670 Question

[radioman148]

Here in the Chicago area WSCR was off the air between 2 and 3 AM. I heard a country station coming from the west.
I checked Colorado, but all I saw on Radio Locator was a Christian talk in that state. Anyone know what I was hearing?

 

[semoochie]

Here in the Chicago area WSCR was off the air between 2 and 3 AM. I heard a country station coming from the west.
I checked Colorado, but all I saw on Radio Locator was a Christian talk in that state. Anyone know what I was hearing?

If this were 30 years ago, I would say definitely KBOI but since they're News/Talk, anything is possible.

 

[gar hi]

I did some Googling and found this. It's called ....

"The All New Caddo Country
Playing REAL Country Music"

KHGZ Radio

http://caddocountryradio.com/

But according to the AM station info search site, they are listed as daytime only.

Maybe they are now broadcasting at night with their new format?

 

[radioman148]

KHGZ fits what they were playing, but the direction I was receiving it from was more to the west. I guess it will remain a mystery until or unless I hear it again.

 

[Schroedingers Cat]

Rich, doesn't a 78.5 degree antenna give you more than 285 mV/m @ 1 km for 1 kW? It looks like it was authorized under the nominal power rules. Licensed in 1984.

Sounds like testing or forgetting to turn off the AM when the FM translator continues unlimited time.

 

[rfry]

doesn't a 78.5 degree antenna give you more than 285 mV/m @ 1 km for 1 kW? ...

It depends on the number and length of the buried radials (and assuming that they all are in good condition).

A 78.5-deg monopole driven against 120 x 90-degree buried radials has a theoretical IDF of 298.4 mV/m at 1 km for 1 kW of applied power.

The same monopole driven against 90 x 78.5-degree buried radials has an IDF of 279 mV/m at 1 km for 1 kW.

 

[frankberry]

The depth of the radials comes into play as well. For the highest efficiency, they should be buried close to the surface .... making them a prime target for copper thieves (unfortunately).

 

[davideduardo]

Rich, doesn't a 78.5 degree antenna give you more than 285 mV/m @ 1 km for 1 kW? It looks like it was authorized under the nominal power rules. Licensed in 1984.

Has anyone ever tested what happens to the field strength in different directions when a there are shorter radials on part of the site? Or when there are more radials to one "side" of the tower than in another? In other words, can the number, placement and length of the radials have a directionalizing effect on such a facility?

 

[gar hi]

KHGZ fits what they were playing, but the direction I was receiving it from was more to the west. I guess it will remain a mystery until or unless I hear it again.

I've found that judging exact direction is not as easy as it may seem.

For the longest time when I was in Florida, I thought New York was in a specific direction from within the place I lived but I later found out that it was actually quite a few degrees east of where I automatically was aiming the radio.

 

[rfry]

Has anyone ever tested what happens to the field strength in different directions when a there are shorter radials on part of the site? Or when there are more radials to one "side" of the tower than in another? In other words, can the number, placement and length of the radials have a directionalizing effect on such a facility?

Here is a NEC4.2 analysis of such an installation, for the conditions shown.

 

[davideduardo]

Here is a NEC4.2 analysis of such an installation, for the conditions shown.

Thank you. That's very informative.

When I owned stations in Ecuador, I considered trying to steer the non-directional single tower radiation towards the population center. When the money comes from your own pocket and a mistake could be costly, one goes with proven standards. Since I had no access to computer modeling in the 60's and my math and engineering abilities were nothing stellar, I never tried it... now I am glad I did not.

 

[Pat3]

It was coming in gangbusters in central mississippi for a while last night. I think they forgot to turn the transmitter off. It's listed at 5000 watts daytime only Glenwood, Arkansas. It used to be "Hog Sports"

 

[radioman148]

It was coming in gangbusters in central mississippi for a while last night. I think they forgot to turn the transmitter off. It's listed at 5000 watts daytime only Glenwood, Arkansas. It used to be "Hog Sports"

Thanks Pat. That seems to solve the mystery based on your location.

 

[CTListener]

One of you ought to send them a reception report and see if you get a verification letter or card back.

 

[radioman148]

One of you ought to send them a reception report and see if you get a verification letter or card back.

Good idea. I just might do that.

 

[semoochie]

Has anyone ever tested what happens to the field strength in different directions when a there are shorter radials on part of the site? Or when there are more radials to one "side" of the tower than in another? In other words, can the number, placement and length of the radials have a directionalizing effect on such a facility?

It seems to me that if the radials aren't installed correctly or fall into disarray, that tower wouldn't be as efficient as it should and that would affect the directional signal. I would think that would have more effect than intentionally using shorter(or longer)radials. Then again, I'm not an engineer.

 

[Schroedingers Cat]

Rich, did any stations you know of ever use fewer radials to use nominal power levels (usually 1000 or 5000) rather than series limiting resistors or reduced input under older rules to squeeze in with less inverse field? There are still plenty of stations that use the old licensed nominal power levels.

 

[frankberry]

There are two reasons why this is not good engineering practice.
An antenna system with fewer radials may not meet FCC minimum antenna efficiency requirements.
Without an adequate ground system, the base impedance of the tower would likely change every time it rained.

 

[rfry]

Rich, did any stations you know of ever use fewer radials to use nominal power levels (usually 1000 or 5000) rather than series limiting resistors or reduced input under older rules to squeeze in with less inverse field?

None that I know of, sorry.

 

[radioman148]

Again early this morning WSCR was off and this time I confirmed it was KHGZ. The signal faded some, but when it was on the upswing it was pretty strong. Also, it was nice to hear WFAN nice & strong with WSCR and their IBOC off.