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television sent out a distress signal

Sunday, October 17, 2004
Last modified Saturday, October 16, 2004 10:40 PM PDT

Ryan Gardner/Gazette-Times
Chris van Rossman's television sent out a distress signal that was
picked up by an orbiting satellite.

Mystery signal traced to TV

By Jennifer Nitson
Corvallis Gazette-Times

CORVALLIS — When Chris van Rossman moved into his downtown apartment
about a year ago, his parents bought him a new 20-inch color TV with
all the bells and whistles.

The flat-screen Toshiba came with its own set of stereo speakers, a
181-channel tuner, built-in VCR, DVD and CD players, a V-chip for
parental control over content and, of course, a remote control.

Van Rossman, unfortunately, does not have cable and can only get four
channels in his apartment. He mostly watches Oregon Public
Broadcasting, which comes in clearest, and he's acquired a taste for
OPB children's programming.

Maybe the television suffered an identity crisis. Maybe it aspired to
higher things.

Whatever the reason, van Rossman's TV set sent out a cry for help. It
began emitting the international distress signal on the night of Oct.
2.

The 121.5 MHz frequency signal was picked up by an orbiting search and
rescue satellite, which informed the Air Force Rescue Coordination
Center at Langley Air Force Base in Virginia.

Such signals usually come from electronic locator transponders that
help search and rescue workers find overturned boats or crashed
airplanes. It is said that more than 90 percent of ELT signals are
false alarms, but each and every one is checked out.

Langley got on the horn to the Civil Air Patrol, an all-volunteer
auxiliary to the Air Force, and the CAP got ahold of Benton County
Search and Rescue Deputy Mike Bamberger for assistance in locating the
source of the signal.

"My initial thought was, ‘Oh, it's the airport again,'" Bamberger
said. "We've had the signals from the airport go up the Willamette
River all the way through Albany and into Lebanon."

The radio-wave signals can bounce off metal structures and rocky
hillsides. From time to time Bamberger is dispatched to the airport to
locate a transponder in a plane that has been bumped by a mechanic or
set off by a rough landing.

But this case was different.

Armed with small receiving devices, Bamberger and a group of Civil Air
Patrol volunteers determined the distress signal was coming from an
apartment building on the corner of Fourth Street and Jackson Avenue,
narrowing the possible sources down to a couple of upstairs units.

On the morning of Oct. 3, van Rossman opened his front door to find
CAP personnel in Air Force uniforms, a Corvallis police officer and a
Benton County Search and Rescue deputy looking at him expectantly. To
his credit, he did not stress out.

"I have a pretty spotless record, so I wasn't overly concerned — just
a little confused," van Rossman said. "The police officer asked if I
was a pilot or had a boat or anything. I said no, and they moved on."

After checking in with van Rossman, the group continued the search.

"We narrowed it down to a spot on the wall in the hallway," Bamberger
said. "Whatever was behind that spot is what it was."

They knocked on van Rossman's door again, and the signal abruptly
stopped.

"When he answered the door he turned off the TV, and the guy in the
hall said, ‘It just stopped,'" Bamberger recalled.

An inspection of the television confirmed it was the source of the
signal. "Their equipment was just bouncing everywhere as they turned
it on and off," van Rossman said.

Van Rossman was instructed to keep his TV turned off or face fines of
up to $10,000 per day for emitting a false distress signal.

He's not taking any chances. He's keeping the television unplugged
just in case he forgets one morning, groggy with sleep.

Unfortunately, the warranty on the TV had run out 16 days before it
started freaking out. It had already tried to escape the van Rossman
household by refusing to play DVDs a few months back, but that didn't
bother van Rossman. He has a DVD player on his computer, and besides,
he mostly just likes to watch OPB — especially "Arthur."

"I find other stuff to do," van Rossman said. "It's not too important.
It's changed my morning routine."

Alas, "Arthur" will have to wait.

Not for too long, though. Maria Repole, director of public relations
at Toshiba, is going to get van Rossman a new TV.

"We have never experienced anything like this before at Toshiba,"
Repole said. "We really value customer satisfaction, and we will
replace the television set free of charge."

Repole told Toshiba's technicians about the TV in distress, and
they'll be on the lookout in case it happens again, she said.

"They've never heard of that before," Repole said. "They don't really
have a technical explanation available. It's just very strange."

David Mandrell, squad leader for the CAP team that responded to the
TV's distress call, attempted an explanation.

"All electronic equipment creates a frequency called a tempest," he
said. "Sometimes these frequencies emit low-level signals that are
close to the 121.5 MHz signal."

Mandrell has heard of this sort of thing happening with customized
computer gear. Sometimes CAP equipment will pick up these signals, he
said, but they are usually weak enough to ignore.

"This was really strong," Mandrell said. "This was abnormally strong.
It kind of surprised us."

--------------------------------------------------------------------------------

Copyright © 2004 Democrat-Herald

Van Rossman was instructed to keep his TV turned off or face fines of
up to $10,000 per day for emitting a false distress signal.
---------------------------------------------------

and wide frequency range scanners are bound to have the local oscillator
to transmit on such a frequency if you set your scanner to a certain
frequency to listen to.

But it's always the consumers who get into trouble and never the
manufacturers who get into trouble.

wrote in message
...
Van Rossman was instructed to keep his TV turned off or face fines of
up to $10,000 per day for emitting a false distress signal.
---------------------------------------------------

and wide frequency range scanners are bound to have the local oscillator
to transmit on such a frequency if you set your scanner to a certain
frequency to listen to.

True, and some of those LO's can be quite strong, regardless of supposedly
being regulated by Part 15 rules. I had a Bearcat BC-250 scanner back when
they were new that if I set it just to the right frequency, I could open a
ham repeater three miles away with the LO.

postal97321 wrote:

Sunday, October 17, 2004
Last modified Saturday, October 16, 2004 10:40 PM PDT

Ryan Gardner/Gazette-Times
Chris van Rossman's television sent out a distress signal that was
picked up by an orbiting satellite.

"All electronic equipment creates a frequency called a tempest," he
said. "Sometimes these frequencies emit low-level signals that are
close to the 121.5 MHz signal."

Mandrell has heard of this sort of thing happening with customized
computer gear. Sometimes CAP equipment will pick up these signals, he
said, but they are usually weak enough to ignore.

What exactly are these search and rescue people listening for? Wouldn't
an emergency beacon be sending some kind of intelligent signal, like SOS
in morse code, or some kind of RTTY? At the very least, a certain kind
of modulated tone. It seems to me that if they're going to chase after
every spurious signal that pops up on 121.5, no matter what it sounds
like, that's a recipe for failure. No wonder 90% of their hits are
false positives.

Tony Calguire wrote:
What exactly are these search and rescue people listening for? Wouldn't
an emergency beacon be sending some kind of intelligent signal, like SOS
in morse code, or some kind of RTTY? At the very least, a certain kind
of modulated tone. It seems to me that if they're going to chase after
every spurious signal that pops up on 121.5, no matter what it sounds
like, that's a recipe for failure. No wonder 90% of their hits are
false positives.

If you find yourself in a heap of burning airplane parts in some valley
one day, I really hope they're still looking for weak signals on that
frequency if your ELT gets damaged. You'll hope so, too.

--
Most dying mothers say, "I love you, son," or "Take care of your sister."
Why were the last words of Kerry's mother a lecture on integrity?

I noticed the TV owner was using an antenna, instead of cable. I imagine
that the TV antenna (rabbit-ears dipole?) helped to transmit the signal in
a manner that could be received by the the satellite. If it had just been
plugged into cable, it might not have been strong enough. I bet more of
these sets get this problem occasionally, just it never becomes an issue.

Conan Ford wrote in message 23.159...
I noticed the TV owner was using an antenna, instead of cable. I imagine
that the TV antenna (rabbit-ears dipole?) helped to transmit the signal in
a manner that could be received by the the satellite. If it had just been
plugged into cable, it might not have been strong enough. I bet more of
these sets get this problem occasionally, just it never becomes an issue.

The TV in the common area, in the building I live in, also throws of a
spurious signal on 121.500. It is an old "Citizen" brand TV,
connected to a "Rogers" cable coverter.
Fred Burgess

In article ,
Tony Calguire wrote:
postal97321 wrote:
....
Ryan Gardner/Gazette-Times
Chris van Rossman's television sent out a distress signal that was
picked up by an orbiting satellite.
....

What exactly are these search and rescue people listening for? Wouldn't
an emergency beacon be sending some kind of intelligent signal, like SOS
in morse code, or some kind of RTTY? At the very least, a certain kind
of modulated tone. It seems to me that if they're going to chase after
every spurious signal that pops up on 121.5, no matter what it sounds
like, that's a recipe for failure. No wonder 90% of their hits are
false positives.

It's some sort of a warble tone on a carrier.

They use a transponder on polar orbiting satellites (weather and earth
sensing ones, usually) that allows the ground stations to do a doppler
measurement. Sort of the reverse of the Transit satellite navigation
system, where the timing and frequency shift of the signal allowed the
ground station to determine its position to a fraction of the meter.
The Transit system used atomic clocks, so the SARSAT accuracy would be
lower. But accurate enough to get the search and rescue close enough to
use portable direction finding gear.

Mark Zenier Washington State resident

On Mon, 18 Oct 2004 00:57:07 -0500, clifto wrote:

Tony Calguire wrote:
What exactly are these search and rescue people listening for? Wouldn't
an emergency beacon be sending some kind of intelligent signal, like SOS
in morse code, or some kind of RTTY? At the very least, a certain kind
of modulated tone. It seems to me that if they're going to chase after
every spurious signal that pops up on 121.5, no matter what it sounds
like, that's a recipe for failure. No wonder 90% of their hits are
false positives.

If you find yourself in a heap of burning airplane parts in some valley
one day, I really hope they're still looking for weak signals on that
frequency if your ELT gets damaged. You'll hope so, too.
that's one of the reasons 121.5 Mhz ELT's are going away. They are
simply beacons, and any signal on 121.5 can be an ELT,maximum power
out is 100mw. The EPIRB and PLB use a digitally encoded 406Mhz signal
with a 5 watt output, and contains the beacon ID, and can also carry a
GPS determined position as a data payload. In addition all 406Mhz
units must be registered, because 121.5 and 243 Mhz units are not
encoded, they are not registered.

matt weber wrote in message . ..
On Mon, 18 Oct 2004 00:57:07 -0500, clifto wrote:

Tony Calguire wrote:
What exactly are these search and rescue people listening for? Wouldn't
an emergency beacon be sending some kind of intelligent signal, like SOS
in morse code, or some kind of RTTY? At the very least, a certain kind
of modulated tone. It seems to me that if they're going to chase after
every spurious signal that pops up on 121.5, no matter what it sounds
like, that's a recipe for failure. No wonder 90% of their hits are
false positives.

If you find yourself in a heap of burning airplane parts in some valley
one day, I really hope they're still looking for weak signals on that
frequency if your ELT gets damaged. You'll hope so, too.
that's one of the reasons 121.5 Mhz ELT's are going away. They are
simply beacons, and any signal on 121.5 can be an ELT,maximum power
out is 100mw. The EPIRB and PLB use a digitally encoded 406Mhz signal
with a 5 watt output, and contains the beacon ID, and can also carry a
GPS determined position as a data payload. In addition all 406Mhz
units must be registered, because 121.5 and 243 Mhz units are not
encoded, they are not registered.

And these REGISTERED units have the contactee's name and home phone
number. Within literally minutes, say like the Coast Guard, is calling
that person's home phone number to find out what the deal is.
Unfortunately, sometimes all they can get is the spouse of the
registered owner, and he or she don't have the faintest idea. All they
know is their husband or daddy does fly on the company plane once in a
while and he's away right now. But in the long run, it DOES save a lot
of needless searches for errant transmissions. And a heavy fine to
boot if set off fecklessly with no confirmation. 15 to 20 thousand
dollars per occurrance, if I remember correctly. If you do set one
off, especially an aircraft one, call 1-800-WXBRIEF and that number
will rotate your call to your nearest Flight Service Station to cancel
the inquieries and explain your situation. The days of CAP members
tramping all over the neighborhood all day searching for an accidental
trip are hopefully over.

And a heavy fine to boot if set off fecklessly with no confirmation.

Now, that's a funny thought -- a distress signal set off fecklessly.

"Brian Running" wrote in message . com...
And a heavy fine to boot if set off fecklessly with no confirmation.

Now, that's a funny thought -- a distress signal set off fecklessly.

Ha ha! Well maybe. I wasn't trying to be pretentious. I was simply
typing fast and for the life of me I couldn't think of an appropriate
word to use such as, 'carelessly' or better yet, 'irresponsibly'. I
find that being at a loss for words happening more often the older I
get!

"clifto" wrote in message
...
[snip]
--
So those 380 tons of missing explosives were moved by Saddam before all
those expert inspectors noticed, eh?

No wonder twelve years of inspections found NOTHING.

What dream did you dream that in? LOL

If you listened to the story carefully, they were STILL there, undistured,
bunkers still
sealed, when the inspectors checked before they left. They were
looted/stolen/moved
between then and when the US troops occupied the compound a few weeks later.

Maybe you're auditioning for a position with the Bush spin team? ;-)

Tom

clifto wrote:
generally have no significant signatures either. TRF radios lack
oscillators, hence have no significant EMI/RFI signature.

The only TRF radio I ever owned certainly had an oscillator. Matter of
fact, it had two, one in the mixer stage and one BFO.

There seem to be two different definitions of "TRF" floating around.

Definition #1:
A TRF radio has one or more tuned RF amplifier stages before the mixer.

Definition #2:
A TRF radio has no mixer. There are one or more tuned RF amplifier
stages, then a detector, then one or more audio amplifier stages.

The former would be less likely to radiate spurious local-oscillator
signals; they would have a harder time leaking through the RF amplifiers
backwards. It could however happen.

The latter is how many (most) radios were built before Armstrong
invented the superhetrodyne circuit. (before there was such a thing as
a mixer) No local oscillator exists to be radiated. On the other hand,
it's difficult to keep a set like this stable and to keep the tuned
circuits tracking on the same frequency.
--
Doug Smith W9WI
Pleasant View (Nashville), TN EM66
http://www.w9wi.com

Doug Smith W9WI wrote:
clifto wrote:
The only TRF radio I ever owned certainly had an oscillator. Matter of
fact, it had two, one in the mixer stage and one BFO.

There seem to be two different definitions of "TRF" floating around.

Definition #1:
A TRF radio has one or more tuned RF amplifier stages before the mixer.

Definition #2:
A TRF radio has no mixer. There are one or more tuned RF amplifier
stages, then a detector, then one or more audio amplifier stages.

Which makes a TRF radio sort of like a radio with a volume control, in
that neither volume control nor TRF says much about any other aspect of
the radio's design. :)

--
So those 380 tons of missing explosives were moved by Saddam before all
those expert inspectors noticed, eh?

No wonder twelve years of inspections found NOTHING.

On Wed, 27 Oct 2004 00:11:55 -0500, clifto wrote:

matt weber wrote:
Not all devices have such a signature in the first place. The US Navy
is quite fond of TRF radios. Devices that have no oscillators
generally have no significant signatures either. TRF radios lack
oscillators, hence have no significant EMI/RFI signature.

The only TRF radio I ever owned certainly had an oscillator. Matter of
fact, it had two, one in the mixer stage and one BFO.

Except that by definition, a TRF cannot have a mixer stage, it has no
IF stages. that why it is called a TRF.

matt weber wrote:
On Wed, 27 Oct 2004 00:11:55 -0500, clifto wrote:
matt weber wrote:
Not all devices have such a signature in the first place. The US Navy
is quite fond of TRF radios. Devices that have no oscillators
generally have no significant signatures either. TRF radios lack
oscillators, hence have no significant EMI/RFI signature.

The only TRF radio I ever owned certainly had an oscillator. Matter of
fact, it had two, one in the mixer stage and one BFO.

Except that by definition, a TRF cannot have a mixer stage, it has no
IF stages. that why it is called a TRF.

I'll take your word for it, but when I learned the term it only seemed
to mean a radio with a tuned RF stage, implying nothing more about the
radio. Kinda had the sense of "air-conditioned car".

--
So those 380 tons of missing explosives were moved by Saddam before all
those expert inspectors noticed, eh?

No wonder twelve years of inspections found NOTHING.