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Is KRDC 1110 am los angeles shutting down on the 22nd?

My recollection is from the late '70s. It seemed like I was in the middle of the LA freeway system heading east. It was perfect reception and I must have assumed it was the same anywhere within line of sight of the tower. Thank you for clearing this up for me.
Remember that freeways are not typical. They tend to have no surrounding obstructions, and many of them are elevated above the level of surrounding streets. That's a perfect FM reception location.

On the other hand, if you take the 210 going W/NW, you find much of it is below surrounding levels, and it is fairly close to the mountains. So FM signals are harder to get, particularly the ones that don't "get around the curve" in that freeway as it hugs the hills. The 10 and the 60 are the opposite... nice open FM reception.
 
Remember that freeways are not typical. They tend to have no surrounding obstructions, and many of them are elevated above the level of surrounding streets. That's a perfect FM reception location.

On the other hand, if you take the 210 going W/NW, you find much of it is below surrounding levels, and it is fairly close to the mountains. So FM signals are harder to get, particularly the ones that don't "get around the curve" in that freeway as it hugs the hills. The 10 and the 60 are the opposite... nice open FM reception.
Thank you for pointing that out! Something I noticed about AM was that stations often went farther than expected, which I attributed in part to the fact that the mountains were far enough away, to allow the signals to escape. I know that there's also ground conductivity to consider and something about the heat that I can't recall. In any case, I could hear KHJ clearly for hundreds of miles and KFI all the way to San Jose!
 
Something I noticed about AM was that stations often went farther than expected, which I attributed in part to the fact that the mountains were far enough away, to allow the signals to escape.
It was surprising when I found out that with the right combination of ground conductivity, power, and frequency, a groundwave station can max out around 1,200 miles (WWVB on 60khz covers much of the US during the daytime, and @cyberdad apparently can get CBK 500 miles away in Lethbridge).
By contrast, FM can go on infinitely, but anything that gets in the signal's way will harm the reception, and there is a lot for the FM signal to get lost in,
I know that there's also ground conductivity to consider and something about the heat that I can't recall.
I was also surprised to learn that to some extent, AM does bend around hills, allowing it to cover farther this way, but an excessive amount of mountains can block the signal. I actually heard the opposite if what you did: The colder the weather, the better the signal travels. Supposedly, the ideal temperature for MW is close to absolute zero.
In any case, I could hear KHJ clearly for hundreds of miles and KFI all the way to San Jose!
I'm glad you got to enjoy KFI at that distance before all the noise took over :).
 
Back before the noise floor rose, KFI had an amazing signal---in fact, they even had a jingle about it. The YouTube post is wrong---these are from 1969:

That's some pride in your signal! Did they legitimately say New Mexico!? (or was it To Mexico) Thanks for sharing, this was delightful!
 
It was surprising when I found out that with the right combination of ground conductivity, power, and frequency, a groundwave station can max out around 1,200 miles (WWVB on 60khz covers much of the US during the daytime, and @cyberdad apparently can get CBK 500 miles away in Lethbridge).
By contrast, FM can go on infinitely, but anything that gets in the signal's way will harm the reception, and there is a lot for the FM signal to get lost in,
FM goes in a straight line, in the air. It can not bend with the horizon but AM can as it is not airborne in the daytime.
I was also surprised to learn that to some extent, AM does bend around hills, allowing it to cover farther this way, but an excessive amount of mountains can block the signal. I actually heard the opposite if what you did: The colder the weather, the better the signal travels. Supposedly, the ideal temperature for MW is close to absolute zero.
AM does not bend. It is conducted in the local area by the ground itself. Each type of terrain has different “ground conductivity” and signals cover best in the rich loamy soil of the Great Plains and worst in the sans of deserts or sandbars like Long Island, NY. Rock is poorer than soil, so AMs seem to sneak around mountains when really the signal is just looking for the best path.

Signals tend to do better in winter as there is less static in the atmosphere to interfere.
 
Signals tend to do better in winter as there is less static in the atmosphere to interfere.
I forgot about that point, thank you.
AM does not bend. It is conducted in the local area by the ground itself. Each type of terrain has different “ground conductivity” and signals cover best in the rich loamy soil of the Great Plains and worst in the sans of deserts or sandbars like Long Island, NY. Rock is poorer than soil, so AMs seem to sneak around mountains when really the signal is just looking for the best path.
That is intriguing how the signal does that, almost like lightening finding the best path to the ground, right? It was crazy having the likes of WNAX coming in at 300+ miles when I went to Rapid, the conductivity must be amazing up there. Since you're here, I did notice that along US 34 near Estes Park, a strong signal can kind of quiet down (not turn to static, but just get real quiet, like what happens when you pass under a bridge) and then pop back up later. Is this also caused by what you mentioned about the signal sneaking?
 
Back before the noise floor rose, KFI had an amazing signal---in fact, they even had a jingle about it. The YouTube post is wrong---these are from 1969:

In the 1970s & 1980s, I used to pick up KFI on a regular basis (barely) just north of San Francisco (about 400 miles north of L.A.), but only when I was right near the Bay.
 
In the 1970s & 1980s, I used to pick up KFI on a regular basis (barely) just north of San Francisco (about 400 miles north of L.A.), but only when I was right near the Bay.
You're talking daytime? Because at night, in the late 70s and early 80s, they were loud and clear in Ukiah and Reno.
 
You're talking daytime? Because at night, in the late 70s and early 80s, they were loud and clear in Ukiah and Reno.
Yes, sorry I wasn't more specific. That was daytime reception of KFI. At night of course KFI always came in well in the Bay Area. However, XEPRS 1090 at night was even stronger, due to their directional 50kw from Mexico aimed straight at Los Angeles and San Francisco.
 
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Yes, sorry I wasn't more specific. That was daytime reception of KFI. At night of course KFI always came in well in the Bay Area. However, XEPRS 1090 at night was even stronger, due to their directional 50kw from Mexico aimed straight at Los Angeles and San Francisco.
Indeed, 1090 from Baja can be heard underneath at night within 10 miles of Seattle's 1090. Must be nice to have an ERP of 200 kW.
 
Indeed, 1090 from Baja can be heard underneath at night within 10 miles of Seattle's 1090. Must be nice to have an ERP of 200 kW.
I can hear XEPRS up here in central Alaska every night, pretty darn strong some times, but KFNQ Seattle is usually under it most of the time
 
I can hear XEPRS up here in central Alaska every night, pretty darn strong some times, but KFNQ Seattle is usually under it most of the time
What's interesting is that XEPRS can be heard well at night thousands of miles away, yet the signal is hard to hear just 50 miles east of San Diego.
 
What's interesting is that XEPRS can be heard well at night thousands of miles away, yet the signal is hard to hear just 50 miles east of San Diego.
That was the case for the now-departed KMIK 1580, licensed to Tempe AZ but their transmitter was in Mesa. They were heard in Australia but not in much of the east valley (including most of their COL) of metro Phoenix at night. They were 50 kW day and night running Radio Disney. Like many Ancient Modulation stations, the land the towers sat on was worth more than the station itself.

It's now KQFN, a Class D sports station running 50 kW days and 95 watts nights from north-central Phoenix. They need two FM translators to cover the north and east valley, where the money is. If they weren't the local Westwood One affiliate that carries NFL games, they'd be completely worthless.
 
What's interesting is that XEPRS can be heard well at night thousands of miles away, yet the signal is hard to hear just 50 miles east of San Diego.
XEPRS apparently has a figure eight NNW/SSE pattern that hugs the Pacific coast, with a deep null ENE. The pattern has been known to be out of whack at times in the past; in the early 1980’s I would sometimes find it booming into the Texas panhandle. I remember the “XPRS Los Angeles” jingle.
 
That was the case for the now-departed KMIK 1580, licensed to Tempe AZ but their transmitter was in Mesa. They were heard in Australia but not in much of the east valley (including most of their COL) of metro Phoenix at night. They were 50 kW day and night running Radio Disney. Like many Ancient Modulation stations, the land the towers sat on was worth more than the station itself.

It's now KQFN, a Class D sports station running 50 kW days and 95 watts nights from north-central Phoenix. They need two FM translators to cover the north and east valley, where the money is. If they weren't the local Westwood One affiliate that carries NFL games, they'd be completely worthless.

When i lived in Laramie Wyoming (far SE corner) KQFN was a regular visitor right before sunset power down. This is how well I heard it sometimes:

 
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