And in other news...

[dbdigital]

Here's an interesting twist on the LPFM issue (and right on the heels of the Goldfield waiver).

Because of the outcry from the townspeople of Kilgore, TX over the sale of KTPB-FM to Educational Media Foundation, the FCC is waiving the rule for an open window and allowing Kilgore's citizens to apply for an LPFM station within 90 days. The Commission even found an open frequency and transmitter location for them.

Apparently, when the sale of a station is objected to by enough of the public, the FCC will listen.

http://hraunfoss.fcc.gov/edocs_public/attachmatch/DA-07-450A1.txt

db

 

[jcolletta275]

I heard about this... good news! It's not quite the outcome I imagine most Kilgore residents would've wanted, and according to the article I read (I believe it was on AllAccess) they don't have a potential owner to fill the new frequency yet, but it's better than nothing at all.

 

[dbdigital]

I heard about this... good news! It's not quite the outcome I imagine most Kilgore residents would've wanted, and according to the article I read (I believe it was on AllAccess) they don't have a potential owner to fill the new frequency yet, but it's better than nothing at all.

Right. Now the good people of Kilgore are going to have to scramble to find a non-profit group who would both qualify and be willing to apply for an LPFM license. Then there's the cost of building the station and finding volunteers to run it.

But obviously, this waiver is a response to public outcry and the "spanking" the FCC is getting from Congress over the issue of media ownership and lack of localism.

db

 

[Chuck]

Speaking as somebody who has a Kilgore mailing address, the LPFM "bone" thrown out by the FCC isn't as generous as it would appear. The station that was sold was 60,000 watts and had very good coverage.

The LPFM site specified by the FCC is about 8.5 miles from the center of Kilgore on the west-northwest side. It isn't even in the same county. Very few people live west of the downtown area. It is mostly an industrial district, or just open land, so you would be broadcasting to very few residents. It is very questionable that the signal would be receivable on most ordinary radios in the city's residential areas. It would probably be OK in a car radio as you drive around town. Depending on co-channel interference conditions, most LPFM’s have a reliable car radio signal for 10 miles. With no interference, they can go farther. At the proposed transmitter site, you can receive a signal from a co-channel station located in Dallas, on an ordinary car radio. It is weak, but there will be a problem. Further, the proposed site is about 22 miles from downtown Longview, and about 25-30 miles from Tyler. Most of the people who protested the sale were residents of Tyler or Longview. The LPFM will not do them much good.

What will happen, remains to be seen.

 

[dbdigital]

Speaking as somebody who has a Kilgore mailing address, the LPFM "bone" thrown out by the FCC isn't as generous as it would appear. The station that was sold was 60,000 watts and had very good coverage.

The LPFM site specified by the FCC is about 8.5 miles from the center of Kilgore on the west-northwest side. It isn't even in the same county. Very few people live west of the downtown area. It is mostly an industrial district, or just open land, so you would be broadcasting to very few residents. It is very questionable that the signal would be receivable on most ordinary radios in the city's residential areas. It would probably be OK in a car radio as you drive around town. Depending on co-channel interference conditions, most LPFM’s have a reliable car radio signal for 10 miles. With no interference, they can go farther. At the proposed transmitter site, you can receive a signal from a co-channel station located in Dallas, on an ordinary car radio. It is weak, but there will be a problem. Further, the proposed site is about 22 miles from downtown Longview, and about 25-30 miles from Tyler. Most of the people who protested the sale were residents of Tyler or Longview. The LPFM will not do them much good.

What will happen, remains to be seen.

Sounds as if internet streaming your LPFM's signal will be the main way that the station will reach the town's folk (and perhaps cable FM).

Are the people of Kilgore going to proceed with the filing? Have they found or will they create a non-profit organization to operate the station?

db

 

[Chuck]

Are the people of Kilgore going to proceed with the filing? Have they found or will they create a non-profit organization to operate the station?

db

That's a really good question. The people who complained about the KTPB sale formed a nonprofit called SOAR (Save Our Arts Radio). They do not seem interested, since it will not serve Tyler. Most of their supporters live in that city. So far, the college has not been interested either, but I'm working on them. I am GM of the "other" LPFM in the area, and have a very good relationship with the college and (hopefully) the community.

Right now it is all a mystery as to how it will fall out. Since the new station has a very poor probability of succeeding due to its location, it is possible that nobody will bother to file. I'd hate to see that happen.

 

[Black_Shire]

Are the people of Kilgore going to proceed with the filing? Have they found or will they create a non-profit organization to operate the station?

db

That's a really good question. The people who complained about the KTPB sale formed a nonprofit called SOAR (Save Our Arts Radio). They do not seem interested, since it will not serve Tyler. Most of their supporters live in that city. So far, the college has not been interested either, but I'm working on them. I am GM of the "other" LPFM in the area, and have a very good relationship with the college and (hopefully) the community.

Right now it is all a mystery as to how it will fall out. Since the new station has a very poor probability of succeeding due to its location, it is possible that nobody will bother to file. I'd hate to see that happen.

Depending on the population and geographical extent of Kilgore (both are quite small), there is another interesting possibility: a Part 15 Long Wave community radio station. These 160 kHz - 190 kHz stations are usually operated as slow CW (Morse Code) or digital mode beacons (called "LowFER" beacons), although a LowFER operator in Sunnyvale, California broadcasts music in AM mode over his LowFER station with good ground wave propagation. LowFER beacons may operate at 1 watt output power into a 15 meter antenna, with all modes (CW, AM, SSB, etc.) allowed.

Coby Electronics makes inexpensive AM/FM/Short Wave/Long Wave receivers that could be distributed to the Kilgore residents. Being a small isolated community, the 160 kHz - 190 kHz LowFER band should be relatively free of noise.


-- Black Shire

 

[rfry]

Depending on the population and geographical extent of Kilgore (both are quite small), there is another interesting possibility: a Part 15 Long Wave community radio station.... LowFER beacons may operate at 1 watt output power into a 15 meter antenna, with all modes (CW, AM, SSB, etc.) allowed.

That's an interesting thought. Some quick calculations show that a 15-meter vertical monopole with 100 mm OD used on 170 kHz with 1 watt of available tx power would produce a field at 1 km that would be roughly the same as from a 3-meter, 12.5 mm OD radiator on 1.7 MHz with 75 mW of available tx output power (a Part 15.219 AM setup).

The reduced radiation efficiency of the 170 kHz antenna system just about offsets the higher power tx used with it (10 kHz audio bandwidth for both systems).

Propagation losses are lower for the 170 kHz system, but then good receiver sensitivity (including its antenna) is harder to achieve on 170 kHz, compared to standard AM broadcast receivers -- so these two factors also will tend to equalize the performance of these two systems.

A Part 15.219 AM medium wave system could be preferable, given the general lack of "broadcast" receivers for 170 kHz.
//

 

[Chuck]

A Part 15.219 AM medium wave system could be preferable, given the general lack of "broadcast" receivers for 170 kHz.
//

Since the format of the old station (KTPB) was classical and jazz, I somehow doubt that AM would be a suitable replacement.

 

[Black_Shire]

<That's an interesting thought. Some quick calculations show that a 15-meter vertical monopole with 100 mm OD used on 170 kHz with 1 watt of available tx power would produce a field at 1 km that would be roughly the same as from a 3-meter, 12.5 mm OD radiator on 1.7 MHz with 75 mW of available tx output power (a Part 15.219 AM setup).>

There's your lack of real-world Part 15 experience showing again... In the field of LowFER beacons, the 15 meter vertical is used in the same way as the isotropic radiator--as a theoretical "yardstick" antenna (and the least efficient one) against which other LowFER antennas are compared. The 15 meter vertical is a nice "straw man" LowFER antenna for your calculations, but virtually all LowFER beacon operators use top-loaded Marconi "Tee" wire antennas to ensure better RF current distribution in the vertical radiating element (and thus more radiation).

<A Part 15.219 AM medium wave system could be preferable, given the general lack of "broadcast" receivers for 170 kHz.>

The Coby CX-CB12 AM/FM/Short Wave/Long Wave receivers are readily available (I have one myself) here:
http://www.cobyusa.com/_en/prod_item.php?item=CXCB12&pcat=portaudio&pscat=radio&pscat2=#

 

[Black_Shire]

A Part 15.219 AM medium wave system could be preferable, given the general lack of "broadcast" receivers for 170 kHz.
//

Since the format of the old station (KTPB) was classical and jazz, I somehow doubt that AM would be a suitable replacement.

It's suitable if the only alternative is dead air on the local airwaves... Actually, AM sounds quite good with proper audio processing. Just this morning I listened to "Big Band Jump" hosted by Don Kennedy on KFAR 660 AM, and the many jazz pieces he played sounded crisp and sweet over this local AM station.

 

[rfry]

In the field of LowFER beacons, the 15 meter vertical is used in the same way as the isotropic radiator--as a theoretical "yardstick" antenna (and the least efficient one) against which other LowFER antennas are compared. The 15 meter vertical is a nice "straw man" LowFER antenna for your calculations, but virtually all LowFER beacon operators use top-loaded Marconi "Tee" wire antennas to ensure better RF current distribution in the vertical radiating element (and thus more radiation).

Sorry, but evidence is that you have been mis-informed.

Note the applicable text for this "LowFER" application in Part 15.217 below, taken from the FCC web site a few minutes ago.

Nothing there even implies that the 15-meter length for the radiator is to be considered the same as an isotropic radiator, and/or that "Tee" antennas may be used.

But no doubt all of us are open to accept any published FCC regulations and/or policies proving that what you have posted is accurate. If you have it, would mind sharing it with us?
//
__________

[Code of Federal Regulations]
[Title 47, Volume 1]
[Revised as of October 1, 2001]
From the U.S. Government Printing Office via GPO Access
[CITE: 47CFR15.217]

[Page 725]

TITLE 47--TELECOMMUNICATION

CHAPTER I--FEDERAL COMMUNICATIONS COMMISSION

PART 15--RADIO FREQUENCY DEVICES--Table of Contents

Subpart C--Intentional Radiators

Sec. 15.217 Operation in the band 160-190 kHz.

(a) The total input power to the final radio frequency stage
(exclusive of filament or heater power) shall not exceed one watt.
(b) The total length of the transmission line, antenna, and ground
lead (if used) shall not exceed 15 meters.
(c) All emissions below 160 kHz or above 190 kHz shall be attenuated
at least 20 dB below the level of the unmodulated carrier. Determination
of compliance with the 20 dB attenuation specification may be based on
measurements at the intentional radiator's antenna output terminal
unless the intentional radiator uses a permanently attached antenna, in
which case compliance shall be demonstrated by measuring the radiated
emissions.

 

[Chuck]

It's suitable if the only alternative is dead air on the local airwaves... Actually, AM sounds quite good with proper audio processing. Just this morning I listened to "Big Band Jump" hosted by Don Kennedy on KFAR 660 AM, and the many jazz pieces he played sounded crisp and sweet over this local AM station.

It would be easier and/or simpler if the folks who wanted to listen to classical music just subscribed to XM or Sirius. The likelihood of them adopting Long Wave AM radios is somewhere between slim and none. You'd have a better chance of getting an FMExtra or HD-2 channel on a lease basis from someone who had decent coverage in the area. Even that would be tough to make self-sustaining

Don't get me wrong. I'm a big fan of LOCAL radio. I'm GM of a successful LPFM community station. I am also a realist. The LPFM option suggested by the FCC is a lame replacement for what was lost, although it may be the best bet. Due to its location, it is going to be very difficult to make it fly, even if it manages to get on the air.

 

[Black_Shire]

I'll repeat what I said before in very simple terms so that you can understand it: LowFER beacon operators use the 15 meter vertical as a reference antenna (as the isotropic antenna is used elsewhere) because it is the least efficient one allowed by the Part 15 rules. No one uses it in practice, except perhaps as a temporary replacement for a permanent LowFER antenna that is damaged by ice or storms.

Virtually all LowFER beacon operators use some form of capacitive top-loading to increase the RF currents in the upper part of the antenna. They "budget" their allowed length (15 meters) between the vertical radiator height and the capacitive "top-hat" radius (or half-span in the case of Marconi "Tee" antennas, the most commonly-used antennas for LowFER beacons). Depending on the available antenna supports at each site and the beacon operators' monetary budgets, some LowFER antennas are short with wide "top-hats" while others are tall with small "top hats," but the total height + "top hat" radius = 15 meters. (And yes, the LowFER beacon operators *do* interpret the 15 meter length as being the vertical radiator height + the "top hat" radius instead of the "top hat" diameter or total span, but that's the way they have always built them, and the FCC either agrees with them or simply doesn't care. LowFER beacon operators also use ground radial wire systems with their 15 meter antennas.)

In the field of LowFER beacons, the 15 meter vertical is used in the same way as the isotropic radiator--as a theoretical "yardstick" antenna (and the least efficient one) against which other LowFER antennas are compared. The 15 meter vertical is a nice "straw man" LowFER antenna for your calculations, but virtually all LowFER beacon operators use top-loaded Marconi "Tee" wire antennas to ensure better RF current distribution in the vertical radiating element (and thus more radiation).

Sorry, but evidence is that you have been mis-informed.

Note the applicable text for this "LowFER" application in Part 15.217 below, taken from the FCC web site a few minutes ago.

Nothing there even implies that the 15-meter length for the radiator is to be considered the same as an isotropic radiator, and/or that "Tee" antennas may be used.

But no doubt all of us are open to accept any published FCC regulations and/or policies proving that what you have posted is accurate. If you have it, would mind sharing it with us?
//
__________

[Code of Federal Regulations]
[Title 47, Volume 1]
[Revised as of October 1, 2001]
From the U.S. Government Printing Office via GPO Access
[CITE: 47CFR15.217]

[Page 725]

TITLE 47--TELECOMMUNICATION

CHAPTER I--FEDERAL COMMUNICATIONS COMMISSION

PART 15--RADIO FREQUENCY DEVICES--Table of Contents

Subpart C--Intentional Radiators

Sec. 15.217 Operation in the band 160-190 kHz.

(a) The total input power to the final radio frequency stage
(exclusive of filament or heater power) shall not exceed one watt.
(b) The total length of the transmission line, antenna, and ground
lead (if used) shall not exceed 15 meters.
(c) All emissions below 160 kHz or above 190 kHz shall be attenuated
at least 20 dB below the level of the unmodulated carrier. Determination
of compliance with the 20 dB attenuation specification may be based on
measurements at the intentional radiator's antenna output terminal
unless the intentional radiator uses a permanently attached antenna, in
which case compliance shall be demonstrated by measuring the radiated
emissions.

 

[Neil E.]

BlackShire,

I have never had the opportunity to experiment with Lowfer operations. Based on your experience, give any "legal" antenna that you choose, what range can I expect to achieve with 10 kHz. bandwidth AM? Is it comparable to or does it exceed the range obtained with part 15 broadcast band operations?

Thanks,

Neil

 

[dbdigital]

Just taking a short detour here, but since we were originally talking about a town losing it's local NCE FM station, I thought some of you might find this website of interest: http://savelocalfm.org/

I'm not sure if this is just a website or a movement but the focus here is on move-ins, the new FCC rules on changing FM allotments and how this is affecting community FM. Worth looking at.

Didn't mean to interrupt your discussion on part 15 LowFER broadcasting.

db

 

[rfry]

Virtually all LowFER beacon operators use some form of capacitive top-loading to increase the RF currents in the upper part of the antenna. They "budget" their allowed length (15 meters) between the vertical radiator height and the capacitive "top-hat" radius (or half-span in the case of Marconi "Tee" antennas, the most commonly-used antennas for LowFER beacons). Depending on the available antenna supports at each site and the beacon operators' monetary budgets, some LowFER antennas are short with wide "top-hats" while others are tall with small "top hats," but the total height + "top hat" radius = 15 meters.

This all sounds good at first, but what isn't being recognized is that while such a Tee antenna with a total linear length of 15 meters split between the vertical and horizontal sections will raise the radiation resistance of the vertical section (good), it also increases the feedpoint reactance (not good).

The increased reactance means that the coil inductance needed to achieve system resonance will rise, which means that the Q of the antenna system will be reduced (other things equal).

Maintaining sufficient r-f bandwidth for good audio fidelity is important when "broadcasting," so that means that a certain minimum Q is required, and that requires a certain minimum value of resistive loss relative to the reactance of the radiator and the operating frequency.

The link below compares the signal strengths at 1 km for two 15.217 "LowFER" systems compared to a system operating under Part 15.219, all with the same r-f bandwidth.

It is clear from this evaluation that the field at 1 km from the Tee LowFER system is the worst of the three systems shown. A deeper explanation, and detailed proof is available on request.

http://i62.photobucket.com/albums/h85/rfry-100/LoFER.gif
//

 

[Neil E.]

db,

These threads do tend to take on a life of their own, don't they?

Neil

 

[dbdigital]

db,

These threads do tend to take on a life of their own, don't they?

Neil

LOL. This is true but I enjoy it. For example, I know very little about LowFER so this discussion has actually been quite interesting (if somewhat removed from the original topic).

db

 

[Black_Shire]

Sorry about that, dbdigital! I had just brought up the Part 15 Long Wave option as a possibility in the event that Kilgore can't put together an organization to grab an LPFM CP in time. If the community can manage it (they'll have to scramble, but it can be done), an LPFM station would of course be a better option.

Just taking a short detour here, but since we were originally talking about a town losing it's local NCE FM station, I thought some of you might find this website of interest: http://savelocalfm.org/

I'm not sure if this is just a website or a movement but the focus here is on move-ins, the new FCC rules on changing FM allotments and how this is affecting community FM. Worth looking at.

Didn't mean to interrupt your discussion on part 15 LowFER broadcasting.

db