FM Radio question

[[email protected]]

This may not be the right group, but let me throw this out to some
audio expert here.

I run a small TV studio. I need to run "audio-under" a message board
on a TV channel, and the consensus is that it should be an FM station
about 12 miles away. I use either an FM tuner (line out) or an FM
radio (headphone out, adapted to roughly line level). The problem is
reception. (It's not a city, more of a bedroom community.)

I can't seem to get a solid signal from the radio's whip antenna, or
from the tuner with a dipole. I have an FM antenna on the roof (whose
lead keeps breaking from the unusual snowfalls), but when I attach
that to the Rolls tuner, I get a more distant FM station on the same
frequency.

I can't find a directional FM antenna anywhere. Is there any way to
get my tuner or radio to get a solid FM signal from the 12-mi station
while excluding the more distant signal? Is there some sort of
external antenna I can use indoors, perhaps in the ceiling crawl
space? The radio has a PAL type connector, and the Rolls has a twin
lead connector.

Any suggestions?

[John Williamson]

wrote:
> This may not be the right group, but let me throw this out to some
> audio expert here.
>
>
> I can't find a directional FM antenna anywhere. Is there any way to
> get my tuner or radio to get a solid FM signal from the 12-mi station
> while excluding the more distant signal? Is there some sort of
> external antenna I can use indoors, perhaps in the ceiling crawl
> space? The radio has a PAL type connector, and the Rolls has a twin
> lead connector.
>
> Any suggestions?

Assuming the FM stations you are wanting to discriminate between are not
in the same direction:-

http://www.kenneke.com/antennas.html

Or google for FM broadcast yagi. I don't know your local market, but all
the aerial installers near me can get one quite easily, if they don't
have one in stock.

Any nearby radio amateurs may be able to build you one. They're not that
hard to make. The narrower your required beam, the longer the unit will
be, though.

Failing that, if the station has a website, they may have streaming
audio you can tap.

--
Tciao for Now!

John.

[Scott Dorsey]

> wrote:
>I can't seem to get a solid signal from the radio's whip antenna, or
>from the tuner with a dipole. I have an FM antenna on the roof (whose
>lead keeps breaking from the unusual snowfalls), but when I attach
>that to the Rolls tuner, I get a more distant FM station on the same
>frequency.

This is both the cool thing and the awful thing about FM.... capture phenomenon
means whichever station is strongest gets received solidly. If there are
multiple stations on one channel, you get the one that is strongest.

>I can't find a directional FM antenna anywhere. Is there any way to
>get my tuner or radio to get a solid FM signal from the 12-mi station
>while excluding the more distant signal? Is there some sort of
>external antenna I can use indoors, perhaps in the ceiling crawl
>space? The radio has a PAL type connector, and the Rolls has a twin
>lead connector.
>
>Any suggestions?

Get a directional antenna. There used to be a lot of them available back
when TV antenna manufacturers were a going concern. But there are still
some:

http://www.winegarddirect.com/viewitem.asp?d=Winegard-HD-HD6055P-HDPlatinum-FM-Antenna-%28HD6055P%29&p=HD6055P

This is an 8-element yagi. You won't need a rotator since you only want one
station, but you should know that the antenna pattern will change when your
body is near it, so you will need to set it, get away from it, check the
signal strength on the radio, then repoint it... and on and on until it's
in the right spot.

You may also find that because of multipath, if you move the antenna a few
feet, maybe to the other side of the roof, the desired station is stronger.
A portable radio up on the roof can help you determine if this is true.
Odds are that the signals from both of the stations aren't coming in from
direct line of sight but have been bounced off of lots of buildings or
mountains and so there are peaks and dips due to standing waves, just like
the acoustical low end problems you get in a small room.

Also, I really recommend the cheap little Sony HD tuner.... it's a hundred
bucks and the RF performance for analogue FM is excellent.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Steve King]

"Scott Dorsey" > wrote in message
...
| > wrote:
| >I can't seem to get a solid signal from the radio's whip antenna, or
| >from the tuner with a dipole. I have an FM antenna on the roof (whose
| >lead keeps breaking from the unusual snowfalls), but when I attach
| >that to the Rolls tuner, I get a more distant FM station on the same
| >frequency.
|
| This is both the cool thing and the awful thing about FM.... capture
phenomenon
| means whichever station is strongest gets received solidly. If there are
| multiple stations on one channel, you get the one that is strongest.
|
| >I can't find a directional FM antenna anywhere. Is there any way to
| >get my tuner or radio to get a solid FM signal from the 12-mi station
| >while excluding the more distant signal? Is there some sort of
| >external antenna I can use indoors, perhaps in the ceiling crawl
| >space? The radio has a PAL type connector, and the Rolls has a twin
| >lead connector.
| >
| >Any suggestions?
|
| Get a directional antenna. There used to be a lot of them available back
| when TV antenna manufacturers were a going concern. But there are still
| some:
|
|
http://www.winegarddirect.com/viewitem.asp?d=Winegard-HD-HD6055P-HDPlatinum-FM-Antenna-%28HD6055P%29&p=HD6055P
|
| This is an 8-element yagi. You won't need a rotator since you only want
one
| station, but you should know that the antenna pattern will change when
your
| body is near it, so you will need to set it, get away from it, check the
| signal strength on the radio, then repoint it... and on and on until it's
| in the right spot.
|
| You may also find that because of multipath, if you move the antenna a few
| feet, maybe to the other side of the roof, the desired station is
stronger.
| A portable radio up on the roof can help you determine if this is true.
| Odds are that the signals from both of the stations aren't coming in from
| direct line of sight but have been bounced off of lots of buildings or
| mountains and so there are peaks and dips due to standing waves, just like
| the acoustical low end problems you get in a small room.
|
| Also, I really recommend the cheap little Sony HD tuner.... it's a hundred
| bucks and the RF performance for analogue FM is excellent.
| --scott
| --
| "C'est un Nagra. C'est suisse, et tres, tres precis."

Sometimes, when dealing with interferring signals on the same frequency,
better results can be achieved by orienting the deepest null of the
directional antenna toward the unwanted station rather than just pointing
the antenna at the desired station.

Steve King

[Mark]

>
> Sometimes, when dealing with interferring signals on the same frequency,
> better results can be achieved by orienting the deepest null of the
> directional antenna toward the unwanted station rather than just pointing
> the antenna at the desired station.
>
> Steve King


to the op

it is hard to belive that a distant station would capture a full power
commerical station that is only 12 miles away. Is your desired
station a low power FM station or is there a mountain in the way? or
are you hearing interfernece from intermod or something else?

Also, if you can put your reciever in MONO mode, you will be about 12
dB better off and much less suseptable to multi-path.,...

Mark

[Scott Dorsey]

Steve King > wrote:
>
>Sometimes, when dealing with interferring signals on the same frequency,
>better results can be achieved by orienting the deepest null of the
>directional antenna toward the unwanted station rather than just pointing
>the antenna at the desired station.

Good point. And that antenna probably has a little rear lobe like a
hypercardioid mike, too.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[[email protected]]

On Feb 7, 10:20*am, John Williamson >
wrote:

> Assuming the FM stations you are wanting to discriminate between are not
> in the same direction:-

Generally not in the same direction.

>
> http://www.kenneke.com/antennas.html

These appear to be for a person TRANSMITTING. Can they also be used to
receive, directionally?

>
> Or google for FM broadcast yagi. I don't know your local market, but all
> the aerial installers near me can get one quite easily, if they don't
> have one in stock.
>
> Any nearby radio amateurs may be able to build you one. They're not that
> hard to make. The narrower your required beam, the longer the unit will
> be, though.
>
> Failing that, if the station has a website, they may have streaming
> audio you can tap.

I tried that, but every time there's an AC or internet hiccup, I lose
it and have to drive to the station to re-establish it.

>
> --
> Tciao for Now!
>
> John.

[[email protected]]

On Feb 7, 10:35*am, (Scott Dorsey) wrote:

> Get a directional antenna. *There used to be a lot of them available back
> when TV antenna manufacturers were a going concern. *But there are still
> some:
>
> http://www.winegarddirect.com/viewitem.asp?d=Winegard-HD-HD6055P-HDPl....

This looks interesting, might be just what I need. I wonder why I
couldn't find it, Googling? I went to Winegard...

>
> This is an 8-element yagi. *You won't need a rotator since you only want one
> station, but you should know that the antenna pattern will change when your
> body is near it, so you will need to set it, get away from it, check the
> signal strength on the radio, then repoint it... and on and on until it's
> in the right spot.
>
> You may also find that because of multipath, if you move the antenna a few
> feet, maybe to the other side of the roof, the desired station is stronger.

[[email protected]]

On Feb 7, 12:07*pm, "Steve King"
> wrote:

> Sometimes, when dealing with interferring signals on the same frequency,
> better results can be achieved by orienting the deepest null of the
> directional antenna toward the unwanted station rather than just pointing
> the antenna at the desired station.
>
> Steve King

Another interesting technique. The solution might be a combination of
some of the ideas here!

[[email protected]]

On Feb 7, 12:20*pm, Mark > wrote:
> > Sometimes, when dealing with interferring signals on the same frequency,
> > better results can be achieved by orienting the deepest null of the
> > directional antenna toward the unwanted station rather than just pointing
> > the antenna at the desired station.
>
> > Steve King
>
> *to the op
>
> it is hard to belive that a distant station would capture a full power
> commerical station that is only 12 miles away. *Is your desired
> station a low power FM station or is there a mountain in the way? *or
> are you hearing interfernece from intermod or something else?
>
> Also, if you can put your reciever in MONO mode, you will be about 12
> dB better off and much less suseptable to multi-path.,...
>
> Mark

[[email protected]]

On Feb 7, 12:20*pm, Mark > wrote:

>
> it is hard to belive that a distant station would capture a full power
> commerical station that is only 12 miles away. *Is your desired
> station a low power FM station or is there a mountain in the way? *or
> are you hearing interfernece from intermod or something else?

No, fairly flat suburbs. I'm in brockton MA. Station I want at 95.9 is
WATD Marshfield. Station I don't want is WBEC Pittsfield. Opposite
each other, Pittsfield is much further away!

>
> Also, if you can put your reciever in MONO mode, you will be about 12
> dB better off and much less suseptable to multi-path.,.

Yes, I have it switched to mono.
>
> Mark

[John Williamson]

wrote:
> On Feb 7, 10:20 am, John Williamson >
> wrote:
>
>> Assuming the FM stations you are wanting to discriminate between are not
>> in the same direction:-
>
> Generally not in the same direction.
>
That makes life a *lot* easier.

>> http://www.kenneke.com/antennas.html
>
> These appear to be for a person TRANSMITTING. Can they also be used to
> receive, directionally?
>
Yeah, they'll work the same both ways. Receive only is cheaper to make,
as it doesn't need to handle the power. As it's a ham radio shop, the
aerials they sell are used for both. I just used them as an example, I'd
just go to my local aerial shop. Which would be no help to you, as it's
in Stoke-on-Trent, England.

>> Or google for FM broadcast yagi. I don't know your local market, but all
>> the aerial installers near me can get one quite easily, if they don't
>> have one in stock.
>>
>> Any nearby radio amateurs may be able to build you one. They're not that
>> hard to make. The narrower your required beam, the longer the unit will
>> be, though.
>>
>> Failing that, if the station has a website, they may have streaming
>> audio you can tap.
>
> I tried that, but every time there's an AC or internet hiccup, I lose
> it and have to drive to the station to re-establish it.
>
That could be a problem....

Though it should be possible to set up a remote control for the station
over the internet or a dial up line. Laplink used to be able to do it if
there was a PC at each end of the link, though that went the way of the
Dodo when Microsoft built the same function into Windows. Linux has
always had it built in, just log in on the remote terminal and you're
there. You could even set up an automatic alert to let you know there's
a problem.

I see you've also had a few other suggestions which make good sense.

--
Tciao for Now!

John.

[Scott Dorsey]

> wrote:
>On Feb 7, 10:20=A0am, John Williamson >
>wrote:
>
>> Assuming the FM stations you are wanting to discriminate between are not
>> in the same direction:-
>
>Generally not in the same direction.
>
>>
>> http://www.kenneke.com/antennas.html
>
>These appear to be for a person TRANSMITTING. Can they also be used to
>receive, directionally?

Yes. The problem is that most transmitting antennas are rigged for 50
ohms instead of 75, and that they cost a lot more thave a receive antenna.
--scott


--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Scott Dorsey]

> wrote:
>> http://www.winegarddirect.com/viewitem.asp?d=3DWinegard-HD-HD6055P-HDPl..=
>.
>
>This looks interesting, might be just what I need. I wonder why I
>couldn't find it, Googling? I went to Winegard...

I looked in a paper Winegard catalogue and got the number. I also looked
for the Channel Master book but it's not in the right place in my office.
They make one too.

>> Also, I really recommend the cheap little Sony HD tuner.... it's a hundre=
>d
>> bucks and the RF performance for analogue FM is excellent.
>
>OOH... Got a model number?

XDR-F1HD. With it and 22 bay yagi I can get Washington DC stations from
250 miles away.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Richard Webb[_3_]]

STeve King writes:
> Sometimes, when dealing with interferring signals on the same
> frequency, better results can be achieved by orienting the deepest
> null of the directional antenna toward the unwanted station rather
> than just pointing the antenna at the desired station.

This might be the op's best bet. AS he says, thewanted
signal is an fm broadcaster 12 miles out. With an outdoor
directional antenna of any kind, even off the side he should get a signal that reasonably quiets the receiver, even if
not fully. That should let him put the deepest null which
on the Winegard fm ant I had up back in Ia. years ago, iirc
8 elements as Scott mentioned, broadside.

Regards,
Richard
--
| Remove .my.foot for email
| via Waldo's Place USA Fidonet<->Internet Gateway Site
| Standard disclaimer: The views of this user are strictly his own.

[MG[_4_]]

"Soundhaspriority" > wrote in message
...
>
> > wrote in message
> ...
> On Feb 7, 11:58 am, "Soundhaspriority" > wrote:
>> > wrote in message
>>
>> ...>
>> This may not be the right group, but let me throw this out to some
>> > audio expert here.
>>
>> > I run a small TV studio. I need to run "audio-under" a message board
>> > on a TV channel, and the consensus is that it should be an FM station
>> > about 12 miles away. I use either an FM tuner (line out) or an FM
>> > radio (headphone out, adapted to roughly line level). The problem is
>> > reception. (It's not a city, more of a bedroom community.)
>>
>> > I can't seem to get a solid signal from the radio's whip antenna, or
>> > from the tuner with a dipole. I have an FM antenna on the roof (whose
>> > lead keeps breaking from the unusual snowfalls), but when I attach
>> > that to the Rolls tuner, I get a more distant FM station on the same
>> > frequency.
>>
>> Phase cancellation can null out an unwanted
>> station:http://home.iprimus.com.au/toddemslie/phase-cancellation.html
>>
>> But the Sony tuner might just do it.
>
> Interesting Complicated, but I might be able to figure it out. Thanks!
>
>>
>> Bob Morein
>> (310) 237-6511
>
> If you don't want to build the active circuit, I think I recall how I did
> it. I built the passive circuit. Each feed was amplified by an
> off-the-shelf amp. A splitter in reverse was used to combine. A single
> rheostat in the passive shifter allowed for nulling.
>
> Bob Morein
> (310) 237-6511
>
Has the FM station agreed to this? If they have, you might be able to work
out some kind of direct feed. If you haven't, they might be unhappy with
you if they find out.

mg