[BC] Directional Antenna Proofs

[James B. Potter]

Rene:  

Are you talking about WFIL AM 560?  I worked there in the then-new round
building back in college in the late 1960s for Irv Ross, and over at WHAT &
WWDB down the street for Bob Hoy. Don't know whatever became of either of
them.  BTW, I often cite WFIL Famous 56 as having an exemplary signal
compared to my 560 here.  I lived in Abington (suburb of Phila) when I was a
kid, and we could carry WFIL all over the place, particularly to the Jersey
Shore.  Never had any signal problems north, east, south or west with WFIL.
That 3-tower in-line array did a fantastic job. Pretty much the same with
the old WIBG nee WZZD AM 990, although their pattern was sharp and went away
at sunset.  

I do contract engineering work for KWTO AM 560 here in Springfield, MO.  Our
directional pattern protects you, among others.  I have the same problem
with coverage complaints, but I think they are legit.  Long time residents
claim KWTO got down into Arkansas, but no longer.  They have listened to
Rush for years on KWTO, and now they can hardly hear him.  And they're
right.  Heck, it's weak into Branson, just 26 miles south.  We're checking
the array for obvious problems, but none in evidence at this point. Other
consultants have encouraged me to believe that nationwide the ground
conductivity isn't what it used to be, and some are petitioning the FCC for
power increases to bring the fields back to their original specs.  I may do
that in my case here. Even if noise weren't a factor, on some higher-end
radios I test at the neighbors and relatives around the signal is still weak
and distant sounding.  We're pumping 5,350 Watts into a 4-tower directional
array fully modulated and compressed to around 125%.  It's not blistering
the paint off the walls far off the property in Ozark. 

Noise, however, is a serious culprit.  In my house 23 miles southwest of my
560 array, I can barely hear it on various consumer table-top clock radios
in the house. A considerable amount of hash and grunge up and down the band.
Last night I brought my trust FIM home and took it into the bedroom and
tuned it to 560 near my clock radio.  Guess what? I had a good 2.6 mV and
very quiet!  Looks like the noise comes into those cheapie radios through
the utility power line, also.  Now what?

Regards/Jim Potter

 

-----Original Message-----

 From: Rene Tetro

Exactly!

I went through a standard "the signal isn't as good as it used to be"
discussion with my general manager a while back, so I did a partial proof.
The numbers were within 1-2% of the original proof (some a point or two
higher, some a point or two lower).  The signal was essentially the same as
it had been when constructed in 1997.

Even with the proof in hand some staffers still insisted there was a problem
with the antenna system, the transmitter, or both.

I agreed with them in principle that the station's coverage was not what it
had been even a few years ago.  It was obvious -- and impossible to deny.
But, it took a lot of convincing to get them to finally believe that the
listenable coverage area had deteriorated, not because of antenna or
transmitter issues, but because the noise level is so dramatically worse.  

I finally convinced them with a very simple test:  I had them drive around
and tune their car radios to a "quiet" frequency (the term quiet being a bit
of a misnomer in this case) and listen.  It didn't take long before people
realized that the noise was the culprit.  Traffic light controllers, dirty
power lines, computer/microprocessor generated auto noise, etc, etc, were
obvious when tuned between stations.

Rene'

Rene' Tetro
WFIL-WNTP
Philadelphia

-----Original Message-----

 From: Dave Dybas

 
...what I have found is that the noise level on the AM Band has increased
significantly and makes reception difficult. We can blame that noise
increase on the advent of the microprocessor and other modern digital
technology.