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I have noticed that many of the
leads on capacitors and LEDs are
magnetic, as are the bodies of carbon-film resistors (but not the leads). Why is
that? Why not copper wire? Why is
there iron in a carbon film resistor?
#12071 Richard Gagnon
St. Paul, MN
I subscribe to cable phone with a
company that provides a bundle of
high-speed Internet access, television,
and phone service. A cable problem can
cause any one or all three to crash. My
primary concern is about the phone.
When it goes out, you won't know it
until you try to use it and get no dial
tone, or if someone tells you later that
they could not reach you. This has
caused me to miss important calls and
deliveries. Is there a circuit I could build
to monitor the cable phone line and alert
me (e.g., beep, buzz, blinking light, etc.)
when it goes down? My provider hasn't
a clue, and only apologizes for the
inconvenience over and over again.
#12072 T. Campbell
We have several computerized
machine tools that use serial ports to
upload and download their programs. It
is getting harder and harder to have our
minifile equipment repaired. I would
like to use a USB Flash to upload and
download programs through the serial
ports. It would be nice to have an LCD
readout to choose what program to
download from the Flash. Any help
with this project would be appreciated.
#12073 Brent Lamb
How do they generate that little
yellow first down marker during TV
football games? I know it's computer
generated, but it's been driving me
nuts as to how they do this! I can't
figure it out!
I need a device (preferably off-the-shelf) with two serial ports that can
capture a line of RS-232 data at 1200
or 2400 baud and then reorder the
information sequence (user definable)
and resend it on demand at 1200 or
2400 baud to a PC. The purpose is to
convert data from a PBX to a form the
PC can recognize; the program the PC
is running cannot be adjusted to read
the original data. I have looked at
various single board microcontrollers,
but most seem to be designed for 9600
baud, if they have a serial port.
#12075 Chris Snyder
I have a GPS unit made by Falcom
in Europe. It is hidden in my vehicle and
can be tracked on a private website for
December 2007 99