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FM Translators killing AM stations

I agree completely that the translator solution is good for now. But what about 10 years from now? When FM came along, nobody had receivers. It wasn't until the programming was there that people bought them, and a simple mandate from the gov't that every car have an AM/FM radio sure helped too.

We will need to do something to mitigate the crowding in the FM band. Another LPFM window sure won't help. Something needs to be done, and WiFi/Broadband isn't the solution since you're paying per listener. It costs the same whether I have 10 people or 10 million people listening to a transmitter. Not true with broadband. Do the math on the bandwidth of 700,000 people listening to a 32kbpz stream during drive time on their smartphones (if say, 1010 WINS was completely on broadband and not AM). Plus add in everyone's phone calls.
 
This comes up every now and then: FM has never been mandated in radios. The most the FCC did, was to require it to air separate programming from its AM counterpart
 
I keep reading comments alluding to FM overcrowding, but not much discussion on how that is defined. Where is this occurring and what is the symptom that is being discussed? I can't point to very many cases where overcrowding seems to be having a negative impact on overall listenership.
 
Kmagrill said:
I keep reading comments alluding to FM overcrowding, but not much discussion on how that is defined. Where is this occurring and what is the symptom that is being discussed?

The way you have phrased the question makes it clear that "overcrowding" is an ill chosen word to describe what is usually meant. The implication of "overcrowding" is that the spectrum is like an airliner where every seat is filled, and the guy who feels he must get on this particular flight thinks of the plane as "overcrowded" when what he is really reporting is that the airplane is full.

The FCC has created rules defining how close together FM stations can be... in actual calculated RF signal delivered up against the RF signal of another adjacent station on the same frequency, or one or two frequencies on either side ... or in arbitrary mileage separations between stations in LPFM for example.

We use the term overcrowded when we are complaining that we cannot find a vacant spot to put one more station in a market where we want to be if in the business.... or in the case of radio listeners, the complaint is that surely someone would put in a station doing what I want to hear, if the spectrum was not already full (overcrowded).

In theory, the system should work just fine if the FCC rules have been followed. There are two reasons why it doesn't always work just fine: (1) poor receivers that cannot pick one signal clearly when two are on the verge of interfering. (2) FM actually turns out to be a bit more squirrely than Mr. Armstrong claimed when he invented the concept and wrote the text book.
 
Where I live, which is between two medium sized cities 50 miles apart, is the definitive in overcrowded dial short of NYC, LA, and other such cities. And often as not, the signal I want to listen to has a blowtorch next door or second adjacent.
 
Stations are only protected out to the 60(or 54, in Class B territory)dbu contour. Anything beyond that is "bonus" coverage and only comes in because nothing is blocking it.
 
Goat Rodeo Cowboy said:
Kmagrill said:
I keep reading comments alluding to FM overcrowding, but not much discussion on how that is defined. Where is this occurring and what is the symptom that is being discussed?

The way you have phrased the question makes it clear that "overcrowding" is an ill chosen word to describe what is usually meant. The implication of "overcrowding" is that the spectrum is like an airliner where every seat is filled, and the guy who feels he must get on this particular flight thinks of the plane as "overcrowded" when what he is really reporting is that the airplane is full.

The FCC has created rules defining how close together FM stations can be... in actual calculated RF signal delivered up against the RF signal of another adjacent station on the same frequency, or one or two frequencies on either side ... or in arbitrary mileage separations between stations in LPFM for example.

We use the term overcrowded when we are complaining that we cannot find a vacant spot to put one more station in a market where we want to be if in the business.... or in the case of radio listeners, the complaint is that surely someone would put in a station doing what I want to hear, if the spectrum was not already full (overcrowded).

In theory, the system should work just fine if the FCC rules have been followed. There are two reasons why it doesn't always work just fine: (1) poor receivers that cannot pick one signal clearly when two are on the verge of interfering. (2) FM actually turns out to be a bit more squirrely than Mr. Armstrong claimed when he invented the concept and wrote the text book.

Cowboy, you must live in the middle of nowhere out in Zone II (which from your username makes sense)! Overcrowding is not being able to move an antenna site one mile. Overcrowding is having short-spaced stations in every direction, an analog station on almost every channel with half of them running IBOC, most stations having Longley-Rice contours that exceed the FCC predicted contours due to flat terrain, several stations with grandfathered facilities over class limits, omni-directional stations that aren't really omnidirectional, directional stations that haven't checked their pattern nulls in 40 years, and a world of crazed translator operators who think they have a God-given right to as many repeaters and as much spectrum as they can con the FCC into giving them. Mix in some tropo-ducting and you have a recipe for something that approaches unusable. Ok, I've pushed it a bit, but you get the idea; the airliner not only has every seat filled, but so are the laps, the aisles, and the restrooms!
 
local oscillator said:
Goat Rodeo Cowboy said:
Kmagrill said:
I keep reading comments alluding to FM overcrowding, but not much discussion on how that is defined. Where is this occurring and what is the symptom that is being discussed?

The way you have phrased the question makes it clear that "overcrowding" is an ill chosen word to describe what is usually meant. The implication of "overcrowding" is that the spectrum is like an airliner where every seat is filled, and the guy who feels he must get on this particular flight thinks of the plane as "overcrowded" when what he is really reporting is that the airplane is full.

Cowboy, you must live in the middle of nowhere out in Zone II (which from your username makes sense)! Overcrowding is not being able to move an antenna site one mile. Overcrowding is having short-spaced stations in every direction, an analog station on almost every channel with half of them running IBOC, most stations having Longley-Rice contours that exceed the FCC predicted contours due to flat terrain, several stations with grandfathered facilities over class limits, omni-directional stations that aren't really omnidirectional, directional stations that haven't checked their pattern nulls in 40 years, and a world of crazed translator operators who think they have a God-given right to as many repeaters and as much spectrum as they can con the FCC into giving them. Mix in some tropo-ducting and you have a recipe for something that approaches unusable. Ok, I've pushed it a bit, but you get the idea; the airliner not only has every seat filled, but so are the laps, the aisles, and the restrooms!

That is an excellent response... addressing some frustrations that exist in how FM stations are allocated, granted, modified. My post was (poorly?) designed to do several things. (1) suggest to readers and contributors to the thread, that the view of people in the business or wanting to be in the business runs one direction, and views of people who are fans and listeners run in another direction. It would be good in participants here made it clear what is their motivation. (2) Participants in this discussion would help this discussion if they explained who would benefit if certain legal change, policy changes were implemented... as in "the indjustry would benefit" or ....as in "the listener would beneit" ...as in "our culture, our country, our community would benefit." (3) We need to choose words that bring improved understanding, clarity and integrity to the thread.

A little self disclosure: I have lived in multiple states and do not have an overwhelming attachment or loyalty to my current address to argue for a change in the system that would benefit my neighborhood if it resulted in a system that put other communities at a great disadvantage. I am a "has been"... a person who once had a legitimate place in the industry in multiple communities, multiple states. In recent years I made an significant effort to return to the industry in the role of a licensee but didn't get the job done. The probabilities are quite low that I will continue that effort.

Here is where I am coming from in this thread: Translators per se are NOT THE PROBLEM. Poor engineering rules and definitions leave too many opportunities to BEND the rules. Poor definitions (by the FCC) of what are legitimate reasons for the existence of all classes of stations are a bigger problem than the existence of translators, or the existence of an imbalance of AM locations and power levels, or the existence of tunneling and other realities of FM propagation that was not well understood when the FCC rules were developed.

I hope from this discussion we can see some fixes that we could support to make the future of broadcasting better.
 
It seems to me that this particular discussion boils down to a political point of view more than a technical one. If one is of a mind set that the spectrum is overcrowded and poorly managed, then translators just add to that condition. If you think the airwaves are currently okay, then translators are probably fine. As general discussions about so called overcrowding seem to be beyond the scope of this topic, strictly referring to translators and "overcrowding", I don't think they really can do that under the current rules, except to an LPFM. Any translator causing interference to any full service station, even outside of the station's protected contour can be forced off the air, as we witnessed recently in Detroit. That pretty much makes it impossible for a translator to cause meaningful interference to anyone, anywhere. It is a short step from that position to state that they cannot contribute to overcrowding since they can be displaced or removed at any time that they are demonstrated to be a problem. One bona-fide listener complaint is all it takes.
 
This thread pulls up the perennial controversy: how much interference protection should a station get?

- How weak of a signal should we protect?

Your car radio can probably deliver good-quality audio from a signal of 40dBu or less. Your $20 clock radio probably requires something on the order of 60dBu, and that $5 thing you carry when you go jogging may require 70dBu. It also varies from listener to listener: (and even from format to format) I've listened to some pretty noisy signals on the order of 10-20dBu if I liked the format.

Protect a station to its 40dBu contour, and listeners with cheap receivers are going to hear a blank spot on the dial & wonder, "why can't someone build a station carrying {my favorite music} on this blank spot?" Protect it only to the 70dBu, and listeners with good receivers are going to ask "why is that %^(*&%* new {other guy's favorite format} station interfering with my favorite station?"

- How cheap of a receiver should we protect?

Semi-related. Good modern receivers, like your car radio, will have no problems separating stations 0.4MHz apart on the dial. (HD radios can often separate stations 0.2MHz apart) Your cheap hang-around-your-neck jogging radio may require 0.8MHz. Again, some listeners may tolerate a bit of adjacent-channel interference if they like the format -- others won't.

Protect a station to 0.8MHz, and listeners with *good* radios hear blank spots on their dial. (and wonder why there can't be a station there) Protect it to 0.4MHz, and listeners with cheap radios wonder why something is interfering with their favorite station.

_________________________________________________

It is interesting to note that in the initial NPRM that resulted in the current framework of FM rules proposed protection to as low as the 38.5dBu contour. A 100kw station would have been protected from interference to a distance of 100 miles!
 
w9wi said:
It is interesting to note that in the initial NPRM that resulted in the current framework of FM rules proposed protection to as low as the 38.5dBu contour. A 100kw station would have been protected from interference to a distance of 100 miles!

Out here in the west, a 100 kW station on top of a mountain can easily get out 100 miles or more. In my car while driving in the SE part of the Phoenix area, I can easily hear several Tucson stations (100 miles), and one from Flagstaff (140 miles) - not to mention several others in the 70-90 mile range that are Phoenix rimshots. The Flagstaff station is noisy but listenable, and it disappears if South Mountain is between it and me, but it is audible in a good portion of the metro. I've also heard the South Mountain 100 kW stations in Tucson.

I would think the same is true in the midwest if the station is on a tall-enough tower.
 
KeithE4 said:
w9wi said:
It is interesting to note that in the initial NPRM that resulted in the current framework of FM rules proposed protection to as low as the 38.5dBu contour. A 100kw station would have been protected from interference to a distance of 100 miles!

Out here in the west, a 100 kW station on top of a mountain can easily get out 100 miles or more. In my car while driving in the SE part of the Phoenix area, I can easily hear several Tucson stations (100 miles), and one from Flagstaff (140 miles) - not to mention several others in the 70-90 mile range that are Phoenix rimshots. The Flagstaff station is noisy but listenable, and it disappears if South Mountain is between it and me, but it is audible in a good portion of the metro. I've also heard the South Mountain 100 kW stations in Tucson.

I would think the same is true in the midwest if the station is on a tall-enough tower.
Here in Indiana (a flat landscape for the most part), we have class B's that range from about 50KW at 500' to about 12.5KW at 1000'. Actually, there is one tower that sports both of those facilities. As a frequent dial spinner, I can't say that the added height/lower power causes the taller station to be listenable any farther. Even the two grandfathered B+ stations (37KW at roughly 1050' and 58KW at about 800') don't have a night and day advantage over the standard B's. At least in this part of the midwest, I'd have to opine that we have nothing remotely like the routine 100 mile coverage you enjoy in Arizona. And with as packed as our dial has become, that's probably a good thing. I guess a simple "is the dial too crowded" question could be this : How many frequencies can I run a legal Part 15 FM transmitter on and hear it at least 100'? I'm running low on options myself.
 
BobOnTheJob said:
Here in Indiana (a flat landscape for the most part)...

Not the part of Indiana I'm from. ;D

There's probably a good reason why Bloomington has 5 FM translators licensed to it. That hilly country is brutal on radio reception, at least from what I remember from decades ago.

...we have class B's that range from about 50KW at 500' to about 12.5KW at 1000'. Actually, there is one tower that sports both of those facilities. As a frequent dial spinner, I can't say that the added height/lower power causes the taller station to be listenable any farther. Even the two grandfathered B+ stations (37KW at roughly 1050' and 58KW at about 800') don't have a night and day advantage over the standard B's. At least in this part of the midwest, I'd have to opine that we have nothing remotely like the routine 100 mile coverage you enjoy in Arizona. And with as packed as our dial has become, that's probably a good thing. I guess a simple "is the dial too crowded" question could be this : How many frequencies can I run a legal Part 15 FM transmitter on and hear it at least 100'? I'm running low on options myself.

It's been many years since I traveled from Chicago to Bloomington, but I do remember WTTS 92.3 being audible on I-65 near Rensselaer - about 125 miles from the Trafalgar tower. The other Indy-area stations would fade just north of Lafayette.
 
Most of the commercial stations in Houston,TX are 100kw on 2000' towers and can be heard on car radios 100 miles out at most times. KTHT whose tower is in Cleveland,TX shows up in the Lake Charles ratings consistently even from 117 air miles away.
 
Good points, all.

Here's my disclosure: I am a longtime owner of an FM in the Zone I portion of the Midwest. I am also a big fan/listener of Radio; in addition to my station, I listen to several of my competitors' stations for (gasp) enjoyment. I do listen most often to my car's Chrysler/Boston Acoustics Radio, but I also listen at home to a Boston Acoustics Receptor (analog version) Radio and a Bose WaveRadio. They all have reasonable selectivity and sensitivity. Based on where I live and how I listen, I feel the band is overcrowded. In my area, stations interfering with each other are far more common than "silent" channels. I realize that your results may vary. In my opinion, the four biggest causes of FM clutter are: 1) IBOC, 2) grandfathered super-power, 3) non-fill-in use of translators, and 4) temperature inversions/ducting. The first three are self inflicted. Again, I understand that your experiences and opinions may vary.

I'm quite familiar with the translator shutdown in Detroit. Six months of interference, several FCC filings, an on-air/online PR campaign, and thousands in legal fees are what it took WIOT/Toledo to get rid of the translator. Even though your case may be just and you eventually prevail, it's not as easy as it sounds!
 
KeithE4 said:
BobOnTheJob said:
Here in Indiana (a flat landscape for the most part)...

Not the part of Indiana I'm from. ;D

There's probably a good reason why Bloomington has 5 FM translators licensed to it. That hilly country is brutal on radio reception, at least from what I remember from decades ago.

...we have class B's that range from about 50KW at 500' to about 12.5KW at 1000'. Actually, there is one tower that sports both of those facilities. As a frequent dial spinner, I can't say that the added height/lower power causes the taller station to be listenable any farther. Even the two grandfathered B+ stations (37KW at roughly 1050' and 58KW at about 800') don't have a night and day advantage over the standard B's. At least in this part of the midwest, I'd have to opine that we have nothing remotely like the routine 100 mile coverage you enjoy in Arizona. And with as packed as our dial has become, that's probably a good thing. I guess a simple "is the dial too crowded" question could be this : How many frequencies can I run a legal Part 15 FM transmitter on and hear it at least 100'? I'm running low on options myself.

It's been many years since I traveled from Chicago to Bloomington, but I do remember WTTS 92.3 being audible on I-65 near Rensselaer - about 125 miles from the Trafalgar tower. The other Indy-area stations would fade just north of Lafayette.
Getting WTTS at Rensselaer would be a neat trick...it's just outside of the 54dbu protected contour of 50KW WPWX in Hammond,IN.
 
BobOnTheJob said:
Getting WTTS at Rensselaer would be a neat trick...it's just outside of the 54dbu protected contour of 50KW WPWX in Hammond,IN.

This was back in the '70s and '80s. I don't think then-WYCA was running much power in those days. It would disappear before some of the Sears Tower-based stations did.
 
If you remain at the top of your license class, increasing tower height while decreasing power, shouldn't change the limits of the station contours, just improve the usable signal within those contours. It's generally better to run 20KW from a mountaintop than 100kw from your AM tower.
 
When figuring radio horizon over average terrain I used a simple formula that took the square root of the overall height (in feet) and doubled that number to suggest the horizon in miles.

Example: a 144 foot tower has a square root of 12 feet and multiplying that X2 ='s 24 (miles) that is very close.

Now, a thousand foot tower has a square root of ~31 X 2 is 62 (miles) which is very close to what can be expected over water.

Terrain is the variable....
 
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