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Re: A favor

Garrett: I know nothing about the areas of high and low population density
in and around Rahlee, Durrm, and Hah Pawnt. I do know that WPTF is a really
old station and I assume that its TX site is a lot older than most of the
residences in that area. Maybe the population just deployed itself in areas
that happen to lie in WPTF's nulls. As you well know, that phenomenon has
affected many hundreds (maybe thousands) of AMs in the US.

I guess that those self-supporting towers are really sturdy--perhaps because
they are so fat. The towers have been replaced (in some cases more than
once) at most sites of that age. I think it's a curiosity that WPTF does not
use its 122-degree day tower as part of its night array. Lord knows, there
are plenty of two-tower arrays in which the towers are of unequal height.
Using towers of unequal heights complicates the engineering a bit--and
probably complicated it quite a bit in the pre-computer age when WPTF built
its site, but there are a bunch of OLD arrays that use towers of unequal
heights. So the calculations weren't a mystery.

I have no way of getting information on the location of the day tower
relative to the night towers. Conceivably, a more favorable night pattern
could be synthesized by using all three towers. Of course, WPTF is now quite
well hemmed in. There are few directions in which it could improve its night
signal without increasing interference to some station built long after WPTF
but that now requires protection.

Dan Strassberg, dan.strassberg@att.net
eFax 707-215-6367

----- Original Message -----
From: Garrett Wollman <wollman@khavrinen.lcs.mit.edu>
To: Ron Bello <RBello@BelloAssoc.com>
Cc: Boston Radio Mailing List <bri@bostonradio.org>
Sent: Tuesday, October 14, 2003 11:15 PM
Subject: Re: A favor

> <<On Tue, 14 Oct 2003 22:28:08 -0400, Ron Bello <RBello@BelloAssoc.com>
> > Twice in the last week when leaving a relative's home,
> > trying to listen to the Red Sox game after sundown
> > there was virtually no signal for WEEI on the northern
> > side of Sudbury on route 27.
> Interesting.  Where I live in Framingham, pretty much on the
> Needham-Denver axis, the 850 signal is quite serviceable.  (Certainly
> by comparison to the 680 signal which at times is totally trashed.)
> The 850 night field in the direction of Acton is about eight times
> what it is toward me, but Acton is also about twice as far away, so
> Kevin's informant should be getting twice the signal, although that
> direction is on the cusp of the nighttime null.  (WYLF is a
> well-known offender.)
> Just for kicks I ran the 680 signal as well.  Acton is deep in 680's
> western null as well.  In fact, if you drew a line straight through
> the 680 towers that extended for 11.1 miles, you'd end up at the 1120
> site.  My location is just a few degrees off the axis of WRKO's
> pattern min, which explains their awful signal at night.  WRKO
> protects only WPTF and KNBR at night, and WPTF protects WRKO and
> KNBR.[1]  (WRKO's night null is quite broad.)  Looking at WPTF's night
> pattern now, I can't understand why it was built where it was; the
> night signal misses large parts of the market.  Perhaps it was put
> there to simplify the DA design.  Dan?
> -GAWollman