Re: Toronto AMs

[Dan Strassberg <dan.strassberg@worldnet.att.net>]

At 12:17 PM 9/8/98 -0400, you wrote:
>Leave it to Dan to provoke me to do this...
>
My last visit to Rochester was YEARS ago (the relatives who used to live
there are now long dead). Maybe you can figure out how long ago it was from
the following information. (I can't.) On that trip, the 680 daytimer in
Rochester had moved to 990 not so long before. I think (but am not sure)
that 990's six-tower array was on the air. I know that 990 operated with
lower power, either ND or from a simpler array, for a fairly long time
before the six-tower array was complete. 680 in Toronto was running 50
kW-D/25 kW-N DA-2, but from your description of the current signal, it
doesn't sound as if the TX was in its present location. The signal in
Rochester and quite a way south was very good both day and night.

Moreover, I remember listening to 680 somewhere around Syracuse and hearing
Toronto and Binghamton duking it out for quite a long distance along the
Thruway. From all of this, I inferred that 680 was transmitting from the
north shore, southwest of Toronto and that the day pattern must have been
shaped to just give Binghamton the necessary protection at the north end of
its coverage area. (In other words, Toronto's rate of change of signal
strength with azimuth was very high, suggesting a very complex array.) Now,
WINR has just gotten its long-sought CP for 5 kW-D. For sure, back then,
extending the coverage area to the north would have been impossible because
of overlap with Toronto. Come to think of it, how can the as yet unbuilt 670
in Syracuse coexist with 680 in Binghamton?

I have a WTOR coverage map. The signal strength along the lake shore in
downtown Toronto is just 5 mV/m. A few miles inland, the signal strength
drops off to 2 mV/m. If the signal is truly better in downtown Toronto than
CBL's, there really is something wrong with the CBL/CJBC site.

And how come you didn't include the Hamilton 820? I don't recall the day
pattern, but the night pattern is a teardrop aimed due north. With 50 kW-U,
820 should get into at least the western part or the Toronto metro well enough.

As for 1250 and 1320 sharing an array, I guess that this means that metro
Toronto may not just be the home of more complex AM directionals per square
km than any other place on the continent, it's must also be the home of the
most complex AM antenna-coupling networks. I was told that the rule of thumb
for diplexing was that the difference in the stations' frequencies must
exceed 10% of the higher frequency. I know this was violated decades ago
whrn 560 and 610 in San Francisco were diplexed (and had problems that were
never really resolved). You don't find too many diplexed pairs that are as
close as those were, but 1250 and 1320 are closer percentage-wise. I
calculate that 70 kHz is 5.3% of 1320. So maybe there is hope for WKOX and
WADN diplexing after all. 80 kHz is 6.67% of 1200 kHz.

On that score, the best deal for WKOX would seem to be to use the WADN site
at night only. WKOX should stay put during the day and use the two existing
towers (diplexed with WJLT and WRPT) to produce a modified cardioid with
radiation equivalent to 10 kW to the southwest and close to 100 kW to the
northeast. The towers are taller than WADN's and they're top-loaded besides,
so the effect would be a signal equivalent to almost 100 kw from the WADN
site. Actually, the signal would be equivalent to much more than 100 kW from
the WADN site, because the WADN site abuts a gravel pit on the west and
south. Gravel must have all of the conductivity of the streets of Manhattan.
Still, 50 kW at night from E Acton would be better than 1 kW from Framingham.

- -------------------------------
Dan Strassberg (Note: Address is CASE SENSITIVE!)
ALL _LOWER_ CASE!!!--> dan.strassberg@worldnet.att.net
(617) 558-4205; Fax (617) 928-4205

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End of boston-radio-interest-digest V2 #175
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