Trip to Phoenix

[Icangelp]

Thanks, Michael.

crainbebo. No KOMO, but in fairness, I didn't spend anywhere enough time on each frequency. Plus, I didn't get to do any sunset listening.

 

[jd]

1170 Spanish music station + KVOO

Ummm...I catch myself calling it that too! They should have never changed calls. How is "KFAQ" better than The Voice Of Oklahoma?

 

[davideduardo]

.
David: You mentioned the urban sprawl in Mexico City. It reminded me of WSB's tower site. How is the ground conductivity in that part of the world?

The AMs in Mexico City are almost all on the floor of the Valley of México, which is a dry lake bed. The soft, loamy soil has great conductivity, much like the central valley of California... the area from Sacramento to Bakersfield. I don't know if there are measurements, but based on the range of the lower power stations, I would guess the conductivity is in the 8 to 15 range.

The mountainous terrain surrounding the city is a different thing... volcanic rock, and not a good conductor. Most of the Sierra area of Mexico is lower in conductivity, like the area from Atlanta up to Bristol, TN. Coastal Mexico has good conductivity... and so on. In other words, intuition and a look at the terrain will give you an idea of how signals propagate.

 

[fybush]

Journal Broadcast Group had this bright idea that it would be a good idea to differentiate its AM and FM callsigns in markets where they'd been the same. It wasn't just KVOO(AM) becoming KFAQ - they did it in Wichita, too, where KFDI(AM) became KFTI.

 

[cyberdad]

.
David: You mentioned the urban sprawl in Mexico City. It reminded me of WSB's tower site. How is the ground conductivity in that part of the world?

The AMs in Mexico City are almost all on the floor of the Valley of México, which is a dry lake bed. The soft, loamy soil has great conductivity, much like the central valley of California... the area from Sacramento to Bakersfield. I don't know if there are measurements, but based on the range of the lower power stations, I would guess the conductivity is in the 8 to 15 range.

According to a very general Atlas of ground conductivity that I was looking at, conductivity around Mexico City is a 10....which I'm sure is an approximation. But assuming that's accurate, your estimate is spot on. Best conductivity (30) appears to be chiefly in the coastal northeast.

 

[michael hagerty]

I just took a 15 mile drive from North Phoenix to downtown (9:15-9:45 PM local time) and KGO came in like a local. Better than most locals, in fact. Only minor electrical interference in stretches with a lot of fluorescent signs. I wonder if they were on reduced power or off the air when you tried them?

KDWN was audible too, but weak.

 

[Icangelp]

I noticed that there are a lot of Apps and CPs for AM stations around Tucson.

I wonder how many are active and will actually happen.

 

[davideduardo]

According to a very general Atlas of ground conductivity that I was looking at, conductivity around Mexico City is a 10....which I'm sure is an approximation. But assuming that's accurate, your estimate is spot on. Best conductivity (30) appears to be chiefly in the coastal northeast.

Does your Atlas include just North America or the whole world. I'd love to know the conductivity estimates for Quito (Pichincha Province) and Guayaquil (Guayas Province) in Ecuador, where I had stations.

 

[Icangelp]

According to a very general Atlas of ground conductivity that I was looking at, conductivity around Mexico City is a 10....which I'm sure is an approximation. But assuming that's accurate, your estimate is spot on. Best conductivity (30) appears to be chiefly in the coastal northeast.

Does your Atlas include just North America or the whole world. I'd love to know the conductivity estimates for Quito (Pichincha Province) and Guayaquil (Guayas Province) in Ecuador, where I had stations.

David.

You've probably seen this, but...

http://hamwaves.com/antennas/gnd-sigma/vlf_mf_ground_conductivity_atlas.pdf

 

[cyberdad]

I've been absent from the board for a few days (family stuff), but fortunately Icangelp stepped in. Indeed, this was the ground conductivity atlas I was referring to.

 

[Icangelp]

I've been absent from the board for a few days (family stuff), but fortunately Icangelp stepped in. Indeed, this was the ground conductivity atlas I was referring to.

It is a very interesting document. Thanks for mentioning it.