AM 760 no longer 50kw at night?

[Mark Roberts]

Yes, the fault is called "San Andreas". This is also an issue with 830 AM in the LA market, also on the wrong side of another (but smaller) fault line. I have looked several times for studies... even doctoral papers... about fault line effects on groundwave propagation, but never found anything.

I have wondered about that, and the effects in the Bay Area with our multiple faults (geologic, not political) - I live a little more than a mile from the Hayward fault (which had three earthquakes this morning!) and have wondered whether some San Francisco and Peninsula stations have a slightly weakened signal than they otherwise would have as a result. The fault that basically runs under Interstate 680 in the Tri-Valley is another one of interest to me.

 

[TomásEstefan]

No, there was no common ownership. Lotus only entered the Northwest in recent years. They bought 4 Boise FMs in 2018, and have no AM interest there. KBOI was bought by Citadel in 2001, and in 2011 Citadel merged with Cumulus.

IIRC, the 670 site was in open land near Littlerock.

Ah, Littlerock I knew it had to be in the Antelope Valley area.

AM 760 is one of a few San diego stations I've heard from 2700 miles away

However, 760 is rare.. only heard it twice. Here's one, its the best of the two times: https://drive.google.com/file/d/137uWtLCKXmvXRaECJ28SuXBrws7GI8JA/view?usp=share_link

I've heard XEKAM 950 several times and pretty decently, XEPE 1700

and before the tower fell, XEPRS was in nightly. averaging from fair to blowing the doors off like a local.

I have wondered about that, and the effects in the Bay Area with our multiple faults (geologic, not political) - I live a little more than a mile from the Hayward fault (which had three earthquakes this morning!) and have wondered whether some San Francisco and Peninsula stations have a slightly weakened signal than they otherwise would have as a result. The fault that basically runs under Interstate 680 in the Tri-Valley is another one of interest to me.

I have previously mentioned this on another thread, and I know David will remember, but If you take a drive up HWY 14 from Santa Clarita toward Palmdale and the Antelope Valley, as an example, a moderately strong LA station such as KABC 790 sounds pretty decent as you travel up the fwy and might even seem to get a little stronger as you increase in elevation as you go over Escondido Summit which is over 3000 ft , as you head NE through Acton the station still sounds good, and it's still good as you approach the rim of the AV. But as you actually enter the AV and approach and cross the SA Fault line which is easily identifiable, the station "takes a dump" at that point and never recovers as you drive N toward Lancaster. As you said David, it seems strange that there
has never been any kind of formal study of this odd phenomenon.

 

[davideduardo]

I have previously mentioned this on another thread, and I know David will remember, but If you take a drive up HWY 14 from Santa Clarita toward Palmdale and the Antelope Valley, as an example, a moderately strong LA station such as KABC 790 sounds pretty decent as you travel up the fwy and might even seem to get a little stronger as you increase in elevation as you go over Escondido Summit which is over 3000 ft , as you head NE through Acton the station still sounds good, and it's still good as you approach the rim of the AV. But as you actually enter the AV and approach and cross the SA Fault line which is easily identifiable, the station "takes a dump" at that point and never recovers as you drive N toward Lancaster. As you said David, it seems strange that there
has never been any kind of formal study of this odd phenomenon.

And the most interesting thing is that the Lancaster / Palmdale are as well as that around Santa Clarita are all in the LA radio market.

"The metro area population of Lancaster-Palmdale in 2022 was 517,000, a 2.58% increase from 2021. The metro area population of Lancaster-Palmdale in 2021 was 504,000, a 2.65% increase from 2020. The metro area population of Lancaster-Palmdale in 2020 was 491,000, a 2.94% increase from 2019."

Lancaster-Palmdale Metro Area Population 1950-2023

Chart and table of population level and growth rate for the Lancaster-Palmdale metro area from 1950 to 2023. United Nations population projections are also included through the year 2035.

www.macrotrends.net

That is around 5% of the metro population... in itself, as large as the Ventura/Oxnard market and ranked about 125th in the whole country.

 

[Signal Geek]

In the olden days when KHJ was still at their original site at Fairfax and Venice, the daytime ND signal in the West Valley was strong, their nighttime signal was fair. However when they moved the facility to Alvarado St in Echo Park, the daytime signal is fair but night time is really bad, weak with lots of co-channel. The ground conductivity at that site is awful...

Maybe so, but KHJ comes in pretty well at night here in San Diego. They're probably still throwing some of their signal south.

 

[davideduardo]

Maybe so, but KHJ comes in pretty well at night here in San Diego. They're probably still throwing some of their signal south.

They throw nearly all the signal southwards. That has not changed at all.

 

[TomásEstefan]

They throw nearly all the signal southwards. That has not changed at all.

When I was a kid I used to visit the Oceanside Pier with my family, I noticed on a couple of occasions that among some of the people fishing and listening to the radio, a few more seemed to be tuned to "93 KHJ" than "136 KGB" . Later I would realize that a combination of great personalities and a good dial position, besides a good signal would be key. From our place in Oceanside, KGB's daytime signal was clearly stronger than KHJ and played the same music, but by comparison KGB was near the top part of the dial and for some folks probably "not major market". They sounded good to me but what did I know?

 

[semoochie]

When I was a kid I used to visit the Oceanside Pier with my family, I noticed on a couple of occasions that among some of the people fishing and listening to the radio, a few more seemed to be tuned to "93 KHJ" than "136 KGB" . Later I would realize that a combination of great personalities and a good dial position, besides a good signal would be key. From our place in Oceanside, KGB's daytime signal was clearly stronger than KHJ and played the same music, but by comparison KGB was near the top part of the dial and for some folks probably "not major market". They sounded good to me but what did I know?

Then there's KCBQ.

 

[TomásEstefan]

Then there's KCBQ.

There sure was. I always felt there was a kind of symbiosis between KCBQ and KRLA (1110) back in the day...

 

[boombox4]

Yes, the fault is called "San Andreas". This is also an issue with 830 AM in the LA market, also on the wrong side of another (but smaller) fault line. I have looked several times for studies... even doctoral papers... about fault line effects on groundwave propagation, but never found anything.

Wouldn't a fault line affect groundwave propagation, depending on whether the bedrock or soil was different either side of the fault line?

And if there were different ground conductivity on each side of the fault line, would that make a difference?