I live approx 80 miles from the xmitter of station WABC (New York) 50,000
watts. During the day my reception is good-to-very good. After sunset
however, the signal is poor to unlistenable -- due to fading and man-made
QRM. The stations night-time signal is directional but I live in the
direction of the major lobe. The station advertises covering 27 eastern US
states at night -- which I don't doubt.

I can receive a Boston station (WBZ, 50k watts) and a Charlotte, NC station
(WBT, 50k watts)at night loud and clear. Both of these hundreds of miles
from me. (Also get WJR in Detroit and WLS in Chicago loud & clear.)

I seem to be in a "shadow" for the relatively close WABC. I'm using a high
quality (Sangean) table radio with a built-in ferrite loop antenn. Any
suggestions for improving my WABC night time reception??

Dave Pitzer
=======================================

"Dave Pitzer" wrote in message
...
I live approx 80 miles from the xmitter of station WABC (New York) 50,000
watts. During the day my reception is good-to-very good. After sunset
however, the signal is poor to unlistenable -- due to fading and man-made
QRM. The stations night-time signal is directional but I live in the
direction of the major lobe. The station advertises covering 27 eastern US
states at night -- which I don't doubt.

I can receive a Boston station (WBZ, 50k watts) and a Charlotte, NC
station
(WBT, 50k watts)at night loud and clear. Both of these hundreds of miles
from me. (Also get WJR in Detroit and WLS in Chicago loud & clear.)

I seem to be in a "shadow" for the relatively close WABC. I'm using a high
quality (Sangean) table radio with a built-in ferrite loop antenn. Any
suggestions for improving my WABC night time reception??

Dave Pitzer
=======================================
Dave

I'm curious about a similar situation. in California. Are you able to
receive the stations equally well, or poorly, with the radio oin a car at
this location?

Jerry

Don't they reduce power at night fall to prevent interference with other
stations
Art
"Dave Pitzer" wrote in message
...
I live approx 80 miles from the xmitter of station WABC (New York) 50,000
watts. During the day my reception is good-to-very good. After sunset
however, the signal is poor to unlistenable -- due to fading and man-made
QRM. The stations night-time signal is directional but I live in the
direction of the major lobe. The station advertises covering 27 eastern US
states at night -- which I don't doubt.

I can receive a Boston station (WBZ, 50k watts) and a Charlotte, NC
station
(WBT, 50k watts)at night loud and clear. Both of these hundreds of miles
from me. (Also get WJR in Detroit and WLS in Chicago loud & clear.)

I seem to be in a "shadow" for the relatively close WABC. I'm using a high
quality (Sangean) table radio with a built-in ferrite loop antenn. Any
suggestions for improving my WABC night time reception??

Dave Pitzer
=======================================

Not these stations. They are so-called "clear channel" stations.

DP
============

" wrote in message
news:%pfTc.147043$eM2.107369@attbi_s51...
Don't they reduce power at night fall to prevent interference with other
stations
Art
"Dave Pitzer" wrote in message
...
I live approx 80 miles from the xmitter of station WABC (New York)
50,000
watts. During the day my reception is good-to-very good. After sunset
however, the signal is poor to unlistenable -- due to fading and
man-made
QRM. The stations night-time signal is directional but I live in the
direction of the major lobe. The station advertises covering 27 eastern
US
states at night -- which I don't doubt.

I can receive a Boston station (WBZ, 50k watts) and a Charlotte, NC
station
(WBT, 50k watts)at night loud and clear. Both of these hundreds of miles
from me. (Also get WJR in Detroit and WLS in Chicago loud & clear.)

I seem to be in a "shadow" for the relatively close WABC. I'm using a
high
quality (Sangean) table radio with a built-in ferrite loop antenn. Any
suggestions for improving my WABC night time reception??

Dave Pitzer
=======================================

On Sat, 14 Aug 2004 03:11:55 GMT, "
wrote:

Don't they reduce power at night fall to prevent interference with other
stations
Art

Hi Art,

Historically, three letter calls in the AM band were designated as
"clear channel" stations and are generally always lit up at full
power. "Clear channel" was meant to serve a vast region out of major
metropolitan centers. KVI is one here in Seattle, KGO in San
Francisco, WGN & WLS in Chicago, KOA in Denver, KFI & KNX in Los
Angeles, WSM in Nashville, WWL in New Orleans, WBZ in Boston, WHO in
Des Moines, KYW in Philadelphia (strange listing) and so on. Almost
across the board all transmit 24/7 at 50KW with omnidirectional
antennas. Not all three letter calls are clear channel, what with the
change of time and market and financial backing.

73's
Richard Clark, KB7QHC

"Bill Turner" wrote in message
...
On Fri, 13 Aug 2004 22:27:48 GMT, "Dave Pitzer"
wrote:

I live approx 80 miles from the xmitter of station WABC (New York) 50,000
watts. During the day my reception is good-to-very good. After sunset
however, the signal is poor to unlistenable -- due to fading and man-made
QRM. The stations night-time signal is directional but I live in the
direction of the major lobe. The station advertises covering 27 eastern
US
states at night -- which I don't doubt.

I can receive a Boston station (WBZ, 50k watts) and a Charlotte, NC
station
(WBT, 50k watts)at night loud and clear. Both of these hundreds of miles
from me. (Also get WJR in Detroit and WLS in Chicago loud & clear.)

I seem to be in a "shadow" for the relatively close WABC. I'm using a
high
quality (Sangean) table radio with a built-in ferrite loop antenn. Any
suggestions for improving my WABC night time reception??

Dave Pitzer
=======================================


__________________________________________________ _______

I have the same situation here in California. I'm about 100 miles from
KFI, another 50 kW station, and during the day reception is a bit weak,
but adequate. Come sundown however, reception begins fading and is very
distorted. The reason is that the groundwave portion of the signal is
still present, but is now being interfered with by the skywave portion,
which is not present during the day. If I were to move farther away,
out of groundwave reception, the signal would become much clearer, but
only at night. During daytime it would not be heard at all.

It doesn't matter whether I'm using a home or car radio, the effect is
the same. At night, the clearest stations here are from the San
Francisco area about 400 miles away, but they are inaudible during the
day

One help (which I do use at home) is to listen using an SSB receiver.
The internal BFO in the receiver inserts the sometimes-missing carrier
and improves things a lot, but still not perfect. There are some
high-end shortwave radios available which can be set to work this way
and the improvement is considerable.

Outside of that, using only a radio, not much can be done unless you
want to try diversity reception using automatically switched antennas.
At BCB frequencies this takes lots of real estate since the antennas
have to be separated quite a bit to be effective.

If you want to skip the radio completely (at home) and you have high
speed internet access, many radio stations have streaming audio
available. I suppose in time this will be available in cars too.

--
Bill, W6WRT
QSLs via LoTW


This would account for the strange undulating "out of phase" sound -- with
the ground and sky waves canceling and reinforcing in a random manner.

Seems to me that there is not much use having 50k watts if the signal in the
station's market area is virtually unlistenable. Then again, most of the
commercials at night are "national", not "local".

DP
================

"Jerry Martes" wrote in message
...



"Dave Pitzer" wrote in message
...
I live approx 80 miles from the xmitter of station WABC (New York)
50,000
watts. During the day my reception is good-to-very good. After sunset
however, the signal is poor to unlistenable -- due to fading and
man-made
QRM. The stations night-time signal is directional but I live in the
direction of the major lobe. The station advertises covering 27 eastern
US
states at night -- which I don't doubt.

I can receive a Boston station (WBZ, 50k watts) and a Charlotte, NC
station
(WBT, 50k watts)at night loud and clear. Both of these hundreds of miles
from me. (Also get WJR in Detroit and WLS in Chicago loud & clear.)

I seem to be in a "shadow" for the relatively close WABC. I'm using a
high
quality (Sangean) table radio with a built-in ferrite loop antenn. Any
suggestions for improving my WABC night time reception??

Dave Pitzer
=======================================
Dave

I'm curious about a similar situation. in California. Are you able to
receive the stations equally well, or poorly, with the radio oin a car at
this location?

Jerry

Hmmmmm.... haven't tried that. The use of a non-directional "whip" (car)
antenna might actually help to seriously attenuate the ground wave yet
"grab" the sky wave.

AM BCB DXing in a car/truck at night is a popular hobby I understand.

DP
==============

DP
=========

"Bill Turner" wrote
I have the same situation here in California. I'm about 100 miles from
KFI, another 50 kW station, and during the day reception is a bit weak,
but adequate. Come sundown however, reception begins fading and is
distorted. The reason is that the groundwave portion of the signal is
still present, but is now being interfered with by the skywave portion,
which is not present during the day. If I were to move farther away,
out of groundwave reception, the signal would become much clearer,
but only at night. During daytime it would not be heard at all.
______________

Various types of "anti-fade" radiators are used by many of the 50kW stations
to try to minimize this effect.

There is a tradeoff in the electrical height of the usual AM broadcast
transmit antenna between producing the greatest groundwave and generating an
excessive high angle skywave that can interfere with that groundwave at
night.

A 225 degree vertical is about optimum for groundwave, but has a high angle
lobe that can cause this type of interference problem. A 195 degree
vertical has less groundwave but little/no high angle lobe, and so is used
by many full time 50kW stations. WJR, Detroit is an example of a station
using a 195 degree vertical (700 foot guyed tower).

Other antenna types also have been used for this, such as the "Franklin,"
which is a sectionalized antenna with one vertical radiator above another,
each driven separately.

Note also that the carrier frequency of the station, the conductivity along
the groundwave path, and skywave propagation conditions will have an affect
on the location of this zone, and the extent of interference there.

R. Fry
(WJR staff engineer, mid 1960s)

Bill
Have you seen the homes they built at the base of KNX's tower? It makes
me wonder about how much tolerance we have to radiation.
Jerry

"Bill Turner" wrote in message
...
On Sat, 14 Aug 2004 03:11:55 GMT, "
wrote:

Don't they reduce power at night fall to prevent interference with other
stations

__________________________________________________ _______

KFI runs 50 kW, 24/7. I went on a tour of the site last year and if I
recall correctly, the only time they reduce power is during tours when
the tour group is at the base of the antenna, or when maintenance is
being done on the main antenna and they have to switch to the secondary
antenna. A fascinating tour, by the way. Take it if you ever have the
chance.

--
Bill, W6WRT
QSLs via LoTW

The sectionalized vertical antennas mentioned by Richard Fry appear to
have been, perhaps still are, frequently used in VK land where distances
are great. Makes for a serious antenna.
73 Mac N8TT

--
J. Mc Laughlin - Michigan USA
Home:

"Richard Fry" wrote in message
...

snip
Various types of "anti-fade" radiators are used by many of the 50kW
stations
to try to minimize this effect.

There is a tradeoff in the electrical height of the usual AM broadcast
transmit antenna between producing the greatest groundwave and
generating an
excessive high angle skywave that can interfere with that groundwave
at
night.

A 225 degree vertical is about optimum for groundwave, but has a high
angle
lobe that can cause this type of interference problem. A 195 degree
vertical has less groundwave but little/no high angle lobe, and so is
used
by many full time 50kW stations. WJR, Detroit is an example of a
station
using a 195 degree vertical (700 foot guyed tower).

Other antenna types also have been used for this, such as the
"Franklin,"
which is a sectionalized antenna with one vertical radiator above
another,
each driven separately.

Note also that the carrier frequency of the station, the conductivity
along
the groundwave path, and skywave propagation conditions will have an
affect
on the location of this zone, and the extent of interference there.

R. Fry
(WJR staff engineer, mid 1960s)