WBZ morning signal skywave interference & 500kw speculation

[Mark Casey]

As happens maybe on a 1/3 of the mornings, from 0-3 hours after sunrise, 
this morning WBZ AM was (again) trashed by co-channel skywave just east of 
Springfield. It was still going at 8:30am.  WBZ does provide a low level, 
but somewhat listenable signal here during the day. But it gets interfered 
with many mornings. Even WTIC gets interference here, many mornings,  less 
than 25 miles from its transmit site!

For most the average (non-radio hobby person) folks the average day and 
night listenablity stops halfway between Worcester and Springfield, around 
Sturbridge. In fact, a Pennsylvania caller to Steve Lavelle's show 2 nights 
ago said she, jokingly, moved to PA, to get a better signal from WBZ. With 
the nightime signal at Sturbridge having Skywave fighting Groundwave, it's 
probably true. WBZ is still excellent, and, on average, the BEST nightime 
signal, in the area of Eastern North Carolina that I visit regularly.

The "what if" 500kw idea would still have to have been accompanied by an FCC 
policy of allowing less co-channel interference to be really effective. As 
it is now with WBZ's directional pattern, if you apply an ERP calculation 
(maybe one of the group can make a reasonably precise calculation), it is 
sending, effectively, at least 100kw toward the west. If WBZ had 500kw with 
the same pattern then you can guess the approx. ERP. But with the bad ground 
conductivity, I doubt it would have extended WBZ's listenable signal, for 
the average person, much past the MA/NY line. But, that would have been a 
big improvement. If the co-channel interference was lower than now, that 
still would have made WBZ a more regional station, covering most of the 6 
New England states with a decent signal.

I think that leaving the transmit site in Hull or a nearby location, away 
from residences, would have been a better choice than Provincetown. Signal 
degrade fast on land, and it would have been nice to have that loud, 
superstrong signal, that drowns out interference from traffic lights, bad 
electric transformers,  noisy computers and lights at every commercial 
corner, etc., even out at I495 and Worcester, Providence & Southern NH. The 
Hull (or area) site would provide that higher signal density, (as it does 
now) as the signal spreads out into expanding inland suburban and secondary 
market areas.

Absent the 500kw idea, what WBZ could have done , (or could do now) , would 
be to purchase several stations around New England to similcast its signal 
on.(50 kw directional 640-WNNZ would be one near perfect candidate, at least 
coverage-wise).

Mark Casey
K1MAP

----- Original Message ----- 
From: "Kevin Vahey" <kvahey@comcast.net>
To: "(newsgroup) Boston-Radio-Interest" 
<boston-radio-interest@bostonradio.org>
Sent: Wednesday, November 12, 2008 1:04 AM
Subject: What if WBZ had gone 500KW????


This discussion we have been having over AM in Europe makes me wonder
what if WBZ had gone to 500KW transmitting from Provincetown which was
being talked about 40 years ago.

What kind of daytime coverage could they have expected? I would think
500KW would have given a listenable signal as far south as
Philadelphia and north into Montreal.

Also were other clear channels trying to go to 500KW?