There are millions of people who live in the Tornado belt. I want to
buy a Tornado warning device for my home. The National Weather service
delights in waking me up in the middle of the night if Tornado
conditions occur in the neighboring State. I want to install a device
on the roof of my house that listens for the characteristic sound of a
Tornado approaching on the ground.

Think about this problem because the solution could make you rich.

wrote:

There are millions of people who live in the Tornado belt. I want to
buy a Tornado warning device for my home. The National Weather service
delights in waking me up in the middle of the night if Tornado
conditions occur in the neighboring State.


Buy a better radio that only alerts for your area. Mine is a Midland
model.

http://www.nws.noaa.gov/nwr/nwrsame.htm

On 3/8/2013 5:57 PM, Michael A. Terrell wrote:

wrote:

There are millions of people who live in the Tornado belt. I want to
buy a Tornado warning device for my home. The National Weather service
delights in waking me up in the middle of the night if Tornado
conditions occur in the neighboring State.


Buy a better radio that only alerts for your area. Mine is a Midland
model.

http://www.nws.noaa.gov/nwr/nwrsame.htm

In the "old days" one could mistune a TV set and detect tornadoes.



Tornados create an electrical disturbance somewhere in the 55 megahertz
range, close to the frequency band assigned to channel 2. With this
phenomenon in mind, Newton Weller, an electronics technician, has
devised the following method for using your TV set as a tornado warning
device.

Tune to channel 13 and turn the brightness control down to the point
where the image is nearly--not completely--black. Then turn to channel
2. Lightning will register as horizontal streaks on the screen. When the
picture becomes bright enough to be seen, or when the screen glows with
an even light, there's a tornado within 20 miles, and it's time to find
Toto and head for the basement.

Richard wrote:

On 3/8/2013 5:57 PM, Michael A. Terrell wrote:

wrote:

There are millions of people who live in the Tornado belt. I want to
buy a Tornado warning device for my home. The National Weather service
delights in waking me up in the middle of the night if Tornado
conditions occur in the neighboring State.


Buy a better radio that only alerts for your area. Mine is a Midland
model.

http://www.nws.noaa.gov/nwr/nwrsame.htm

In the "old days" one could mistune a TV set and detect tornadoes.


Sometimes. You still didn't know the intensity, or headings though.


Tornados create an electrical disturbance somewhere in the 55 megahertz
range, close to the frequency band assigned to channel 2. With this
phenomenon in mind, Newton Weller, an electronics technician, has
devised the following method for using your TV set as a tornado warning
device.

Tune to channel 13 and turn the brightness control down to the point
where the image is nearly--not completely--black. Then turn to channel
2. Lightning will register as horizontal streaks on the screen. When the
picture becomes bright enough to be seen, or when the screen glows with
an even light, there's a tornado within 20 miles, and it's time to find
Toto and head for the basement.

On 3/8/2013 7:01 PM, Michael A. Terrell wrote:

Richard wrote:

On 3/8/2013 5:57 PM, Michael A. Terrell wrote:

wrote:

There are millions of people who live in the Tornado belt. I want to
buy a Tornado warning device for my home. The National Weather service
delights in waking me up in the middle of the night if Tornado
conditions occur in the neighboring State.


Buy a better radio that only alerts for your area. Mine is a Midland
model.

http://www.nws.noaa.gov/nwr/nwrsame.htm

In the "old days" one could mistune a TV set and detect tornadoes.


Sometimes. You still didn't know the intensity, or headings though.


That didn't matter. If channel 2 went all streaky it was time to get
below ground!

Richard wrote:

On 3/8/2013 7:01 PM, Michael A. Terrell wrote:

Richard wrote:

On 3/8/2013 5:57 PM, Michael A. Terrell wrote:

wrote:

There are millions of people who live in the Tornado belt. I want to
buy a Tornado warning device for my home. The National Weather service
delights in waking me up in the middle of the night if Tornado
conditions occur in the neighboring State.


Buy a better radio that only alerts for your area. Mine is a Midland
model.

http://www.nws.noaa.gov/nwr/nwrsame.htm

In the "old days" one could mistune a TV set and detect tornadoes.


Sometimes. You still didn't know the intensity, or headings though.


That didn't matter. If channel 2 went all streaky it was time to get
below ground!


The backgound noise was so high in some areas that it didn't give
enough warning. Not everyone had a place to hide.

On 3/8/2013 7:01 PM, Michael A. Terrell wrote:
....

Tune to channel 13 and turn the brightness control down to the point
where the image is nearly--not completely--black. Then turn to channel
2. Lightning will register as horizontal streaks on the screen. When the
picture becomes bright enough to be seen, or when the screen glows with
an even light, there's a tornado within 20 miles, ...

What makes you think that's even remotely likely to be so? Lightning
isn't at all necessarily indicative of tornadic activity--certainly
tornadoes are spawned from t-storms, but I'm pretty sure it's news to
the folks in Norman (NOAA severe weather office) there's predictive
capability in the lightning...

--

"dpb" wrote in message
...
On 3/8/2013 7:01 PM, Michael A. Terrell wrote:
...

Tune to channel 13 and turn the brightness control down to the
point
where the image is nearly--not completely--black. Then turn to
channel
2. Lightning will register as horizontal streaks on the screen.
When the
picture becomes bright enough to be seen, or when the screen glows
with
an even light, there's a tornado within 20 miles, ...

What makes you think that's even remotely likely to be so?
Lightning isn't at all necessarily indicative of tornadic
activity--certainly tornadoes are spawned from t-storms, but I'm
pretty sure it's news to the folks in Norman (NOAA severe weather
office) there's predictive capability in the lightning...


We rarely have tornados but the idea of watching my spectrum analyzer
for lightning pulses sounds interesting. I put a scanner antenna on it
that receives 25 to 1300 MHz.

However the RF spectrum of lightning falls off far below Ch2, which
covers 54-60MHz:
http://www.stormwise.com/striking.htm
http://www.progettomem.it/appr_noise.php?id=5
When I was young I built a receiver and big loop antenna to listen to
sferics, tweeks and whistlers. Radiation from AC power lines drowned
out everything else unless I took it a few miles into the woods, which
is not a good place to be during a storm.

This is a commercial lightning indicator:
http://www.seaerospace.com/bfg/wx500pg.pdf

jsw

dpb wrote:

On 3/8/2013 7:01 PM, Michael A. Terrell wrote:
...

Tune to channel 13 and turn the brightness control down to the point
where the image is nearly--not completely--black. Then turn to channel
2. Lightning will register as horizontal streaks on the screen. When the
picture becomes bright enough to be seen, or when the screen glows with
an even light, there's a tornado within 20 miles, ...

What makes you think that's even remotely likely to be so? Lightning
isn't at all necessarily indicative of tornadic activity--certainly
tornadoes are spawned from t-storms, but I'm pretty sure it's news to
the folks in Norman (NOAA severe weather office) there's predictive
capability in the lightning...


I didn't write the quoted text.

"Richard" wrote in message
Tune to channel 13 and turn the brightness control down to the point
where the image is nearly--not completely--black. Then turn to
channel 2. Lightning will register as horizontal streaks on the
screen. When the picture becomes bright enough to be seen, or when
the screen glows with an even light, there's a tornado within 20
miles, and it's time to find Toto and head for the basement.


If that idea catches on someone could drive around with a milliwatt
transmitter broadcasting:


REPENT
THE END IS NEAR!

On Mar 7, 10:47*am, wrote:
There are millions of people who live in the Tornado belt. *I want to
buy a Tornado warning device for my home. The National Weather service
delights in waking me up in the middle of the night if Tornado
conditions occur in the neighboring State. I want to install a device
on the roof of my house that listens for the characteristic sound of a
Tornado approaching on the ground.

Think about this problem because the solution could make you rich.

Somebody apparently already has and invented something called "doppler
radar". "Doppler radar can tell when a thunderstorm has Tornado
Vortex Signature (TVS)" I doubt you could afford one, but you may be
able to make one of your own.

"While the NWS radars and some radars operated by television stations
have Doppler capability to show wind direction and speed, the images
are extremely complex and are much more difficult to understand than
reflectivity images. (Related: Doppler radar)" Hook echo's "... are
commonly found in a single thunderstorm, in which the reflectivity
image resembles a hook. When this occurs, the thunderstorm is
producing a circulation and possibly a tornado. The rain gets wrapped
around this circulation in the shape of a hook.

-- http://usatoday30.usatoday.com/weather/wearadar.htm

"Transition Zone" wrote in message
news:955542dd-0234-410f-a0ce-
-Somebody apparently already has and invented something called
"doppler
-radar". "Doppler radar can tell when a thunderstorm has Tornado
-Vortex Signature (TVS)" I doubt you could afford one, but you may be
-able to make one of your own.

In the 70's I built a low-powered Doppler radar for about $50; they
aren't very complicated. The diode detector's output is an audio tone
proportional to the speed of the target towards or away from you, so
the faster it moves the higher the pitch. Cop speed radars use the
principle. The ~200 MPH debris in a tornado would make it scream.
http://www.advancedreceiver.com/page31.html

It gave out a really strange Boioioingggg from the reflection off and
between the steel beams when driving under a bridge. It also triggered
every radar detector around and was fun to flash at passing speeders.

On 3/9/2013 1:45 PM, Jim Wilkins wrote:
"Transition wrote in message
news:955542dd-0234-410f-a0ce-
-Somebody apparently already has and invented something called
"doppler
-radar". "Doppler radar can tell when a thunderstorm has Tornado
-Vortex Signature (TVS)" I doubt you could afford one, but you may be
-able to make one of your own.

In the 70's I built a low-powered Doppler radar for about $50; they
aren't very complicated. The diode detector's output is an audio tone
proportional to the speed of the target towards or away from you, so
the faster it moves the higher the pitch. Cop speed radars use the
principle. The ~200 MPH debris in a tornado would make it scream.
http://www.advancedreceiver.com/page31.html

It gave out a really strange Boioioingggg from the reflection off and
between the steel beams when driving under a bridge. It also triggered
every radar detector around and was fun to flash at passing speeders.




Pics (or schematics), or it didn't happen.

Weather doppler is a bit tougher.
THE air mass is not a steel structure.
And it's coming at you and going away at the same time and pretty much
same speed (by comparison).

On Sat, 09 Mar 2013 17:07:25 -0600, Richard wrote:
On 3/9/2013 1:45 PM, Jim Wilkins wrote:
"Transition Zone" wrote ...
Somebody apparently already has and invented something called
"doppler-radar". "Doppler radar can tell when a thunderstorm has
Tornado-Vortex Signature (TVS)" I doubt you could afford one,
but you may be -able to make one of your own.

In the 70's I built a low-powered Doppler radar for about $50; they
aren't very complicated. The diode detector's output is an audio tone
proportional to the speed of the target towards or away from you, so
the faster it moves the higher the pitch. Cop speed radars use the
principle. The ~200 MPH debris in a tornado would make it scream.
http://www.advancedreceiver.com/page31.html

It gave out a really strange Boioioingggg from the reflection off and
between the steel beams when driving under a bridge. It also triggered
every radar detector around and was fun to flash at passing speeders.

Pics (or schematics), or it didn't happen.

http://www.dvice.com/archives/2012/07/make-your-own-d.php is an
example: "Make your own Doppler radar out of coffee cans". This one is
like a "radar gun" and as you note, "Weather doppler is a bit tougher".

Weather doppler is a bit tougher.
THE air mass is not a steel structure.
And it's coming at you and going away at the same time and pretty much
same speed (by comparison).


--
jiw

"James Waldby" wrote in message
...

http://www.dvice.com/archives/2012/07/make-your-own-d.php is an
example: "Make your own Doppler radar out of coffee cans". This one
is
like a "radar gun" and as you note, "Weather doppler is a bit
tougher".

Weather doppler is a bit tougher.
THE air mass is not a steel structure.
And it's coming at you and going away at the same time and pretty
much
same speed (by comparison).
jiw

If the NWS storm alert system used a digital, GPS-aware cellular radio
network like OnStar or ADS-B they could tag tornado warnings with the
projected track plus an estimate of uncertainty or DOP
http://en.wikipedia.org/wiki/Dilution_of_precision_(GPS)
so each receiver could respond only to nearby threats.

IOW the warning area could begin as a large circle when the tornado is
first detected, then converge to the area ahead of it as its path
becomes known. Al the receiver needs is a center point plus a radius
around it.

It's possible but hardly worth the effort for the current VHF FM
analog weather radios, though perhaps a good idea for a smart phone
app.
jsw