Indoor FM boost with no cables?
 

Lostgallifreyan wrote:
Jerry Stuckle wrote in news:lriogq$kba$1@dont-
email.me:

In an FM transmitter, the amount of deviation is proportional to the
amplitude of the modulating signal. That is, the louder the audio, the
greater the deviation.

Transmitter bandwidth cannot be greater than receiver bandwidth without
loss of signal and distortion. Transmitter deviation can be less than
receiver bandwidth; this only results in lower audio. This is why
commercial FM receivers typically have a bandwidth of 170-180 kHz, when
deviation is only 75 kHz. It makes things less critical.


Ok, so a kind of 'headroom' exists then, but is there some agreeable degree
of reduction on transmitter bandwidth to gain a significant reach in RF
propagation and reduction in intrusion across the band, before the whole
exercise fails due to poor SNR on output? My guess is that there may be, but
the decision could be very different depending on whether speech or music
(let alone stereo) is wanted.

Deviation is something different than bandwidth. To receive an FM signal,
as a rule of thumb you require a receiver with a bandwith of about
twice the deviation plus twice the maximal audio frequency. So to receive
a signal with 15kHz audio and 75kHz deviation, you require a bandwitdh
of about 180kHz.

This is not "to make things less critical". It is a requirement because
of the characteristics of FM modulation, where sideband frequencies are
determined by a Bessel function.

The ratio between deviation and maximal audio frequency, the modulation
index, determines the signal/noise ratio after demodulation for a strong
signal. So for music transmissions on the FM broadcast band a larger
modulation index (about 5) is used than for communication (usually 1 or
a bit less). That means at typical signal strengths encountered in
broadcast use, the signal/noise ratio is better than for small modulation
index.
(for weak-signal work, where you are looking for an intelligible signal
and not for lowest noise, a smaller modulation index performs better
because you can use a narrower receiver bandwidth)

Indoor FM boost with no cables?
 

Lostgallifreyan wrote:
Jerry Stuckle wrote in news:lrio4f$fs4$1@dont-
email.me:

Nope. I'm talking about what is commonly used here. But there are some
people from the U.K. who think they are experts on everything.


To be fair to him, I'm in the UK and he may well have aimed that point at me,
knowing this from the message header or some earlier post of mine. I'm
also interesed in how the US conventions differ from ours.

I think you should be careful not to mistake Jerry's conventions
for US conventions. It looks a lot like Jerry makes many assumptions
that are not based on signal theory or common practice, but mainly on
his own experience as a cable fitter.

Indoor FM boost with no cables?
 

On 8/2/2014 4:11 PM, Lostgallifreyan wrote:
Jeff wrote in :

The bandwidth does not have to match exactly, but it it is too much then
it will distort as it exceeds the Bandwidth if the IF filters in the
receiver, and if it is too low the volume out of the receiver will be
low, so you would have to turn up the volume control when you used the
device. If it were extremely low then the audio would be very quiet
indeed, and if the signal strength were also too low you would loose
everything in noise.

The nominal max deviation in the FM broadcast band is +/-75kHz (150kHz
total).


Thanks. It looks like matching is best for compromise then, not some value
for transmission lower than reception, because what you gain in RF reach you
lose in SNR on output so striving for anything but a good match looks like a
game of diminishing returns.


I probably missed something in this thread, but where are you going to
get an FM transmitter that isn't designed to work with FM radios?

Mikek

Indoor FM boost with no cables?
 

On 8/1/2014 6:32 PM, Lostgallifreyan wrote:
amdx wrote in :

PS, I'll bet both of you stations stream on the internet. If you
have wifi, that will eliminate your noise problem.


I get capped at 10GB per month, and that costs far too much. If I saw the
costs of the bandwidth to do this I might scream loud enough that even my
neighbours might have a noise problem. :) Besides, good FM totally beats all
internet quality. Radio 3's best HD sound falls well short, equivalent to a
192 kbps MP3 at best, from what I have read and heard about it. FM in the UK
is extremely good quality, nothing else has been any better yet. Which is
probably why obituary after obituary gets written for broadcast FM radio, btu
it never dies, the 'swicth-off date' is forver being set back, and it likely
won't happen once peoplerealise the costs of allocating bandwidth foe that
kind of quality ona per-person basis! That's a mind-stunning financial and
technical calculation no matter how we look at it.


Ok, high fidelity is not important for what I listen to which is
mostly speech. I listen to old time radio programs on Old Time Radio,
All Time Radio Oldies Radio Theater, and 20th Century Radio (OTR).
I also listen to a lot Science 360 and then other talk radio programs.

For those interested this is where you set up the stations for an
internet radio.
I think you can check the station list (19,000 stations), possible you
need to put in your internet radio info to search, I don't know.
https://radios.reciva.com/

Mikek

Indoor FM boost with no cables?
 

On 8/2/2014 5:53 PM, Rob wrote:
Lostgallifreyan wrote:
Jerry Stuckle wrote in news:lrio4f$fs4$1@dont-
email.me:

Nope. I'm talking about what is commonly used here. But there are some
people from the U.K. who think they are experts on everything.


To be fair to him, I'm in the UK and he may well have aimed that point at me,
knowing this from the message header or some earlier post of mine. I'm
also interesed in how the US conventions differ from ours.

I think you should be careful not to mistake Jerry's conventions
for US conventions. It looks a lot like Jerry makes many assumptions
that are not based on signal theory or common practice, but mainly on
his own experience as a cable fitter.


Cabling is not the only thing I do - nor the only thing I have done in
the past. It is just one of the things my company does.

But like other trolls, you think you know everything, when you actually
know nothing.

So much for the anonymous troll who uses a fake email and probably
doesn't even have a call sign.

--
==================
Remove the "x" from my email address
Jerry, AI0K

==================

Indoor FM boost with no cables?
 

Jerry Stuckle wrote:
On 8/2/2014 5:53 PM, Rob wrote:
Lostgallifreyan wrote:
Jerry Stuckle wrote in news:lrio4f$fs4$1@dont-
email.me:

Nope. I'm talking about what is commonly used here. But there are some
people from the U.K. who think they are experts on everything.


To be fair to him, I'm in the UK and he may well have aimed that point at me,
knowing this from the message header or some earlier post of mine. I'm
also interesed in how the US conventions differ from ours.

I think you should be careful not to mistake Jerry's conventions
for US conventions. It looks a lot like Jerry makes many assumptions
that are not based on signal theory or common practice, but mainly on
his own experience as a cable fitter.


Cabling is not the only thing I do - nor the only thing I have done in
the past. It is just one of the things my company does.

But like other trolls, you think you know everything, when you actually
know nothing.

So much for the anonymous troll who uses a fake email and probably
doesn't even have a call sign.

I do have a college degree as an electronics engineer, so I do have the
theoretical background that you so sorely lack.

I have posted for many years under my full name, callsign and e-mail
address, but I have chosen to stop doint that. Many know who I am.

Indoor FM boost with no cables?
 

On 8/2/2014 7:10 PM, Rob wrote:
Jerry Stuckle wrote:
On 8/2/2014 5:53 PM, Rob wrote:
Lostgallifreyan wrote:
Jerry Stuckle wrote in news:lrio4f$fs4$1@dont-
email.me:

Nope. I'm talking about what is commonly used here. But there are some
people from the U.K. who think they are experts on everything.


To be fair to him, I'm in the UK and he may well have aimed that point at me,
knowing this from the message header or some earlier post of mine. I'm
also interesed in how the US conventions differ from ours.

I think you should be careful not to mistake Jerry's conventions
for US conventions. It looks a lot like Jerry makes many assumptions
that are not based on signal theory or common practice, but mainly on
his own experience as a cable fitter.


Cabling is not the only thing I do - nor the only thing I have done in
the past. It is just one of the things my company does.

But like other trolls, you think you know everything, when you actually
know nothing.

So much for the anonymous troll who uses a fake email and probably
doesn't even have a call sign.

I do have a college degree as an electronics engineer, so I do have the
theoretical background that you so sorely lack.

I have posted for many years under my full name, callsign and e-mail
address, but I have chosen to stop doint that. Many know who I am.


So you claim. But you're just an anonymous troll with no call sign and
an invalid email address. As for the degree - IF you ever had one
(which I doubt), it was probably mail order from one of the diploma mills.

--
==================
Remove the "x" from my email address
Jerry, AI0K

==================

Indoor FM boost with no cables?
 

Jerry Stuckle wrote:
On 8/2/2014 7:10 PM, Rob wrote:
Jerry Stuckle wrote:
On 8/2/2014 5:53 PM, Rob wrote:
Lostgallifreyan wrote:
Jerry Stuckle wrote in news:lrio4f$fs4$1@dont-
email.me:

Nope. I'm talking about what is commonly used here. But there are some
people from the U.K. who think they are experts on everything.


To be fair to him, I'm in the UK and he may well have aimed that point at me,
knowing this from the message header or some earlier post of mine. I'm
also interesed in how the US conventions differ from ours.

I think you should be careful not to mistake Jerry's conventions
for US conventions. It looks a lot like Jerry makes many assumptions
that are not based on signal theory or common practice, but mainly on
his own experience as a cable fitter.


Cabling is not the only thing I do - nor the only thing I have done in
the past. It is just one of the things my company does.

But like other trolls, you think you know everything, when you actually
know nothing.

So much for the anonymous troll who uses a fake email and probably
doesn't even have a call sign.

I do have a college degree as an electronics engineer, so I do have the
theoretical background that you so sorely lack.

I have posted for many years under my full name, callsign and e-mail
address, but I have chosen to stop doint that. Many know who I am.


So you claim. But you're just an anonymous troll with no call sign and
an invalid email address. As for the degree - IF you ever had one
(which I doubt), it was probably mail order from one of the diploma mills.

I see you have been in that business, so you probably consider that normal.
But this is not the US, and those practices are not that common here.
(certainly not when I got my degree)

Indoor FM boost with no cables?
 

Jerry Stuckle wrote:
On 8/2/2014 5:53 PM, Rob wrote:
Lostgallifreyan wrote:
Jerry Stuckle wrote in news:lrio4f$fs4$1@dont-
email.me:

Nope. I'm talking about what is commonly used here. But there are some
people from the U.K. who think they are experts on everything.


To be fair to him, I'm in the UK and he may well have aimed that point at me,
knowing this from the message header or some earlier post of mine. I'm
also interesed in how the US conventions differ from ours.

I think you should be careful not to mistake Jerry's conventions
for US conventions. It looks a lot like Jerry makes many assumptions
that are not based on signal theory or common practice, but mainly on
his own experience as a cable fitter.


Cabling is not the only thing I do - nor the only thing I have done in
the past. It is just one of the things my company does.

But like other trolls, you think you know everything, when you actually
know nothing.

So much for the anonymous troll who uses a fake email and probably
doesn't even have a call sign.


And here he goes off into his usual "stupid troll" rant with yet a person
who had the umitigated audacity to imply Jerry Stuckle does not know
everything about everything.

You ignorant peasants just don't understand; Jerry Stuckle has done
everything, knows everything and is NEVER, EVER wrong about anything.

To even hint otherwise is blasphemy and you shall be severely reprimanded
and totally disparaged as you well deserve.


--
Jim Pennino

Indoor FM boost with no cables?
 

On 8/2/2014 7:38 PM, Rob wrote:
Jerry Stuckle wrote:
On 8/2/2014 7:10 PM, Rob wrote:
Jerry Stuckle wrote:
On 8/2/2014 5:53 PM, Rob wrote:
Lostgallifreyan wrote:
Jerry Stuckle wrote in news:lrio4f$fs4$1@dont-
email.me:

Nope. I'm talking about what is commonly used here. But there are some
people from the U.K. who think they are experts on everything.


To be fair to him, I'm in the UK and he may well have aimed that point at me,
knowing this from the message header or some earlier post of mine. I'm
also interesed in how the US conventions differ from ours.

I think you should be careful not to mistake Jerry's conventions
for US conventions. It looks a lot like Jerry makes many assumptions
that are not based on signal theory or common practice, but mainly on
his own experience as a cable fitter.


Cabling is not the only thing I do - nor the only thing I have done in
the past. It is just one of the things my company does.

But like other trolls, you think you know everything, when you actually
know nothing.

So much for the anonymous troll who uses a fake email and probably
doesn't even have a call sign.

I do have a college degree as an electronics engineer, so I do have the
theoretical background that you so sorely lack.

I have posted for many years under my full name, callsign and e-mail
address, but I have chosen to stop doint that. Many know who I am.


So you claim. But you're just an anonymous troll with no call sign and
an invalid email address. As for the degree - IF you ever had one
(which I doubt), it was probably mail order from one of the diploma mills.

I see you have been in that business, so you probably consider that normal.
But this is not the US, and those practices are not that common here.
(certainly not when I got my degree)


Yea, when you got your "degree". Which diploma mill did you get from -
the University of Golden Knowledge?

Fat chance. If you did have a degree, you would be able to read.
You've shown multiple times you cannot.

But you are just an anonymous troll who's afraid people will find out he
doesn't have ANY of the things he claims. And you're afraid your boss
will find out how little you know and fire you from your dishwashing job.

Once again you can have the last word. I know trolls have to have it.

--
==================
Remove the "x" from my email address
Jerry, AI0K

==================