The future of AM radio
Sat Feb 2 07:26:08 EST 2008
Garrett: I think you are quite correct that WHDH would have arrived at
the same design for its array by considering the then-existing and
permitted co-channel Class IIs in the northeast as by considering only
KOA. It's also possible, I suppose, that WHDH had applied for its
power increase/Tx move before World War II and the FCC granted the CP
before the war but construction could not begin until 1946 or so
because of wartime restrictions (which prevented most station
construction for the duration of the war). So the CP for WHDH's
upgrade may have predated the other Class II CPs. However, if WHDH's
CP did not predate the other Class II CPs, weren't the FCC rules
regarding protection of existing stations, CPs, and applications
essentially the same then as they are now? That is, wouldn't WHDH have
been required to demonstrate in its application that designing to
protect only KOA would result in at least the required protections to
all of the then licensed, permitted, and applied-for Class IIs?
WJW is probably the key to the answer to this question. As suggested
by its its three-letter calls (dropped by the AM decades ago but still
in use, I believe, on TV), it is a very old station. But it may have
moved to 850 only a little before WHDH moved to Needham. Or if WHDH
applied to move to Needham before the war, WJW may have applied to
move to 850 AFTER WHDH applied to move to Needham but may have
completed construction of its 850 facilities before the US entered the
The history of such things is sometimes very difficult to establish.
Despite claims I've heard repeatedly that WHDH (in its 5-kW
incarnation in Saugus) was the first full-time US Class II on what had
been a de-facto Class IA channel, I believe that those honors
rightfully go to WPTF on 680. Both WHDH and WPTF were daytimers for
several years (because of KOA and KPO respectively), but I believe
that WPTF was licensed for night operation before WHDH was--and well
before WLAW (itself, originally a daytimer) even signed on.
US AM radio history---I love it!
Dan Strassberg (email@example.com)
----- Original Message -----
From: "Garrett Wollman" <firstname.lastname@example.org>
To: "Kevin Vahey" <email@example.com>
Sent: Saturday, February 02, 2008 12:41 AM
Subject: Re: The future of AM radio
> <<On Fri, 1 Feb 2008 22:00:34 -0500, "Kevin Vahey"
> <firstname.lastname@example.org> said:
>> For example when CINW took over the slot that CBM once occupied
>> they given an exemption since the station was the former CIQC
> It wasn't a new station, so there was no additional competition for
>> In theory couldn't the pattern be tweaked to allow the signal to
>> continue north while not in any way be beamed to the west and
>> southwest? I do know WEEI booms into Quebec City at night.
> Um, Quebec City is literally due north of WEEI.
> WEEI unaugmented night pattern, electric field at 1 km (mV/m)
> RMS = 2623
> min = 1.13 (at 277 degrees true, almost precisely toward KOA)
> max = 4168 (at 29 degrees true and again at 131 degrees true)
> The field at 0 degrees true (towards Quebec City) is 3298 mV/m.
> The null, loosely defined, is from 311 degrees true (approx. NW) to
> 221 degrees (approx. SW).
> KOA, as a class-IB station, would have required stronger protection
> than any of the class-II stations on 850, and I believe the pattern
> itself is clear evidence that the WEEI array was designed only to
> protect KOA, and the protection it gives to the other stations on
> channel is an artifact. (That is to say, at the time it was built,
> eliminating all of those stations from consideration would have
> resulted in an identical array design.)
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