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WSB getting trashed from Canada

cyberdad

cyberdad

Moderator
Staff member
Startling development this morning here about 90 minutes before sunrise....

On 750, WSB was getting absolutely pounded by another signal of nearly equal strength. It turned out to be CKJH "Classic Hits 750" obviously on 25KW day pattern. The night pattern shows a null squarely in the direction of Atlanta. But in this case, they were solid for about 15 minutes before I had to step away to shower/shave. I'm not sure what's going on, but if you've never heard this one, you might want to give it a try.
 
Well I could never hear that at my house. I am only 5 miles from WSB's transmitter.
 
CKJH is loud here when conditions are good to the east. 'CK750' with classic hits. With all of the stations occupying 750 here in the west, WSB is practically impossible.
 
I checked in to 750 this morning again about two and a half hours before sunrise. WSB was back on top and sounding good. BUT during a couple of fades CKJH came through on top for about a half-minute or so. Even when WSB came back, CKJH, was audible underneath.

I'm not quite sure what may be going on. Conditions to the northwest were very good pre-dawn this morning. In addition to CJKH, CKLQ, CFRY, CFAM, and CFAC were all in. CKLQ was on top of WCBS (very rare) and CFRY was a flat-out monster.
 
A Virtual Trip To WSB

https://www.fybush.com/sites/2005/site-050204.html
Their transmitter building is surrounded by a shopping center. (This area is littered with shopping centers.) When I first arrived in Atlanta in 1981 this area was a grassy knoll. About 1984 the station got the idea to build a shopping center on the property. When the parking lot was being built, particular attention was paid to not disturb the station's ground system.
It is roughly located at I-285 and the LaVista Road intersection.
 
kf4rca said:
https://www.fybush.com/sites/2005/site-050204.html
Their transmitter building is surrounded by a shopping center. (This area is littered with shopping centers.) When I first arrived in Atlanta in 1981 this area was a grassy knoll. About 1984 the station got the idea to build a shopping center on the property. When the parking lot was being built, particular attention was paid to not disturb the station's ground system.
It is roughly located at I-285 and the LaVista Road intersection.
Click to expand...

I would be concerned that a parking lot would seal out moisture from the ground radials, drying out the soil and rendering the grounding system ineffective. However, I guess I cannot complain about their massive footprint - they were my test station in Daytona Beach. If I could get WSB, it was a good radio. If not - pass on it. And I received it daytime in Lubbock, TX on two occasions separated by six months, using a five foot loop. So they really get out there! Too bad the local ground conductivity in Atlanta is so poor - you have this monster signal and it shoots right past its intended market because there is no local return path. Taking a GE Superadio and a portable folding loop up Stone Mountain is still on my bucket list - to see what reception is like with ZERO ground conductivity!
 
There was a time in the 80's when AM stations were rethinking their strategies. Music had gone to FM. And talk radio was not viable due to the Fairness Doctrine being in effect. So, stations were looking at alternative forms of revenue. The huge expanse of land at a major intersection seemed perfect for a shopping center. Besides, who knows, AM may be a thing of the past in 30 years or so. But when the Fairness Doctrine was abolished in '87, that was the shot in the arm that AM needed. And along came Limbaugh, Hannity, and others.
Like most AMs, they really don't care about their DX audience. The rely on a stable of local clients to finance their operation. And the shopping center income isn't bad either.
 
Talk radio existed before the Fairness Doctrine. Rush Limbaugh had a show in 1984 where he pretty much did what he did later.
 
gr8oldies said:
Talk radio existed before the Fairness Doctrine. Rush Limbaugh had a show in 1984 where he pretty much did what he did later.
Click to expand...

Yes, and in 1976, KABC was #1 in LA, with about two share points more than #2 KBIG (Arbitron, Spring, 1976). WOR was #2 in New York City, just a point behind WABC.
 
rbrucecarter5 said:
I would be concerned that a parking lot would seal out moisture from the ground radials, drying out the soil and rendering the grounding system ineffective.
Click to expand...

It's not as simple as that. Hopefully Schroedinger's Cat and RFry will add to or correct my meager understanding but...

There are quite a few instances of AM sites that are paved over or built upon. As long as the radials maintain mechanical integrity and proper grounding of structures with steel frames is adhered to, there is not going to be much difference in the coverage.

There are plenty of anecdotes of station owner "watering" around the tower base in dry parts of the year, and such activities don't seem to make any difference. In fact, having the surface sealed likely keeps ground moisture trapped under the pavement in dry spells.

An example of a "dry" ground system is the counterpoise system of KTNQ in Los Angeles. A warehouse complex was built there, and the ground system is at about 20' above ground, even spread as a web over parking areas. There is no soil, wet or dry, under the counterpoise. And there was no degradation of the signal.

Think of an AM system like a dipole, with the ground system being the "other" half of the antenna. The fact that a Franklin antenna, which is two center-fed stacked half-wave towers, is a dipole and does not need much of a ground system proves this; ground conductivity determines how well a signal will propagate in an entire geographic area. Of course, a station wants to locate its tower where conductivity is best, but, again, that is because the entire area or region will benefit the reception of the signal.
 
Other Thoughts

DavidEduardo said:
... KTNQ in Los Angeles. ... the ground system is at about 20' above ground, even spread as a web over parking areas. There is no soil, wet or dry, under the counterpoise. And there was no degradation of the signal.
Click to expand...

Elevated radials behave differently than buried ones.

The r-f current source for a set of wires elevated above the earth and used as a counterpoise for a base-fed, monopole radiator consists of a hard-wired connection to the transmitter r-f ground terminal. A monopole using a set of 4 to 6 elevated, horizontal radial wires can equal the performance/efficiency of one using a conventional set of 120 x 1/4-wave wires buried in the earth.

The r-f currents flowing on buried radials result from the fields radiated by the monopole into the earth within a 1/2-wave radius of the tower base. Those currents need to be collected by the buried radials, and delivered back to the r-f ground terminal of the transmitter. The sum of those currents equals the r-f current able to flow on (and radiate from) the monopole itself.

... The fact that a Franklin antenna, which is two center-fed stacked half-wave towers, is a dipole and does not need much of a ground system ...<snip>
Click to expand...

The elemental parts of sectionalized, vertically-oriented MW radiators such as the 180/180 Franklin and its variations are each end fed, in phase, and often with different powers radiated by the two sections. This permits increasing the gain in the horizontal plane while reducing skywave radiation above 45 degrees elevation or so, compared to a 195 degree monopole. This can reduce the nighttime self-interference area, and move it further from the transmit site. OTOH, the two sections of a center-fed dipole are fed 180 degrees out of phase.

The belief that a Franklin antenna does not need a ground plane such as needed for MW monopoles may be based on thinking of the Franklin as some kind of a balanced radiator. Balanced radiators don't need or use a ground plane. But the co-linear sections of a Franklin antenna are unbalanced radiators, and need a good r-f ground for the same reason that a single monopole needs one.

_________

PS: Has anybody seen any posts from Schroedinger's Cat in the past 3-4 months? I haven't, and I miss them.
 
rfry said:
Elevated radials behave differently than buried ones.

The r-f current source for a set of wires elevated above the earth and used as a counterpoise for a base-fed, monopole radiator consists of a hard-wired connection to the transmitter r-f ground terminal. A monopole using a set of 4 to 6 elevated, horizontal radial wires can equal the performance/efficiency of one using a conventional set of 120 x 1/4-wave wires buried in the earth.

The r-f currents flowing on buried radials result from the fields radiated by the monopole into the earth within a 1/2-wave radius of the tower base. Those currents need to be collected by the buried radials, and delivered back to the r-f ground terminal of the transmitter. The sum of those currents equals the r-f current able to flow on (and radiate from) the monopole itself.



The elemental parts of sectionalized, vertically-oriented MW radiators such as the 180/180 Franklin and its variations are each end fed, in phase, and often with different powers radiated by the two sections. This permits increasing the gain in the horizontal plane while reducing skywave radiation above 45 degrees elevation or so, compared to a 195 degree monopole. This can reduce the nighttime self-interference area, and move it further from the transmit site. OTOH, the two sections of a center-fed dipole are fed 180 degrees out of phase.

The belief that a Franklin antenna does not need a ground plane such as needed for MW monopoles may be based on thinking of the Franklin as some kind of a balanced radiator. Balanced radiators don't need or use a ground plane. But the co-linear sections of a Franklin antenna are unbalanced radiators, and need a good r-f ground for the same reason that a single monopole needs one.

_________

PS: Has anybody seen any posts from Schroedinger's Cat in the past 3-4 months? I haven't, and I miss them.
Click to expand...

Thank you for the vastly improved explanation of Medium Wave radiators. I learned something new from your post (I had always heard that a Franklin was "center fed" because of the end-point feed between the two sections. While that explains the appearance, it obviously it does not explain the electrical behavior.

The explanation of traditional buried grounds vs. counterpoise was most enlightening.

I have not heard from Schroedinger's Cat, either. I miss his very informative posts, particularly when they correct my rather deficient engineering knowledge!
 
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