WITS/Red Sox

[markwa1ion@aol.com]

I appreciate Dan's well-thought-out comments.  Arlington is interesting 
because of the way two major hills (Turkey Hill and Belmont Hill a.k.a 
Wellington Hill) act to divide the town.  In the Arlington Heights 
shopping district (corner Park Ave. and Mass. Ave.) - which isn't high 
at all - signals from the south are reduced considerably by Belmont 
Hill - the peak of which is on the Arlington side of Route 2 at the 
Park Circle water tank.  This especially weakens Newton and Waltham 
area stations on the upper half of the dial, e.g. 1330, 1510, 1550, 
1600.  Also Turkey Hill blocks the route going a bit east of north, but 
there are no local stations in that direction: Lawrence on 800 would be 
the closest thing on that radial.  The station that really cooks in 
"the heights" is WRKO-680 which is closer to there than to other parts 
of town.  It travels down Lowell St. by the reservoir from the 
northwest over relatively low land "left of" (westerly of) Turkey Hill 
(and the minor "Gilboa Hill") blockage.

Arlington Center - Mass. Ave. at Pleasant St. - a mile or two to the 
east has less hill blockage and probably better soil conductivity, 
being fairly close to the Mystic River and Alewife Brook.  Most local 
stations are better there, especially those from Newton and Waltham 
that have a less-obstructed low-land ride along Route 60 at the bottom 
of the east flank of Belmont Hill.  Providence stations are also better 
in "the center" as compared to "the heights" (meaning the two shopping 
districts of Mass. Ave., neither of which is high).

Where I lived was halfway up the east side of Belmont Hill between the 
Pleasant St. and Park Ave. exits and something like 500 ft. north of 
the Route 2 centerline (Belmont-Arlington border).  This favored 
signals to the northeast, east, and southeast.  Stations to the west 
were at somewhat of a disadvantage.  The position looking eastward (and 
downward) towards Spy Pond, Fresh Pond, and the Alewife/Mystic valleys 
no doubt helped me to hear many AM broadcast band stations from Europe 
and Africa, especially once I got my hands on a Collins R-390A receiver 
a few years before 1974 when my parents sold the house and I had to 
move out.

Going back to the interference discussion: Implicit in all the careful 
analyses of how different stations' NIF contours are affected by other 
stations is the assumption that other stations, if not the sole source 
of interference to a given broiadcaster, are the principal thing to 
worry about.  Real-life listening tells anyone of even modest 
intelligence that things such as power lines, appliances, lighting, and 
computers take a far greater toll on station listenability.  Worrying 
about what KOA Denver (850) could do to WEEI Boston seems like a total 
joke compared to what the average overhead powerline could do in the 
mobile environment or the typical layout of digital gadgets could do in 
a home or office setting.  Add to that the effects of attenuation in 
the cement-and-steel-frame buildings many of us occupy a good portion 
of the day and it wouldn't matter a hill of beans if KOA deliberately 
ran full beef into a tight pattern aimed right at Boston.  The 
incremental added disablement of WEEI's signal would be insignificant 
compared to the effects of the aforementioned non-broadcast signal 
degraders.

Mark Connelly, WA1ION - Billerica, MA

<<
Well. When 1510 operated from Squantum, it was DA-1. So the 
inverse-distance
field to the north at 1 km was probably greater than WMKI's field by day
because WMKI is ND days, but maybe a bit less than WMKI's field to the 
north
at night. The 1260 night pattern (three towers), while producing a
relatively broad main lobe, produces a somewhat narrower lobe than did 
the
old 1510 two-tower DA-1 pattern (a modified cardioid with a fairly
substantial minor lobe to the south). Assuming equal antenna 
efficiencies
(probable), the pattern differences suggest a lower maximum for 1510 
than
for 1260. Add to that the greater attenuation vs distance at 1510 
compared
with 1260 (1510 is an ~20% higher frequency), and WMEX might easily 
have put
a signal 30% less than WMKI's into Arlington Heights. For your 
comparison,
though, you should use 02476, not 02474. From my understanding of the
location of your boyhood home, it is now in 02476, which is on the south
side of the bikeway (the old Boston and Albany RR right-of-way, north of
Mass Ave). 02474 is north of the bikeway. The population centroid of 
02474
is probably a mile north of the centroid of 02476.

My first home in Boston (June '56) was the MIT Graduate House (now 
Ashdown
House) at 300 Memorial Drive, Cambridge (corner of Mass Ave). On my 
Zenith
AM/FM table radio, a great set--eight tubes, IIRC--there were many 
nights
when WKBW and WTOP made WMEX unlistenable (except to a DXer) on that 
radio.
I'm sure that the signal at that QTH was substantially greater than 5 
mV/m.
However, I think you would have had to proceed down Mass Ave across 
Harvard
Bridge, through Back Bay, and well into the South End, before the signal
cleaned up enough to make for reliably good listening at night.

In those days, NIF calculations included only co-channel signals. For 
1510
in the northeast, that method of calculation was ludicrously inaccurate.
Historically, the situation with Boston vs Nashville on 1510 had only 
one or
two counterparts in the entire US--the Class A station protects a Class 
B
because the station of lower class (Boston) predates the Class A
(Nashville). (Another example: KIRO protects KSPN; that MIGHT be the 
only
other historical example.) Because of that protection, WMEX had, on 
paper, a
very low NIF--perhaps 2.5 mV/m or something close--probably lower than
WHDH's, which was likely in the 3s. Today's recalculated number, which
accounts for first-adjacent skywave, must be quite high. I could believe
north of 15 mV/m.

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

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