"WKOX, Newton"

[dumber than a box of hair]

For both WRCA and WKOX. the SAME CP that permitted construction of the new facilities granted a change in the CoL. And the reason for the CoL change was the inability of either station to meet the coverage requirements for its old CoL from the new site. So when it issued STAs allowing operations from the new site to commence, the FCC must also have said that the CoL changes were then in effect. Both WRCA and WKOX promptly changed their legal IDs as soon as they started broadcasting from the new site. I do not believe this was a coincidence. I suspect that if you can find the authorizations to begin operation (under STA) from the new site, you will see that the authorizations also mention the CoL change. You appear to be saying that the FCC did not have to issue the notice that the CoL change would be effective with the start of operations from the new site, but why would it not be when both the facilities change and the CoL change were authorized by the same CP and the reason for the CoL change was the facilities change?

The CoL change is contained in the CPs for both daytime and nighttime, but you cannot commence operation for a new AM directional until the FCC grants program-test authority. Assuming they have, that's when it would kick in...but ID'ing as Newton also contradicts the legal-ID rule, which says nothing about operation under a CP or a PTA with a different CoL. The CoL on the license is still Framingham.

But...this wouldn't be the first time the FCC has contradicting rules.

 

[Laurence Glavin]

Does anyone know if the many AM's that identify their City of License as New York can do that even though there must be parts of the five Boroughs whe their signals fall short...and this MAY apply to 50 kilowatters too.

 

[fybush]

Does anyone know if the many AM's that identify their City of License as New York can do that even though there must be parts of the five Boroughs whe their signals fall short...and this MAY apply to 50 kilowatters too.

They are, for the most part, grandfathered under an older version of the rules that required 25 mV/m over the center of the community (usually defined as the main post office) instead of 5 mV/m over the entire community.

Of the AMs licensed to New York, I'm guessing only the biggest of the big guns - 660, 710, 770, 880 - put a solid 5 over all five boroughs at night. 1010 might do so after its upgrade, as may 1130. 1050 and 1560 almost certainly fall short, and none of the lower-powered signals (570, 820, 1280, 1330, 1380, 1480, 1600) come close.

 

[DanStrassberg]

Does anyone know if the many AM's that identify their City of License as New York can do that even though there must be parts of the five Boroughs whe their signals fall short...and this MAY apply to 50 kilowatters too.

They are, for the most part, grandfathered under an older version of the rules that required 25 mV/m over the center of the community (usually defined as the main post office) instead of 5 mV/m over the entire community.

Of the AMs licensed to New York, I'm guessing only the biggest of the big guns - 660, 710, 770, 880 - put a solid 5 over all five boroughs at night. 1010 might do so after its upgrade, as may 1130. 1050 and 1560 almost certainly fall short, and none of the lower-powered signals (570, 820, 1280, 1330, 1380, 1480, 1600) come close.

1050 may cover all five boroughs well enough to not require a waiver. Staten Island is kind of behind the pattern, but it's close enough (especially to 1050's proposed new site) and the conductivity is good enough that the 50-kW signal might cover the entire borough. The other four boroughs should be no sweat even with the substantial nighttime QRM from CHUM. I believe that 1190, which is 10 kW-D/30 kW-N and has a night pattern that thows a null over the southeast Bronx and northern Queens (to protect long-dark CHTN) still manages to cover something like 83% of the population of the five Boroughs--meaning it meets the CoL coverage requirements for New New York City with 3% to spare. WOWO, despite now being nulled toward New York at night. still sends a surprisingly potent skywave to the east. WLIB's NIF, to which WOWO must be the sole contributor, is in the mid to high teens.

 

[DanStrassberg]

We'll have to see what the signal is like when they finally get to operate at 50 kW. During the STA period. except when actual prrof-of-performance measurements are being made, WKOX is restricted to 10 kW-D and 1 kW-N--same powers as they used in Framingham.

I stand by the above statement, BUT I heard something while listening briefly to WKOX early this morning that may (or may not) be a bad omen for the quality of nighttime reception once the station increases to the full 50 kW-U. What I heard sounded like the dreaded "phasing" phenomenon, which occurs when an AM station's high-angle skywave is reflected back to earth within the normal nighttime groundwave coverage area. The result is often referred to as a "short-wave" effect--that is audio that becomes badly distorted for many seconds, then clears up for a while only to become badly distorted again a few seconds later. If you've ever heard recordings of short-wave broadcasts from Europe or Africa during Word War II, you know what I'm talking about. Those broadcasts were transmitted by short wave and they have that characteristic sound.

On AM, the best way to minimize phasing is to use a half-wave transmitting antenna, which minimizes high-angle skywave. At AM frequencies, half-wave towers are tall and therefore are not liked by neighbors or municipal authorities that have to grant building permits. Half-wave towers also cost more to build and maintain than do shorter ones. And since they are taller than 200', half-wave towers for medium-wave stations must be illuminated, which adds to their construction cost and requires paying ongoing electric bills for the energy that keeps the lights on.

For all of these reasons, the WKOX/WRCA/WUNR five-tower site in Newton uses towers just shorter than 200', which is less than 1/4 wavelength at 1200. Electrically speaking, 85-degree towers are not at all uncommon. Most likely, nearly half of the AM stations in the US use towers that are no taller than 85 degrees. Signals from such towers are not regarded as being subject to unusual phasing problems. But that WKOX should possibly be experiencing bad phasing at a distance of less than nine miles from its site and ~90 degrees away from its radiation minimum is not a good early sign.

Once WKOX is running the full 50 kW, my location will be either just inside or just outside of the station's 13.<something> mV/m NIF contour. Normally, I don't think phasing should be expected to be a significant problem at such a location. Right now, though, while WKOX is running only 1 kW at night, the signal I get here is only about 1.8 mV/m. 1200 is a noisy channel here in the northeast and there certainly is a lot of noise under WKOX's night signal. Could the problem be the result of the interfering signals (CFGO, WTLA, WAGE, and others)? Definitely! But it didn't sound to me as if that was the case. I'll guess I'll just have to wait for the real (50 kW) thing.

However, nighttime-reception reports from others would be welcome. Just be sure to tell us when and where you were listening.

 

[Eli Polonsky]

Once WKOX is running the full 50 kW, my location will be either just inside or just outside of the station's 13.<something> mV/m NIF contour. Normally, I don't think phasing should be expected to be a significant problem at such a location. Right now, though, while WKOX is running only 1 kW at night, the signal I get here is only about 1.8 mV/m. 1200 is a noisy channel here in the northeast and there certainly is a lot of noise under WKOX's night signal. Could the problem be the result of the interfering signals (CFGO, WTLA, WAGE, and others)? Definitely! But it didn't sound to me as if that was the case. I'll guess I'll just have to wait for the real (50 kW) thing.

I'd imagine that once they get the 50 kW going that any phasing area will be farther outside of greater Boston in your direction.

 

[DanStrassberg]

I'd imagine that once they get the 50 kW going that any phasing area will be farther outside of greater Boston in your direction.

In theory, the entire system is linear. You increase the power by 50 times and the groundwave increases by sqrt(50) and the reflected skywave also increases by sqrt(50). If the theory is correct, then, the areas of phasing would be unaffected by the power increase. I don't believe that there is anything other than anecdotal evidence to suggest that the theory is wrong, but there certainly are a lot of people who believe that phasing gets worse as you increase power and hence that the theory is wrong. Few of those who believe that phasing gets worse at higher power realize that they are implicitly postulating a nonlinear system, but that's what they are doing.

Guy-wire top loading could increase the effective height of the towers at 1200 to about 114 degrees. I believe that at 112 degrees, the vertical radiation pattern is supposed to be a perfect cosine function (IOW, a semcircle on a polar plot, in which the 90-degree axis represents the earth). Some stations have been built with 112-degree towers because the engineers apparently thought that some magic was associated with such a vertical pattern. Given that the installation is a triplex and given all the restrictions placed on the use of the site by the City of Newton, I don't know whether anyone involved would seriously consider top loading, but it might reduce the high-angle radiaition enough to be beneficial. However, if guy-wire loading could produce a worthwhile benefit, you'd think that WKOX's consulting engineers, duTreil, Lunden and Rackley, generally acclaimed as the world's foremost AM antenna designers, would have incorporated it in the design.