Local AM "Translator(s)" for a Local FM Station

[Kelly A]

I agree with what Mr. Berry said about AM transmitters requiring all of their power to achieve full modulation, however the fact remains that AM can just cover more miles.

That depends. Used to be an AM station would be receivable out to it's 1mVm contour. Now to overcome man made noise, it takes almost 15mVm to have an average receivable signal. I couldn't count the number of GM's convinced that some AM station signal has become degraded. After going through the process of a full proof, found out it's exactly as built many years ago. The noise floor in the AM broadcast band has gotten so bad that most stations at night have less than 25% of their original perceived coverage.

Kirk, you do have the right idea at heart, but implementing it in 2022 is kind of odd. However, you are always free to try it out on your own stations, or convince an AM to give it a try. Your strategy does have some basis in what others have done, but it hasn't been tried like this before! I'm a big fan of terrestrial radio (AM/FM), but I suspect it's time to give up on that, and even Sirius at this point.

The problem is; Kirk isn't taking into account any cost to benefit, especially considering that most people younger that 50, don't even know AM exists.

 

[michael hagerty]

That depends. Used to be an AM station would be receivable out to it's 1mVm contour. Now to overcome man made noise, it takes almost 15mVm to have an average receivable signal. I couldn't count the number of GM's convinced that some AM station signal has become degraded. After going through the process of a full proof, found out it's exactly as built many years ago. The noise floor in the AM broadcast band has gotten so bad that most stations at night have less than 25% of their original perceived coverage.


The problem is; Kirk isn't taking into account any cost to benefit, especially considering that most people younger that 50, don't even know AM exists.

I'm 66 and started listening to FM at 13---in 1969. If I hadn't been in radio starting at 15, and listening for professional reasons, I would likely never have dialed in an AM station after '69.

 

[kwthom]

<...>
Keep in mind that many AMs are only on the air because they need to be in order to have an FM translator. If that wasn't the case, many would most likely take their AMs dark and just keep the translator. Even then, many AMs have greatly reduced power so they aren't burning through $$ to feed a big transmitter when the only reason they keep the AM going is so they can have the FM translator(s).
<...>

Perhaps the OP needs some 'real-life' examples to help understand the fallacy in today's time with his concept:

Recently, an AM/FM translator was sold to a new group here locally. There's a thread in the Tucson, AZ forum on the station - KDRI. The FM translator is 250 watts, a few thousand feet above average terrain. It really sounds good here in the valley.

The AM is a 50k/1k blowtorch.

Radio-Locator.com

Radio Station Search Engine

radio-locator.com

It's safe to say it's covering 1/4 of the state, in the canyons that the signal can get through. For a few weeks after they came on the air, they were airing reports of the distant locations the AM was being heard.

So, does this facility have enough AM listeners to keep that 50k on during daylight hours?

https://ratings.****************/content/arb207

How much of that 3.3 is really listening on AM? 0.1?

 

[vchimpanzee]

I'm 66 and started listening to FM at 13---in 1969. If I hadn't been in radio starting at 15, and listening for professional reasons, I would likely never have dialed in an AM station after '69.

We didn't get an FM radio at home until the late 70s, or in the car until 1983.

I wouldn't call it listening, but in the early 70s I heard the beautiful music stations in businesses. In college I heard other people's radios, which meant mostly rock music.

 

[R.D.P.]

There's also a nighttime signal issue too. In Montgomery Alabama, as a bad example, the AM band is unlistenable after dark. I did a check not too long, while visiting there and discovered it. Their AM stations broadcast with 1000 Watts to less than that at night.​

Dan <><

 

[R.D.P.]

The noise floor in the AM broadcast band has gotten so bad that most stations at night have less than 25% of their original perceived coverage.

Preach on sir!

Dan <><

 

[ZantennaG1]

Recently, an AM/FM translator was sold to a new group here locally.

I hope they keep the oldies format!

There's a thread in the Tucson, AZ forum on the station - KDRI. The FM translator is 250 watts, a few thousand feet above average terrain. It really sounds good here in the valley.

I'm glad to hear that. Height really does matter when it comes to FM, and a few thousand feet can get you a wide sweeping signal, although I suspect Sentinel Peak Park and Drexel Heights probably gets poor reception. Nonetheless, that's all the more reason to allow FM's to increase their height and ERP to accommodate signals moved in from the AM band.

The AM is a 50k/1k blowtorch.

Radio-Locator.com

Radio Station Search Engine

radio-locator.com

I use an SDR on the west side of Phoenix to listen to it, and yep, KDRI is definitely good, and you can even hear KTNN on there as well.

It's safe to say it's covering 1/4 of the state, in the canyons that the signal can get through. For a few weeks after they came on the air, they were airing reports of the distant locations the AM was being heard.

That's really cool!

So, does this facility have enough AM listeners to keep that 50k on during daylight hours?

Ehh... probably not. At one time though, such a station probably would've commanded listeners from Phoenix down to Nogales, and back up to Tucson.

There's also a nighttime signal issue too. In Montgomery Alabama, as a bad example, the AM band is unlistenable after dark. I did a check not too long, while visiting there and discovered it. Their AM stations broadcast with 1000 Watts to less than that at night.​

Dan <><

Yikes! What exactly was your conditions like (were you inside, possibly close to a noise source?) At the very least, WRBZ, WMGY, and WXVI should've came in decent. This does prove that today's AM band is a complete mess compared to previously.

We didn't get an FM radio at home until the late 70s, or in the car until 1983.

That is about what I expected, honestly.

 

[R.D.P.]

Yikes! What exactly was your conditions like (were you inside, possibly close to a noise source?) At the very least, WRBZ, WMGY, and WXVI should've came in decent. This does prove that today's AM band is a complete mess compared to previously.

I was inside a Chevy Vehicle, when I checked it. Two of those stations could be heard but also included noise issues. (WMGY and WXVI) The other one couldn't be heard at all. (WRBZ) The check happened in the parking lot of a Wal-Mart store, just a few feet down from the old Montgomery Mall.

Dan <><​

 

[SomeRadioGuy]

There's also a nighttime signal issue too. In Montgomery Alabama, as a bad example, the AM band is unlistenable after dark. I did a check not too long, while visiting there and discovered it. Their AM stations broadcast with 1000 Watts to less than that at night.​

Dan <><

Yikes! What exactly was your conditions like (were you inside, possibly close to a noise source?) At the very least, WRBZ, WMGY, and WXVI should've came in decent. This does prove that today's AM band is a complete mess compared to previously.

I lived in montgomery back in 2004.. and the only AMs i remember being listenable at night were WMGY and WXVI.

1170 was still 1kw into 6 towers back then, and their night pattern looked like lop sided saggy boobs

WRBZ, then WAPZ.. signed off at sunset and wasnt on most sundays

 

[Mikey Radio]

their night pattern looked like lop sided saggy boobs

Was this done on purpose??

 

[SomeRadioGuy]

Was this done on purpose??

By the station or my description? The later, yes.. cuse thats what it seriously looked like

I think as for the station.. thats just what they ended up with.. i wish we could go back and find an old coverage map