On Sun, 29 Mar 2009 01:44:49 GMT, William R. Walsh wrote:
Hello all...

I was cleaning up some stuff in the basement when I found a cardboard box
with a Newsweek address on it. Opening it revealed a small white-cased
device with an on-off pushbutton and a speaker. It uses 4 double-A
batteries. There are no other controls or indicators on it anywhere.

I first thought that it had to be some kind of a fixed-frequency radio,
probably something that was tuned to one AM station for promotional purposes
or maybe even a weather radio. But it doesn't seem to receive
anything--assuming it even works. With batteries in place, it would hum
(much like ground loop hum) and the sound would get louder near electrical
wiring. I never heard any sort of station or static.

Taking it apart revealed a very simple circuit board with a coil, power
switch, a few small transistors, some resistors and a few caps. It's really
very simple--too simple to be any kind of radio I'd know about. The one IC
on it is an STMicroelectronics TBA820M audio amplifier, with a date code of
early 1988. Running it while taken apart revealed a few things--let the
circuit board get near the battery compartment or wires, and the speaker
would go into feedback. The coil on the board was sensitive to touch or
metal tools--and produced a "tapping" sound in the speaker when touched. It
was not sensitve to other random objects on my workbench. I also found that
I could feed audio into one of the connections on the coil and hear it
clearly through the speaker.

A picture of the circuit board is he
http://greyghost.mooo.com/newsweek-radio.jpg (541x255, 47KB)

Probablty a Stud Finder -- locates the nails in the drywall hammered
into the stud.

Jonesy
--
Marvin L Jones | jonz | W3DHJ | linux
38.24N 104.55W | @ config.com | Jonesy | OS/2
* Killfiling google & XXXXbanter.com: jonz.net/ng.htm

Hello all...

I was cleaning up some stuff in the basement when I found a cardboard box
with a Newsweek address on it. Opening it revealed a small white-cased
device with an on-off pushbutton and a speaker. It uses 4 double-A
batteries. There are no other controls or indicators on it anywhere.

I first thought that it had to be some kind of a fixed-frequency radio,
probably something that was tuned to one AM station for promotional purposes
or maybe even a weather radio. But it doesn't seem to receive
anything--assuming it even works. With batteries in place, it would hum
(much like ground loop hum) and the sound would get louder near electrical
wiring. I never heard any sort of station or static.

Taking it apart revealed a very simple circuit board with a coil, power
switch, a few small transistors, some resistors and a few caps. It's really
very simple--too simple to be any kind of radio I'd know about. The one IC
on it is an STMicroelectronics TBA820M audio amplifier, with a date code of
early 1988. Running it while taken apart revealed a few things--let the
circuit board get near the battery compartment or wires, and the speaker
would go into feedback. The coil on the board was sensitive to touch or
metal tools--and produced a "tapping" sound in the speaker when touched. It
was not sensitve to other random objects on my workbench. I also found that
I could feed audio into one of the connections on the coil and hear it
clearly through the speaker.

A picture of the circuit board is he
http://greyghost.mooo.com/newsweek-radio.jpg (541x255, 47KB)

William

In article loAzl.35968$DP1.24027@attbi_s22,
"William R. Walsh"
m wrote:

Hello all...

I was cleaning up some stuff in the basement when I found a cardboard box
with a Newsweek address on it. Opening it revealed a small white-cased
device with an on-off pushbutton and a speaker. It uses 4 double-A
batteries. There are no other controls or indicators on it anywhere.

I first thought that it had to be some kind of a fixed-frequency radio,
probably something that was tuned to one AM station for promotional purposes
or maybe even a weather radio. But it doesn't seem to receive
anything--assuming it even works. With batteries in place, it would hum
(much like ground loop hum) and the sound would get louder near electrical
wiring. I never heard any sort of station or static.

Taking it apart revealed a very simple circuit board with a coil, power
switch, a few small transistors, some resistors and a few caps. It's really
very simple--too simple to be any kind of radio I'd know about. The one IC
on it is an STMicroelectronics TBA820M audio amplifier, with a date code of
early 1988. Running it while taken apart revealed a few things--let the
circuit board get near the battery compartment or wires, and the speaker
would go into feedback. The coil on the board was sensitive to touch or
metal tools--and produced a "tapping" sound in the speaker when touched. It
was not sensitve to other random objects on my workbench. I also found that
I could feed audio into one of the connections on the coil and hear it
clearly through the speaker.

A picture of the circuit board is he
http://greyghost.mooo.com/newsweek-radio.jpg (541x255, 47KB)

William

A wild guess: an inductively-coupled half speakerphone--set near a
(transformer-based) phone, it would pick up audio from the transformer
in the phone and let everybody else in the room hear--but obviously not
directly participate in--the conversation.

--
Andrew Erickson

"He is no fool who gives what he cannot keep to gain that which he cannot
lose." -- Jim Elliot

In article ,
Meat Plow wrote:

Something that traces phone wires or other electric wiring?

That's about what I would guess.

A friend of mine recently had to trace down a couple of short circuits
in some in-wall wiring... a house he partially built a couple of
decades ago, which passed electrical inspection and has since been
sitting empty and idle. He disconnected the mains, then rigged up an
audio oscillator and power amp and a current-limiting resistor, and
used the combination to put an audio tone into the wiring at the
breaker box between the two wires which were showing a shorted load.
He then used a home-made setup similar to what you're showing (a coil,
fed to an audio amplifier) to trace along the walls, using the audible
tone to figure out where the wires were running inside the drywall.

By noting where the tone suddenly disappeared, he was able to figure
out where the wires inside the Romex were shorted. In the first case,
it was due to a drywall screw that had bit into the Romex and shorted
hot to ground (the screwhead turned out to be within 1/16" of where he
marked the "lost the signal here" spot on the painted drywall). In
the second case, he lost the tone at an outlet/switch box, and found
that an overly-tight cable retaining clamp had caused "cold flow" in
the PVC insulation of the Romex and had punched a small pinhole
through to the hot wire.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

William R. Walsh wrote:

Hello all...

I was cleaning up some stuff in the basement when I found a cardboard
box with a Newsweek address on it. Opening it revealed a small
white-cased device with an on-off pushbutton and a speaker. It uses 4
double-A batteries. There are no other controls or indicators on it
anywhere.

I first thought that it had to be some kind of a fixed-frequency
radio, probably something that was tuned to one AM station for
promotional purposes or maybe even a weather radio. But it doesn't
seem to receive anything--assuming it even works. With batteries in
place, it would hum (much like ground loop hum) and the sound would
get louder near electrical wiring. I never heard any sort of station
or static.

Taking it apart revealed a very simple circuit board with a coil,
power switch, a few small transistors, some resistors and a few caps.
It's really very simple--too simple to be any kind of radio I'd know
about. The one IC on it is an STMicroelectronics TBA820M audio
amplifier, with a date code of early 1988. Running it while taken
apart revealed a few things--let the circuit board get near the
battery compartment or wires, and the speaker would go into feedback.
The coil on the board was sensitive to touch or metal tools--and
produced a "tapping" sound in the speaker when touched. It was not
sensitve to other random objects on my workbench. I also found that I
could feed audio into one of the connections on the coil and hear it
clearly through the speaker.

A picture of the circuit board is he
http://greyghost.mooo.com/newsweek-radio.jpg (541x255, 47KB)

William

It could be an induction loop amplifier ! Used by people that are hard
of hearing !

--
Best Regards:
Baron.

Allodoxaphobia wrote:

On Sun, 29 Mar 2009 01:44:49 GMT, William R. Walsh wrote:
Hello all...

I was cleaning up some stuff in the basement when I found a cardboard box
with a Newsweek address on it. Opening it revealed a small white-cased
device with an on-off pushbutton and a speaker. It uses 4 double-A
batteries. There are no other controls or indicators on it anywhere.

I first thought that it had to be some kind of a fixed-frequency radio,
probably something that was tuned to one AM station for promotional purposes
or maybe even a weather radio. But it doesn't seem to receive
anything--assuming it even works. With batteries in place, it would hum
(much like ground loop hum) and the sound would get louder near electrical
wiring. I never heard any sort of station or static.

Taking it apart revealed a very simple circuit board with a coil, power
switch, a few small transistors, some resistors and a few caps. It's really
very simple--too simple to be any kind of radio I'd know about. The one IC
on it is an STMicroelectronics TBA820M audio amplifier, with a date code of
early 1988. Running it while taken apart revealed a few things--let the
circuit board get near the battery compartment or wires, and the speaker
would go into feedback. The coil on the board was sensitive to touch or
metal tools--and produced a "tapping" sound in the speaker when touched. It
was not sensitve to other random objects on my workbench. I also found that
I could feed audio into one of the connections on the coil and hear it
clearly through the speaker.

A picture of the circuit board is he
http://greyghost.mooo.com/newsweek-radio.jpg (541x255, 47KB)

Probablty a Stud Finder -- locates the nails in the drywall hammered
into the stud.

And finds where power cables are.

Graham

Allodoxaphobia writes:

On Sun, 29 Mar 2009 01:44:49 GMT, William R. Walsh wrote:
Hello all...

I was cleaning up some stuff in the basement when I found a cardboard box
with a Newsweek address on it. Opening it revealed a small white-cased
device with an on-off pushbutton and a speaker. It uses 4 double-A
batteries. There are no other controls or indicators on it anywhere.

I first thought that it had to be some kind of a fixed-frequency radio,
probably something that was tuned to one AM station for promotional purposes
or maybe even a weather radio. But it doesn't seem to receive
anything--assuming it even works. With batteries in place, it would hum
(much like ground loop hum) and the sound would get louder near electrical
wiring. I never heard any sort of station or static.

Taking it apart revealed a very simple circuit board with a coil, power
switch, a few small transistors, some resistors and a few caps. It's really
very simple--too simple to be any kind of radio I'd know about. The one IC
on it is an STMicroelectronics TBA820M audio amplifier, with a date code of
early 1988. Running it while taken apart revealed a few things--let the
circuit board get near the battery compartment or wires, and the speaker
would go into feedback. The coil on the board was sensitive to touch or
metal tools--and produced a "tapping" sound in the speaker when touched. It
was not sensitve to other random objects on my workbench. I also found that
I could feed audio into one of the connections on the coil and hear it
clearly through the speaker.

A picture of the circuit board is he
http://greyghost.mooo.com/newsweek-radio.jpg (541x255, 47KB)

Probablty a Stud Finder -- locates the nails in the drywall hammered
into the stud.

I have one of these things. The circuit board is identical to the
one in the pic.

At first, I did think it was some sort of telephone amplifier.

But now I'm inclined toward the stud or wiring finder type of application.

This is a small embossed arrow next to the on/off switch that lines
up with the coil.

Mine buzzes to some extent all the time, but is sensitive to ferrous
and/or magnetized objects near the coil. It squeels in various ways
depending on size, orientation, magnet strength, etc.

--
sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.

Allodoxaphobia writes:

On Sun, 29 Mar 2009 01:44:49 GMT, William R. Walsh wrote:
Hello all...

I was cleaning up some stuff in the basement when I found a cardboard box
with a Newsweek address on it. Opening it revealed a small white-cased
device with an on-off pushbutton and a speaker. It uses 4 double-A
batteries. There are no other controls or indicators on it anywhere.

I first thought that it had to be some kind of a fixed-frequency radio,
probably something that was tuned to one AM station for promotional purposes
or maybe even a weather radio. But it doesn't seem to receive
anything--assuming it even works. With batteries in place, it would hum
(much like ground loop hum) and the sound would get louder near electrical
wiring. I never heard any sort of station or static.

Taking it apart revealed a very simple circuit board with a coil, power
switch, a few small transistors, some resistors and a few caps. It's really
very simple--too simple to be any kind of radio I'd know about. The one IC
on it is an STMicroelectronics TBA820M audio amplifier, with a date code of
early 1988. Running it while taken apart revealed a few things--let the
circuit board get near the battery compartment or wires, and the speaker
would go into feedback. The coil on the board was sensitive to touch or
metal tools--and produced a "tapping" sound in the speaker when touched. It
was not sensitve to other random objects on my workbench. I also found that
I could feed audio into one of the connections on the coil and hear it
clearly through the speaker.

A picture of the circuit board is he
http://greyghost.mooo.com/newsweek-radio.jpg (541x255, 47KB)

Probablty a Stud Finder -- locates the nails in the drywall hammered
into the stud.

Well, that's what I had concluded (see my other posting). But now,
I'm leaning back toward the amplified telephone idea.

I placed it near one headphone from a Walkman and it did an excellent
job of amplifying it with the Waliman set at very low volume and providing
a fairly decent, if low fidelity, output from its loudspeaker. If even
worked 3 inches from a cell phone!

So, perhaps it's a multiuse device.

--
sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.

On Mar 29, 1:27*pm, (Samuel M. Goldwasser) wrote:
Allodoxaphobia writes:
On Sun, 29 Mar 2009 01:44:49 GMT, William R. Walsh wrote:
Hello all...

I was cleaning up some stuff in the basement when I found a cardboard box
with a Newsweek address on it. Opening it revealed a small white-cased
device with an on-off pushbutton and a speaker. It uses 4 double-A
batteries. There are no other controls or indicators on it anywhere.

I first thought that it had to be some kind of a fixed-frequency radio,
probably something that was tuned to one AM station for promotional purposes
or maybe even a weather radio. But it doesn't seem to receive
anything--assuming it even works. With batteries in place, it would hum
(much like ground loop hum) and the sound would get louder near electrical
wiring. I never heard any sort of station or static.

Taking it apart revealed a very simple circuit board with a coil, power
switch, a few small transistors, some resistors and a few caps. It's really
very simple--too simple to be any kind of radio I'd know about. The one IC
on it is an STMicroelectronics TBA820M audio amplifier, with a date code of
early 1988. Running it while taken apart revealed a few things--let the
circuit board get near the battery compartment or wires, and the speaker
would go into feedback. The coil on the board was sensitive to touch or
metal tools--and produced a "tapping" sound in the speaker when touched. It
was not sensitve to other random objects on my workbench. I also found that
I could feed audio into one of the connections on the coil and hear it
clearly through the speaker.

A picture of the circuit board is he
http://greyghost.mooo.com/newsweek-radio.jpg(541x255, 47KB)

Probablty a Stud Finder -- locates the nails in the drywall hammered
into the stud.

Well, that's what I had concluded (see my other posting). *But now,
I'm leaning back toward the amplified telephone idea.

I placed it near one headphone from a Walkman and it did an excellent
job of amplifying it with the Waliman set at very low volume and providing
a fairly decent, if low fidelity, output from its loudspeaker. *If even
worked 3 inches from a cell phone!

So, perhaps it's a multiuse device.

--
* * sam | Sci.Electronics.Repair FAQ:http://www.repairfaq.org/
*Repair | Main Table of Contents:http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ:http://www.repairfaq.org/sam/lasersam.htm
* * * * | Mirror Sites:http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. *Or, you can contact me via the Feedback Form in the FAQs..- Hide quoted text -

- Show quoted text -

Half of a baby minitor???

The original poster wrote
I placed it near one headphone from a Walkman and it did an excellent
job of amplifying it with the Waliman set at very low volume

Waliman excellent typo

Ron