FM radio puzzler
 

I'm in Mountain View, CA and trying to find station KSFH-FM, which is an
FCC-licensed Class "D" station. It is owner by a local school, and when I call
them they say they're on the air with programming. I am 1 mile from the campus
and can SEE the antenna. I tune to every channel from 88.1 to 107.9 MHz.
Nothing, except, of course, the other stations normally heard. I also try
holding my antenna sideway, vertical, every which way.
I call the FCC office in San Francisco and they say yes they're a legal
station, and they should reach at least 3 miles, so try again. Again nothing.
What is going on?

I think you should drive right up to the station, tune in on your car
radio, then drive home and see where and why the signal disappears. I
suspect your radio is being captured by a strong adjacent channel
transmitter.

Norm Lehfeldt

(Radioman390) wrotf:

I'm in Mountain View, CA and trying to find station KSFH-FM, which is an
FCC-licensed Class "D" station. It is owner by a local school, and when I call
them they say they're on the air with programming. I am 1 mile from the campus
and can SEE the antenna. I tune to every channel from 88.1 to 107.9 MHz.
Nothing, except, of course, the other stations normally heard. I also try
holding my antenna sideway, vertical, every which way.
I call the FCC office in San Francisco and they say yes they're a legal
station, and they should reach at least 3 miles, so try again. Again nothing.
What is going on?

Try URL:
http://www.radio-locator.com/cgi-bin/home

For Station Call Sign -- Type in KSFH

Sez they are at 87.9 MHz

KSFH-FM 87.9 MHz
Saint Francis High School
Mountain View, California
"Music Revolution"
Station Status Licensed Class D Non-Commercial FM Station
Area of Coverage View Coverage Map
Effective Radiated Power 10 Watts
Height above Avg. Terrain -75 meters (-245 feet)
Height above Ground Level 27 meters (89 feet)
Height above Sea Level 74 meters (243 feet)
Antenna Pattern Non-Directional
Transmitter Location 37° 22' 08" N, 122° 05' 02" W
License Granted October 09 2001
License Expires December 01 2005
Last FCC Update October 09 2001

Perhaps the map will help

--
Keyboard In The Wilderness


"Radioman390" wrote in message
...
I'm in Mountain View, CA and trying to find station KSFH-FM, which is an
FCC-licensed Class "D" station. It is owner by a local school, and when I
call
them they say they're on the air with programming. I am 1 mile from the
campus
and can SEE the antenna. I tune to every channel from 88.1 to 107.9 MHz.
Nothing, except, of course, the other stations normally heard. I also try
holding my antenna sideway, vertical, every which way.
I call the FCC office in San Francisco and they say yes they're a legal
station, and they should reach at least 3 miles, so try again. Again
nothing.
What is going on?

Also note the unusual frequency which is expalined at URL:
http://www.nationmaster.com/encyclopedia/FM-radio

Sez

FM radio channel assignments in the US
In the United States, frequency-modulated broadcasting stations operate in a
frequency band extending from 87.8 MHz to 108.0 MHz, for a total of 20.2
MHz. It is divided into 100 channels, each 0.2 MHz wide, designated "channel
200" through "channel 300." To receive a station, an FM receiver is tuned to
the center frequency of the station's channel. The lowest channel, channel
200, extends from 87.8 MHz to 88.0 MHz; thus its center frequency is 87.9
MHz. Channel 201 has a center frequency of 88.1 MHz, and so on, up to
channel 300, which extends from 107.8 to 108.0 MHz and has a center
frequency of 107.9 MHz.

--
Keyboard to you


"Keyboard In The Wilderness" wrote in message
news:xMI7d.41051$aW5.15438@fed1read07...
Try URL:
http://www.radio-locator.com/cgi-bin/home

For Station Call Sign -- Type in KSFH

Sez they are at 87.9 MHz

KSFH-FM 87.9 MHz
Saint Francis High School
Mountain View, California
"Music Revolution"
Station Status Licensed Class D Non-Commercial FM Station
Area of Coverage View Coverage Map
Effective Radiated Power 10 Watts
Height above Avg. Terrain -75 meters (-245 feet)
Height above Ground Level 27 meters (89 feet)
Height above Sea Level 74 meters (243 feet)
Antenna Pattern Non-Directional
Transmitter Location 37° 22' 08" N, 122° 05' 02" W
License Granted October 09 2001
License Expires December 01 2005
Last FCC Update October 09 2001

Perhaps the map will help

--
Keyboard In The Wilderness


"Radioman390" wrote in message
...
I'm in Mountain View, CA and trying to find station KSFH-FM, which is an
FCC-licensed Class "D" station. It is owner by a local school, and when
I
call
them they say they're on the air with programming. I am 1 mile from the
campus
and can SEE the antenna. I tune to every channel from 88.1 to 107.9 MHz.
Nothing, except, of course, the other stations normally heard. I also
try
holding my antenna sideway, vertical, every which way.
I call the FCC office in San Francisco and they say yes they're a legal
station, and they should reach at least 3 miles, so try again. Again
nothing.
What is going on?

Well, it was a trick question, but you got it right.

There was a potential second answer (maybe more) which has to do with the
phrasing I used which said I was one mile from the campus, and could see the
antenna. Well, maybe the antenna was far away (on a mountain top) and I was
out-of-range of the signal.

But my thinking in posing the mind-twister was that I didn't know the FCC had
actually granted three licenses for 87.9 (two translators and KSHR), and only
noticed while doing a search of the FCC database.

www.fcc.gov/mb
on the left side is a box marked "shortcuts"; scroll down to "FM query", and
then click on "start shortcut"

Ah OK a trick question no less

Turn about is fair play -- (but not too tricky)

On an AM radio -- one hears a station broadcasting on the tuned
frequency -- but also another station is heard that is broadcating on an
entirely different frequency !!!

Ignoring a strong adjacent channel station -- how is this possible ???

--
Keyboard mired in the political rants here (;-)


"Radioman390" wrote in message
...
Well, it was a trick question, but you got it right.

There was a potential second answer (maybe more) which has to do with the
phrasing I used which said I was one mile from the campus, and could see
the
antenna. Well, maybe the antenna was far away (on a mountain top) and I
was
out-of-range of the signal.

But my thinking in posing the mind-twister was that I didn't know the FCC
had
actually granted three licenses for 87.9 (two translators and KSHR), and
only
noticed while doing a search of the FCC database.

www.fcc.gov/mb
on the left side is a box marked "shortcuts"; scroll down to "FM query",
and
then click on "start shortcut"

Keyboard In The Wilderness schreef:

Ah OK a trick question no less

Turn about is fair play -- (but not too tricky)

On an AM radio -- one hears a station broadcasting on the tuned
frequency -- but also another station is heard that is broadcating on an
entirely different frequency !!!

Ignoring a strong adjacent channel station -- how is this possible ???

It is called mirror frequency interference.

When you receive say 540, your local oscilator produces 540 + 450 = 990
kHz. In the mixer 540 and 990 produces 990-540 = 450 (and 540+990, this
is almost fully rjected)
But suppose there is a strong signal on 1440 that is also coming into
your mixer you will find that this also produces the IF of 450 kHz,
since 1440 - 990 = 450.
So now you will hear the 540 and 1530 station; only good radio's have
proper antenna filters to reject the 1530 signal.


BTW: do US digitally controlled receivers have 87.9 ?
ruud

But

--
Keyboard mired in the political rants here (;-)

"Radioman390" wrote in message
...
Well, it was a trick question, but you got it right.

There was a potential second answer (maybe more) which has to do with the
phrasing I used which said I was one mile from the campus, and could see
the
antenna. Well, maybe the antenna was far away (on a mountain top) and I
was
out-of-range of the signal.

But my thinking in posing the mind-twister was that I didn't know the FCC
had
actually granted three licenses for 87.9 (two translators and KSHR), and
only
noticed while doing a search of the FCC database.

www.fcc.gov/mb
on the left side is a box marked "shortcuts"; scroll down to "FM query",
and
then click on "start shortcut"

Very good -- correct
Now try the other radio puzzlers.

--
Keyboard to you


"Ruud Poeze" wrote in message
...
Keyboard In The Wilderness schreef:

Ah OK a trick question no less

Turn about is fair play -- (but not too tricky)

On an AM radio -- one hears a station broadcasting on the tuned
frequency -- but also another station is heard that is broadcating on an
entirely different frequency !!!

Ignoring a strong adjacent channel station -- how is this possible ???

It is called mirror frequency interference.

When you receive say 540, your local oscilator produces 540 + 450 = 990
kHz. In the mixer 540 and 990 produces 990-540 = 450 (and 540+990, this
is almost fully rjected)
But suppose there is a strong signal on 1440 that is also coming into
your mixer you will find that this also produces the IF of 450 kHz,
since 1440 - 990 = 450.
So now you will hear the 540 and 1530 station; only good radio's have
proper antenna filters to reject the 1530 signal.


BTW: do US digitally controlled receivers have 87.9 ?
ruud

But

--
Keyboard mired in the political rants here (;-)

"Radioman390" wrote in message
...
Well, it was a trick question, but you got it right.

There was a potential second answer (maybe more) which has to do with
the
phrasing I used which said I was one mile from the campus, and could
see
the
antenna. Well, maybe the antenna was far away (on a mountain top) and
I
was
out-of-range of the signal.

But my thinking in posing the mind-twister was that I didn't know the
FCC
had
actually granted three licenses for 87.9 (two translators and KSHR),
and
only
noticed while doing a search of the FCC database.

www.fcc.gov/mb
on the left side is a box marked "shortcuts"; scroll down to "FM
query",
and
then click on "start shortcut"

Radio man asked if some digital FM radios cover 87.9 Mhz
Yep My Phillips boombox does


--
Keyboard to you


"Radioman390" wrote in message
...
Well, it was a trick question, but you got it right.

There was a potential second answer (maybe more) which has to do with the
phrasing I used which said I was one mile from the campus, and could see
the
antenna. Well, maybe the antenna was far away (on a mountain top) and I
was
out-of-range of the signal.

But my thinking in posing the mind-twister was that I didn't know the FCC
had
actually granted three licenses for 87.9 (two translators and KSHR), and
only
noticed while doing a search of the FCC database.

www.fcc.gov/mb
on the left side is a box marked "shortcuts"; scroll down to "FM query",
and
then click on "start shortcut"

On 03 Oct 2004 01:29:58 GMT, (Radioman390) wrote:

I'm in Mountain View, CA and trying to find station KSFH-FM, which is an
FCC-licensed Class "D" station. It is owner by a local school, and when I call
them they say they're on the air with programming. I am 1 mile from the campus
and can SEE the antenna. I tune to every channel from 88.1 to 107.9 MHz.

Their website http://www.ksfh.com says they-re on 87.9 FM.
What I get on that frequency, from farther up the peninsula, doesn't
sound like what I'd expect from a high school site. It also says they
have a live internet feed, whicg should make it easy to match up what
you're hearing ion the radio, but it's offline at the moment.

From (googled KSFH):
http://www.mv-voice.com/morgue/2001/2001_11_02.radio.html
"We can broadcast from and to anywhere with a phone line," he said.
Covering 90 percent of the South Bay region, KSFH 87.9 FM currently
operates at 10 watts giving them approximately a 15-mile transmission
radius from their campus. According to their Web site, in comparison,
most major commercial radio stations operate at about 5,000 watts.


That's a couple years old, but would explain why I don't hear
it.
Nothing, except, of course, the other stations normally heard. I also try
holding my antenna sideway, vertical, every which way.
I call the FCC office in San Francisco and they say yes they're a legal
station, and they should reach at least 3 miles, so try again. Again nothing.
What is going on?

They are licensed on 87.9 Mhz with a whopping 0.013 W ERP.

Try walking over there with a walkman portable radio etc. Once you hear
them you can determine the range.

RADIOMAN 390,

Currently here in OK-Land, Cali-4-Ni-A at 0200 PDT on 87.9 MHz
there seems to be Old Time Radio Programs: Sam Spade, and Dragnet.

Can hear it 'loud & clear' on the: CC Radio Plus, Sony ICF-2010,
Grundig Satellit 800 M, and Grundig S350.

Could this be KSFH or some LPFM 'pirate' ?

NOTE: I have not heard a Station ID and the Old Time Radio
Programs are giving the original ABC-CBS-NBC Radio Network IDs
and vintage radio commercials from that era.

On their website KSFH claims:
"KSFH is also the only station licensed in the United States to
broadcast on 87.9 FM. Screaming loud audio from our Mackie
Production system amplified through an Orban 8200 Audio Processor
blankets 750 square miles of Silicon Valley."
= This would be a 27+ Miles-to-a-Side Square.

FCC estimates a 2-3 Mile Signal Pattern for KSFH:
http://www.fcc.gov/fcc-bin/FMTV-serv...=FM285006.html

St. Francis High School of Mountain View
LOCATION= http://tinyurl.com/4vqvw
1885 Miramonte Avenue
Mountain View, CA 94040

Antenna Location: I would appear that the Transmitting Antenna
is located on the School's grounds.

NOTE: Use of Channel 200 [87.9 MHz] is restricted to existing
displaced full service Class D noncommercial educational
stations. See 47 CFR 73.501. Channel 200 is not available for
use by other station classes and services.
http://www.fcc.gov/fcc-bin/fmq?list=0&facid=62118

~ RHF
..
..
= = = (Radioman390) wrote in message
= = = ...
I'm in Mountain View, CA and trying to find station KSFH-FM, which is an
FCC-licensed Class "D" station. It is owner by a local school, and when I call
them they say they're on the air with programming. I am 1 mile from the campus
and can SEE the antenna. I tune to every channel from 88.1 to 107.9 MHz.
Nothing, except, of course, the other stations normally heard. I also try
holding my antenna sideway, vertical, every which way.
I call the FCC office in San Francisco and they say yes they're a legal
station, and they should reach at least 3 miles, so try again. Again nothing.
What is going on?
..

Could someone please tell me when 87.9 became a legal frequency?

All of my references (which I admit are many years old) says the
band starts at 88.1

The encyclopedia reference given previously doesn't seem to say when
the change was made.

Thanks.

--
B. Z. Lederman Personal Opinions Only

Posting to a News group does NOT give anyone permission
to send me advertising by E-mail or put me on a mailing
list of any kind.

Please remove the "DISABLE-JUNK-EMAIL" if you have a
legitimate reason to E-mail a response to this post.

According to the FCC data base
http://gullfoss2.fcc.gov/cgi-bin/ws..../frequency.hts

There are only three stations in the United States (KSFH, WA2XNX, and
translator K200AA) licensed to operate on 87.9 MHz.
KSFH is a class D educational station in Mt View, CA.
FCC data base sez K200AA is CALVARY CHAPEL OF TWIN FALLS, INC.
WA2XNX is FEDERAL SIGNAL CORPORATION classified as EX

Because the lowest channel, channel 200, extends from 87.8 MHz to 88.0 MHz;
(thus its center frequency is 87.9 MHz)
rather than say the lower FM bandedge is 87.9 MHz, I suspect it was (is)
expedient to shorten that to 88 MHz -- but just a guess.

Note that the highest channel, channel 300, extends from 107.8 to 108.0 MHz
and has a center frequency of 107.9 MHz.

So my guess is 87.9 MHz was always a "legal frequency"
But just a guess mind you.

El Guesser

--
..



"Bart Z. Lederman" wrote in
message ...
Could someone please tell me when 87.9 became a legal frequency?

All of my references (which I admit are many years old) says the
band starts at 88.1

The encyclopedia reference given previously doesn't seem to say when
the change was made.

Thanks.

--
B. Z. Lederman Personal Opinions Only

Posting to a News group does NOT give anyone permission
to send me advertising by E-mail or put me on a mailing
list of any kind.

Please remove the "DISABLE-JUNK-EMAIL" if you have a
legitimate reason to E-mail a response to this post.

Forgot to add this URL:

http://encyclopedia.thefreedictionary.com/FM%20station

All about USA FM RADIO




"El Conjeturar" wrote in message
news:Dnf9d.1254$hj.148@fed1read07...
According to the FCC data base
http://gullfoss2.fcc.gov/cgi-bin/ws..../frequency.hts

There are only three stations in the United States (KSFH, WA2XNX, and
translator K200AA) licensed to operate on 87.9 MHz.
KSFH is a class D educational station in Mt View, CA.
FCC data base sez K200AA is CALVARY CHAPEL OF TWIN FALLS, INC.
WA2XNX is FEDERAL SIGNAL CORPORATION classified as EX

Because the lowest channel, channel 200, extends from 87.8 MHz to 88.0
MHz;
(thus its center frequency is 87.9 MHz)
rather than say the lower FM bandedge is 87.9 MHz, I suspect it was (is)
expedient to shorten that to 88 MHz -- but just a guess.

Note that the highest channel, channel 300, extends from 107.8 to 108.0
MHz
and has a center frequency of 107.9 MHz.

So my guess is 87.9 MHz was always a "legal frequency"
But just a guess mind you.

El Guesser

--
.



"Bart Z. Lederman" wrote
in
message ...
Could someone please tell me when 87.9 became a legal frequency?

All of my references (which I admit are many years old) says the
band starts at 88.1

The encyclopedia reference given previously doesn't seem to say when
the change was made.

Thanks.

--
B. Z. Lederman Personal Opinions Only

FO&A,

To Answer my own Question: "Could this be KSFH or some LPFM 'pirate' ?"

San Francisco 'pirate' FM Radio Station "Pirate Cat Radio" 87.9 MHz

"Pirate Cat Radio" WebSite: www.piratecatradio.com
http://www.piratecatradio.com/site/home.html

WHY - Pirate Radio Is Currently Legal
Thanks to George Bush for declaring the "War Against Terrorism"
and U.S. Code of Federal Regulations title 47 section 73.3542,
it is now technically legal to operate a radio transmitter with
out a formal license.
http://www.piratecatradio.com/site/legal.html

"Pirate Cat Radio" 87.9 MHz Station Info:

Pirate Cat Radio
2236 Mission Street
San Francisco, CA 94110

PCR Studio Line: 1-415-401-7393

eMail:

more than you wanted to know ~ RHF
..
..
= = = (RHF) wrote in message
= = = . com...
RADIOMAN 390,

Currently here in OK-Land, Cali-4-Ni-A at 0200 PDT on 87.9 MHz
there seems to be Old Time Radio Programs: Sam Spade, and Dragnet.

Can hear it 'loud & clear' on the: CC Radio Plus, Sony ICF-2010,
Grundig Satellit 800 M, and Grundig S350.

Could this be KSFH or some LPFM 'pirate' ?

NOTE: I have not heard a Station ID and the Old Time Radio
Programs are giving the original ABC-CBS-NBC Radio Network IDs
and vintage radio commercials from that era.

On their website KSFH claims:
"KSFH is also the only station licensed in the United States to
broadcast on 87.9 FM. Screaming loud audio from our Mackie
Production system amplified through an Orban 8200 Audio Processor
blankets 750 square miles of Silicon Valley."
= This would be a 27+ Miles-to-a-Side Square.

FCC estimates a 2-3 Mile Signal Pattern for KSFH:
http://www.fcc.gov/fcc-bin/FMTV-serv...=FM285006.html

St. Francis High School of Mountain View
LOCATION= http://tinyurl.com/4vqvw
1885 Miramonte Avenue
Mountain View, CA 94040

Antenna Location: I would appear that the Transmitting Antenna
is located on the School's grounds.

NOTE: Use of Channel 200 [87.9 MHz] is restricted to existing
displaced full service Class D noncommercial educational
stations. See 47 CFR 73.501. Channel 200 is not available for
use by other station classes and services.
http://www.fcc.gov/fcc-bin/fmq?list=0&facid=62118

~ RHF
.
.
= = = (Radioman390) wrote in message
= = = ...
I'm in Mountain View, CA and trying to find station KSFH-FM, which is an
FCC-licensed Class "D" station. It is owner by a local school, and when I call
them they say they're on the air with programming. I am 1 mile from the campus
and can SEE the antenna. I tune to every channel from 88.1 to 107.9 MHz.
Nothing, except, of course, the other stations normally heard. I also try
holding my antenna sideway, vertical, every which way.
I call the FCC office in San Francisco and they say yes they're a legal
station, and they should reach at least 3 miles, so try again. Again nothing.
What is going on?
.

= = =
= = = (Bart Z. Lederman) wrote in message
= = = ...

Could someone please tell me when 87.9 became a legal frequency?

BZL,

ONCE AGAIN FROM MY ORIGINAL POST:

NOTE: Use of Channel 200 [87.9 MHz] is restricted to existing
displaced full service Class D noncommercial educational
stations. See 47 CFR 73.501. Channel 200 is not available for
use by other station classes and services.
http://www.fcc.gov/fcc-bin/fmq?list=0&facid=62118

READ: 47 CFR 73.501 = http://tinyurl.com/6pyl7
http://frwebgate.access.gpo.gov/cgi-bin/get-cfr.cgi?TITLE=47&PART=73&SECTION=501&YEAR=2002&TYP E=TEXT

Frequency 87.9 MHz for Channel # 200 *

* NOTE: The frequency 87.9 MHz, Channel 200, is available only
for use of existing Class D stations required to change frequency.
It is available only on a noninterference basis with respect to
TV Channel 6 stations and adjacent channel noncommercial educational
FM stations. It is not available at all within 402 kilometers
(250 miles) of Canada and 320 kilometers (199 miles) of Mexico.
The specific standards governing its use are contained in Sec. 73.512.

~ RHF
..
..

All of my references (which I admit are many years old) says the
band starts at 88.1

The encyclopedia reference given previously doesn't seem to say when
the change was made.

Thanks.

--
B. Z. Lederman Personal Opinions Only

Posting to a News group does NOT give anyone permission
to send me advertising by E-mail or put me on a mailing
list of any kind.

Please remove the "DISABLE-JUNK-EMAIL" if you have a
legitimate reason to E-mail a response to this post.
..