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78 October 2009
Radio Read Interrogation Device
My city has installed an Invensys
water meter with a sensus radio read
transceiver. I would like to build/buy an
interrogator device so I can transfer
daily/hourly water use to my computer
in order to monitor water consumption.
Is this possible without buying an
#10091 Burkhard Lehmann
I need a parts list and schematic on
how to create flashing lights on small
scale emergency vehicles to be used
on a slot car racing layout.
#10092 Bob Farrell
I want to use the flip style package
(like a "flip-style" cell phone) for an electronics project. It’s sometimes referred
to as a book-style package solution,
where there are electronic functions
integrated on both sides of the hinge. I
am having trouble identifying the best
interconnect products to use for the
hinged interface. Can I develop a prototype on a (reasonably) low budget?
#10093 William Quillen
High Current Heater
I’m trying to raise the temperature
of a tungsten heater from room temperature ( 25 C to 900 C) with a ramp of
one hour. My filament is very small and
hence has a small resistance — 0.08
ohm at 1,200 C. At room temperature,
its resistence is 12-13 times smaller.
Powering the filament is a huge 50 amp
variable transformer. I am also using a
temperature controller (Omega cni32).
Most power supplies I have seen use a
phase angle firing SCR with soft start
and current limiting capabilities.
#10094 Hugo Leon
Remote Temperature Logger
I want to monitor the temperature
of my attic during the summer months.
Ideally, I'd also like to know how
long the roof fan runs for, but it's hard
wired and probably more difficult. I
considered doing this by using a sensor
to detect the sunlight. As the fan blades
spin, the device would count the
turning of the fan blades.
I'll settle for a simple temperature
detector that can send the data to my
PC and some program that will graph
the temperature over time.
The attic isn't used so a long
averaging time constant isn't required
because nobody is walking by disturbing
the surrounding air.
I considered a simple thermistor
with a 5-10 second RC circuit going
into a Linx device that will transmit the
data back to the PC. I would also need