I-B stations, CBE and KNZR could have gone 50,000 watts but they never did. CBE stayed at 10,000 watts and for many years KNZR had the same output, although in the 1990s, the owners (was it the Buckley Family, which also owned WOR New York?) did increase power to 25 kw by day, but remaining at 10 kw by night. I suppose by the 90s, it was too late for KNZR to go the full 50,000 watts.
Why did CBE and KNZR never go to the maximum power when they had the opportunity, in the earlier days of AM radio? Were the owners too cheap to apply for the increase, or to build the necessary antennas and transmitter and pay the higher electric bill? All other U.S. and Canadian owners of Class I-A and I-B stations wanted the maximum power, even with the added costs.
A few months ago, we discussed why 990 CBW Winnipeg powers down slightly at night, going from 50 kw to 46 kw. Apparently CBW moved its antenna a few years back, probably closer to the U.S. border. To protect other stations on 990, CBW reduces power slightly after sunset, even though CBW is an original I-A station.
And CKOO Oshawa was originally on 1350, running 10,000 watts. But when the CBC started moving some of its AM stations to FM, including original Class I-A 1570 CBJ Chicoutimi, CKOO moved to 1570 and inherited CBJ's protections. 1570 is a much less crowded frequency than 1350, so even at 10 kw, CKOO's signal has less interference from other stations. But because Oshawa is only about 30 miles from Toronto, CKOO could not increase to 50 kw as CBJ used to run from its location in rural Quebec.
As Class I-B stations, CBE and KNZR could have gone 50,000 watts but they never did. CBE stayed at 10,000 watts and for many years KNZR had the same output, although in the 1990s, the owners (was it the Buckley Family, which also owned WOR New York?) did increase power to 25 kw by day, but remaining at 10 kw by night. I suppose by the 90s, it was too late for KNZR to go the full 50,000 watts.
Why did CBE and KNZR never go to the maximum power when they had the opportunity, in the earlier days of AM radio? Were the owners too cheap to apply for the increase, or to build the necessary antennas and transmitter and pay the higher electric bill? All other U.S. and Canadian owners of Class I-A and I-B stations wanted the maximum power, even with the added costs.
A few months ago, we discussed why 990 CBW Winnipeg powers down slightly at night, going from 50 kw to 46 kw. Apparently CBW moved its antenna a few years back, probably closer to the U.S. border. To protect other stations on 990, CBW reduces power slightly after sunset, even though CBW is an original I-A station.
And CKOO Oshawa was originally on 1350, running 10,000 watts. But when the CBC started moving some of its AM stations to FM, including original Class I-A 1570 CBJ Chicoutimi, CKOO moved to 1570 and inherited CBJ's protections. 1570 is a much less crowded frequency than 1350, so even at 10 kw, CKOO's signal has less interference from other stations. But because Oshawa is only about 30 miles from Toronto, CKOO could not increase to 50 kw as CBJ used to run from its location in rural Quebec.
. You are correct that the station used to be on 1350. I used to drive by their towers all the time on business trips where I'd make the run between Toronto-Ottawa and Toronto-Montreal on a regular basis. Just north of the Lake Ontario shore southeast of town. I never heard them here in the Chicago area when they were on 1350, but on 1580, they're pretty much a regular.