Any audible signals on a 40 Hz AM radio?
 

Hi:

What would be heard on a 40 Hz AM DX receiver that uses the most
sensitive type of magnetic loop antenna? I doubt there would be any
hissing since that artifact would involve high-frequency sounds and a
40 Hz carrier cannot transport modulation-signals higher than 40 Hz
[violation of Nyquist theorem].

I also don't think power lines would have any perceptible affect on a
40 Hz receiver. In USA, the electric power has a frequency of 60 Hz --
in Europe, its 50 Hz. Since 40 Hz is below these power frequencies, I
doubt they would cause interference on 40 Hz. If I was receiving at or
above the power frequencies, I do think there would be disturbance but
not if below.

Would any interferences from outer space be perceptible on a 40 Hz AM
receiver? Galactic noise?


Thanks,

Radium

Any audible signals on a 40 Hz AM radio?
 

He's baaaaaaaack.

Any audible signals on a 40 Hz AM radio?
 

In rec.radio.amateur.antenna Green Xenon [Radium] wrote:
Hi:

What would be heard on a 40 Hz AM DX receiver that uses the most
sensitive type of magnetic loop antenna? I doubt there would be any
hissing since that artifact would involve high-frequency sounds and a
40 Hz carrier cannot transport modulation-signals higher than 40 Hz
[violation of Nyquist theorem].

Most likely YOU would hear "Hab SoslI' Quch!" (your mother has a
smooth forehead!) as this is the command and control frequency for
Klingon Battle Cruisers.

--
Jim Pennino

Remove .spam.sux to reply.

Any audible signals on a 40 Hz AM radio?
 

Green Xenon [Radium] wrote:

...
Would any interferences from outer space be perceptible on a 40 Hz AM
receiver? Galactic noise?


Thanks,

Radium

Possibly "bleedover" from some guy next door operating his subwoofer(s),
60Hz equip., noise, etc. ...

Why not just run a big loop of wire about and hook it to the mic/aux.
input on some old high quality/low-audio-freq. capable stereo? You
could catch all the "bands" from 20Hz-40,000Hz! LOL

Regards,
JS

--
loudobbs.com -- you do have the power to be informed; but, first you
have to use it.

Any audible signals on a 40 Hz AM radio?
 

"Green Xenon [Radium]" wrote in message
...
Hi:

What would be heard on a 40 Hz AM DX receiver that uses the most
sensitive type of magnetic loop antenna? I doubt there would be any
hissing since that artifact would involve high-frequency sounds and a
40 Hz carrier cannot transport modulation-signals higher than 40 Hz
[violation of Nyquist theorem].

I also don't think power lines would have any perceptible affect on a
40 Hz receiver. In USA, the electric power has a frequency of 60 Hz --
in Europe, its 50 Hz. Since 40 Hz is below these power frequencies, I
doubt they would cause interference on 40 Hz. If I was receiving at or
above the power frequencies, I do think there would be disturbance but
not if below.

Would any interferences from outer space be perceptible on a 40 Hz AM
receiver? Galactic noise?


Thanks,

Radium

hey, its our favorite troll next to art back for more abuse... you should
really talk to art, he'll build you a 40hz antenna that you can aim like a
laser beam and see just what you can hear. why don't you ask the elf
researchers what they 'hear' at those frequencies.

Any audible signals on a 40 Hz AM radio?
 

On Sep 12, 4:22 pm, "Green Xenon [Radium]"
wrote:
Hi:

What would be heard on a 40 Hz AM DX receiver that uses the most
sensitive type of magnetic loop antenna? I doubt there would be any
hissing since that artifact would involve high-frequency sounds and a
40 Hz carrier cannot transport modulation-signals higher than 40 Hz
[violation of Nyquist theorem].

I also don't think power lines would have any perceptible affect on a
40 Hz receiver. In USA, the electric power has a frequency of 60 Hz --
in Europe, its 50 Hz. Since 40 Hz is below these power frequencies, I
doubt they would cause interference on 40 Hz. If I was receiving at or
above the power frequencies, I do think there would be disturbance but
not if below.

Would any interferences from outer space be perceptible on a 40 Hz AM
receiver? Galactic noise?

Thanks,

Radium

Heya ass-spelunker, I see you didn't take my advice to commit suicide
last year. But if you're gonna hang around here, I have to warn you
that a couple here got a real boner for you, especially Clowney. He
unveiled a secret to me -- told me that asspie's asses taste like
honey (hey, why do you think they call 'em "asspies.") Now, take my
advice and reject any advances these predators make on you. We don't
wanna turn you into a butt-hurt serial killer now. Avoid Clowney at
all costs -- notice how excited he is to have you back.

Any audible signals on a 40 Hz AM radio?
 

On Fri, 12 Sep 2008 15:22:43 -0700 (PDT), "Green Xenon [Radium]"
wrote:

What would be heard on a 40 Hz AM DX receiver

Very slow morse code. That's about the only form of AM modulation
that will work with such a low carrier frequency.

that uses the most
sensitive type of magnetic loop antenna?

I doubt there would be any
hissing since that artifact would involve high-frequency sounds and a
40 Hz carrier cannot transport modulation-signals higher than 40 Hz
[violation of Nyquist theorem].

Well, if your carrier frequency is 40 Hz, the highest AM modulation
frequency that will work will be 20Hz. That's also approximately the
modulation bandwidth. There are a few young individuals that can hear
down to 10-30Hz, but most people can't. It's a form of hiss, but at a
much lower fequency.

I also don't think power lines would have any perceptible affect on a
40 Hz receiver. In USA, the electric power has a frequency of 60 Hz --
in Europe, its 50 Hz. Since 40 Hz is below these power frequencies, I
doubt they would cause interference on 40 Hz. If I was receiving at or
above the power frequencies, I do think there would be disturbance but
not if below.

Think again. It really depends on your receiver bandwidth. For AM,
it's going to have a fairly wide IF bandwidth in order to work at a
40Hz carrier. Although power line 60Hz will not be directly coupled
into the receiver, there's probably enough gain after the filter to
cause some problems. It's difficult to tell without clues about the
rx gain distribution and antenna configuration.

Would any interferences from outer space be perceptible on a 40 Hz AM
receiver? Galactic noise?

Not outer space. However, there is a substantial amount of
atomospheric noise at low frequencies, mostly from lightning and
atmospheric electricity discharges.
http://en.wikipedia.org/wiki/Atmospheric_noise
That's one reason why it's not useful to build an extremely sensitive
VLF receiver. Whatever you're trying to hear, it literally buried in
atmospheric noise.

Thanks,
Radium

Give up.


--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Any audible signals on a 40 Hz AM radio?
 

Green Xenon [Radium] wrote:
Hi:

What would be heard on a 40 Hz AM DX receiver that uses the most
sensitive type of magnetic loop antenna? I doubt there would be any
hissing since that artifact would involve high-frequency sounds and a
40 Hz carrier cannot transport modulation-signals higher than 40 Hz
[violation of Nyquist theorem].

Not strictly true I think - depends on the modulation scheme - how else
do you think we manage to get 56K bps down a 3KHz phone line.

Cheers

IAn

Any audible signals on a 40 Hz AM radio?
 

"Ian Thompson-Bell" wrote in message
...
Green Xenon [Radium] wrote:
Hi:

What would be heard on a 40 Hz AM DX receiver that uses the most
sensitive type of magnetic loop antenna? I doubt there would be any
hissing since that artifact would involve high-frequency sounds and a
40 Hz carrier cannot transport modulation-signals higher than 40 Hz
[violation of Nyquist theorem].

Not strictly true I think - depends on the modulation scheme - how else do
you think we manage to get 56K bps down a 3KHz phone line.

Cheers

IAn

if you really want to have fun try plugging in a 40hz carrier with a 100hz
modulation and do the sum and difference frequencies to find the
sidebands... how do you explain negative frequencies?? are they going back
in time? taking information to before it was sent? or do they appear
before the signal starts?

Any audible signals on a 40 Hz AM radio?
 

Dave wrote:
how do you explain negative frequencies??


are they going back in time?
No.

taking information to before it was sent?
No.

or do they appear before the signal starts?
No.


A phase inversion is all there is to it.

Any audible signals on a 40 Hz AM radio?
 

"Jorden Verwer" wrote in message
nl.net...
Dave wrote:
how do you explain negative frequencies??


are they going back in time?
No.

taking information to before it was sent?
No.

or do they appear before the signal starts?
No.


A phase inversion is all there is to it.


oh, you're no fun! i was looking for a lively debate of the possibilities
of sending the winning lottery numbers back in time with the negative
frequencies... that would keep radium busy for days!

Any audible signals on a 40 Hz AM radio?
 

On Sat, 13 Sep 2008 08:42:53 +0100, Ian Thompson-Bell
wrote:

Green Xenon [Radium] wrote:
Hi:

What would be heard on a 40 Hz AM DX receiver that uses the most
sensitive type of magnetic loop antenna? I doubt there would be any
hissing since that artifact would involve high-frequency sounds and a
40 Hz carrier cannot transport modulation-signals higher than 40 Hz
[violation of Nyquist theorem].

Not strictly true I think - depends on the modulation scheme - how else
do you think we manage to get 56K bps down a 3KHz phone line.

Ummm... Mr Radium clearly specified that he's using AM as in amplitude
modulation. If there were a different method of modulation employed,
methinks he would have specified it. You can get more bits per baud
out of relatively narrow bandwidths. The various HDRadio schemes:
http://en.wikipedia.org/wiki/HD_Radio
are good examples with about 40Kbits/sec in a 9KHz bandwidth. However,
they don't use AM.


--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Any audible signals on a 40 Hz AM radio?
 

Ian Thompson-Bell wrote:
Green Xenon [Radium] wrote:
Hi:

What would be heard on a 40 Hz AM DX receiver that uses the most
sensitive type of magnetic loop antenna? I doubt there would be any
hissing since that artifact would involve high-frequency sounds and a
40 Hz carrier cannot transport modulation-signals higher than 40 Hz
[violation of Nyquist theorem].

Not strictly true I think - depends on the modulation scheme - how else
do you think we manage to get 56K bps down a 3KHz phone line.

Cheers

IAn

Ian;

If it were possible to utilize 40hz at a high data rate it wouldn't take
15 minutes for the US Navy to send a 3 character message to it's
submerged submarines. As for the phone companies sending 56kbps down a
3khz phone line. They use something like 4 descrete tones and phase
shifts to do that and not at the rated speed either but something less
as a practical matter.

Dave WD9BDZ

Any audible signals on a 40 Hz AM radio?
 

Jeff Liebermann wrote:
On Sat, 13 Sep 2008 08:42:53 +0100, Ian Thompson-Bell
wrote:

Green Xenon [Radium] wrote:
Hi:

What would be heard on a 40 Hz AM DX receiver that uses the most
sensitive type of magnetic loop antenna? I doubt there would be any
hissing since that artifact would involve high-frequency sounds and a
40 Hz carrier cannot transport modulation-signals higher than 40 Hz
[violation of Nyquist theorem].
Not strictly true I think - depends on the modulation scheme - how else
do you think we manage to get 56K bps down a 3KHz phone line.

Ummm... Mr Radium clearly specified that he's using AM as in amplitude
modulation. If there were a different method of modulation employed,
methinks he would have specified it. You can get more bits per baud
out of relatively narrow bandwidths. The various HDRadio schemes:
http://en.wikipedia.org/wiki/HD_Radio
are good examples with about 40Kbits/sec in a 9KHz bandwidth. However,
they don't use AM.




Depends on your definition of AM. There are many types of amplitude
modulation, ask any radio amateur - and then of course there's VPAM.

Cheers

Ian

Any audible signals on a 40 Hz AM radio?
 

David G. Nagel wrote:
Ian Thompson-Bell wrote:
Green Xenon [Radium] wrote:
Hi:

What would be heard on a 40 Hz AM DX receiver that uses the most
sensitive type of magnetic loop antenna? I doubt there would be any
hissing since that artifact would involve high-frequency sounds and a
40 Hz carrier cannot transport modulation-signals higher than 40 Hz
[violation of Nyquist theorem].

Not strictly true I think - depends on the modulation scheme - how
else do you think we manage to get 56K bps down a 3KHz phone line.

Cheers

IAn

Ian;

If it were possible to utilize 40hz at a high data rate it wouldn't take
15 minutes for the US Navy to send a 3 character message to it's
submerged submarines.

That's becuase the technology was developed ages ago.

As for the phone companies sending 56kbps down a
3khz phone line. They use something like 4 descrete tones and phase
shifts to do that and not at the rated speed either but something less
as a practical matter.
.

Multiphase AM schemes are common place; they are used in mobile phones
for instance. It's the old trade off between bandwidth and S/N just like
in FM but in reverse. Check out VPAM.

Cheers

Ian

Any audible signals on a 40 Hz AM radio?
 

You guys are all dupes who have fallen for "Radium"s
old tricks of asking insane questions and then sitting back
and laughing at people trying to make sense of them.

"Radium" is a notorious, long-time Usenet Troll. There
is absolutely no future in trying to reply to any of his/
her/it's questions.

Any audible signals on a 40 Hz AM radio?
 

Richard Crowley wrote:
You guys are all dupes who have fallen for "Radium"s
old tricks of asking insane questions and then sitting back
and laughing at people trying to make sense of them.

"Radium" is a notorious, long-time Usenet Troll. There
is absolutely no future in trying to reply to any of his/
her/it's questions.


Actually, I think each and every poster should be given all the respect
which his/hers/its'/??? question deserves ... which I did! :-P

Regards,
JS

Any audible signals on a 40 Hz AM radio?
 

"Richard Crowley" wrote in message
. ..
You guys are all dupes who have fallen for "Radium"s
old tricks of asking insane questions and then sitting back
and laughing at people trying to make sense of them.

"Radium" is a notorious, long-time Usenet Troll. There
is absolutely no future in trying to reply to any of his/
her/it's questions.

who is trying to make sense?? its better, and more fun, to add to the
stupidness of it... much like answering art. a troll is a troll is a
troll... bait them and have fun.

Any audible signals on a 40 Hz AM radio?
 

"Dave" wrote ...
"Richard Crowley" wrote ...
You guys are all dupes who have fallen for "Radium"s
old tricks of asking insane questions and then sitting back
and laughing at people trying to make sense of them.

"Radium" is a notorious, long-time Usenet Troll. There
is absolutely no future in trying to reply to any of his/
her/it's questions.

who is trying to make sense?? its better, and more fun, to add to the
stupidness of it... much like answering art. a troll is a troll is a
troll... bait them and have fun.

Yeah, I like having nonsense fun as much as the next guy.
But "Radium" seems incapable of distinguishing between
nonsense and actual technical discussion. It just encourages him.

Any audible signals on a 40 Hz AM radio?
 

In article ,
Ian Thompson-Bell wrote:

Green Xenon [Radium] wrote:
Hi:

What would be heard on a 40 Hz AM DX receiver that uses the most
sensitive type of magnetic loop antenna? I doubt there would be any
hissing since that artifact would involve high-frequency sounds and a
40 Hz carrier cannot transport modulation-signals higher than 40 Hz
[violation of Nyquist theorem].

Not strictly true I think - depends on the modulation scheme - how else
do you think we manage to get 56K bps down a 3KHz phone line.

Because it's not the *line* that limits the rate; it's gear at the
central office. Even so, 56k modems need to cleverly bypass some of the
CO stuff.

By using clever modulation techniques and error correction, a nominal
3600 Hz analog telco channel can manage about 32 kbps, but in that case,
the symbol rate (baud rate) is 2400 baud per second, well within the
passband of the channel.

Isaac

Any audible signals on a 40 Hz AM radio?
 

In article ,
Ian Thompson-Bell wrote:

David G. Nagel wrote:
Ian Thompson-Bell wrote:
Green Xenon [Radium] wrote:
Hi:

What would be heard on a 40 Hz AM DX receiver that uses the most
sensitive type of magnetic loop antenna? I doubt there would be any
hissing since that artifact would involve high-frequency sounds and a
40 Hz carrier cannot transport modulation-signals higher than 40 Hz
[violation of Nyquist theorem].

Not strictly true I think - depends on the modulation scheme - how
else do you think we manage to get 56K bps down a 3KHz phone line.

Cheers

IAn

Ian;

If it were possible to utilize 40hz at a high data rate it wouldn't take
15 minutes for the US Navy to send a 3 character message to it's
submerged submarines.

That's becuase the technology was developed ages ago.

Actually, the primary thing controlling VLF radio data rates is the
bandwidth of the antenna -- the signal just can't build up and decay
fast enough for a higher rate.

Isaac

Any audible signals on a 40 Hz AM radio?
 

"Richard Crowley" wrote:
You guys are all dupes who have fallen for "Radium"s
old tricks of asking insane questions and then sitting back
and laughing at people trying to make sense of them.

"Radium" is a notorious, long-time Usenet Troll. There
is absolutely no future in trying to reply to any of his/
her/it's questions.
Imagine this: Radium, Art, and Fractenna in the same room,
having a discussion about antennas. And of course you would
need someone to moderate,,, maybe Cecil.

Mike W5CHR
Memphis Tenn

Any audible signals on a 40 Hz AM radio?
 

Mike Lucas wrote:

...
need someone to moderate,,, maybe Cecil.

Mike W5CHR
Memphis Tenn



Naaa. You'd want the Dipole Dummy, complete with his full works of
articles/texts from the late 1800's clear into the early 1930's! ROFLOL

Regards,
JS

Any audible signals on a 40 Hz AM radio?
 

Mike Lucas wrote:
"Richard Crowley" wrote:
You guys are all dupes who have fallen for "Radium"s
old tricks of asking insane questions and then sitting back
and laughing at people trying to make sense of them.

"Radium" is a notorious, long-time Usenet Troll. There
is absolutely no future in trying to reply to any of his/
her/it's questions.
Imagine this: Radium, Art, and Fractenna in the same room,
having a discussion about antennas. And of course you would
need someone to moderate,,, maybe Cecil.

Mike W5CHR
Memphis Tenn


What are you trying to do, kill us with laughter? ;^)

Dave WD9BDZ

Any audible signals on a 40 Hz AM radio?
 

"Richard Crowley" wrote in message
...
"Dave" wrote ...
"Richard Crowley" wrote ...
You guys are all dupes who have fallen for "Radium"s
old tricks of asking insane questions and then sitting back
and laughing at people trying to make sense of them.

"Radium" is a notorious, long-time Usenet Troll. There
is absolutely no future in trying to reply to any of his/
her/it's questions.

who is trying to make sense?? its better, and more fun, to add to the
stupidness of it... much like answering art. a troll is a troll is a
troll... bait them and have fun.

Yeah, I like having nonsense fun as much as the next guy.
But "Radium" seems incapable of distinguishing between
nonsense and actual technical discussion. It just encourages him.
thats the whole idea!

Any audible signals on a 40 Hz AM radio?
 

Amateur Radio Study Guides say radio (carrier) waves start at approx. 20,000
hertz...............


"Green Xenon [Radium]" wrote in message
...
Hi:

What would be heard on a 40 Hz AM DX receiver that uses the most
sensitive type of magnetic loop antenna? I doubt there would be any
hissing since that artifact would involve high-frequency sounds and a
40 Hz carrier cannot transport modulation-signals higher than 40 Hz
[violation of Nyquist theorem].

I also don't think power lines would have any perceptible affect on a
40 Hz receiver. In USA, the electric power has a frequency of 60 Hz --
in Europe, its 50 Hz. Since 40 Hz is below these power frequencies, I
doubt they would cause interference on 40 Hz. If I was receiving at or
above the power frequencies, I do think there would be disturbance but
not if below.

Would any interferences from outer space be perceptible on a 40 Hz AM
receiver? Galactic noise?


Thanks,

Radium

Any audible signals on a 40 Hz AM radio?
 

"Rollie" wrote in message
...
Amateur Radio Study Guides say radio (carrier) waves start at approx.
20,000 hertz...............


"Green Xenon [Radium]" wrote in message
...
Hi:

What would be heard on a 40 Hz AM DX receiver that uses the most
sensitive type of magnetic loop antenna? I doubt there would be any
hissing since that artifact would involve high-frequency sounds and a
40 Hz carrier cannot transport modulation-signals higher than 40 Hz
[violation of Nyquist theorem].

I also don't think power lines would have any perceptible affect on a
40 Hz receiver. In USA, the electric power has a frequency of 60 Hz --
in Europe, its 50 Hz. Since 40 Hz is below these power frequencies, I
doubt they would cause interference on 40 Hz. If I was receiving at or
above the power frequencies, I do think there would be disturbance but
not if below.

Would any interferences from outer space be perceptible on a 40 Hz AM
receiver? Galactic noise?


Thanks,

Radium


What about VLF communications from submerged submarines? They work at, would
you believe, Very Low Frequencies, a lot lower than 20kHz.

S.
--
http://audiopages.googlepages.com

Any audible signals on a 40 Hz AM radio?
 

Green Xenon [Radium] wrote:
Hi:

What would be heard on a 40 Hz AM DX receiver that uses the most
sensitive type of magnetic loop antenna?

Around 40 Hertz, tops.


- 73 de Mike N3LI -