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110 May 2008
I'd like to use a white LED to light
up a wall-mounted keepsake box (like a
picture frame, but thicker). It should
light with a pushbutton and turn itself
off after an hour or two and use as little
current as possible when off.
I have two questions about the
IBM Ideascan model 0275011 used on
the parallel port (printer port):
1. What is the wavelength of the
2. What are the control codes, e.g.,
light on/off, move, stop, speed, etc.
#5082 Paul Weijers
Lachine, QC Canada
Has anyone hacked a digital
camera and installed the sensor and
minimum circuits into an old film
camera like an old Nikon F or Leica M2
or M3? I've seen astrophotog guys hack
digital Canon EOS D30 and Rebel to
remove the IR filter for IR photography
... I don't know which electronics I can
safely clip out of the digital donor.
(There are film camera nuts out there
that would die to see this done.)
#5083 George Kase
I'm looking for an affordable (US)
PCB MFG who specializes in prototype
quantities (< 100) of COB (chip on
board) from DIE that I provide. I need a
company who can lead-attach the DIE
and epoxy-seal it, forming a COB PCB.
#5084 Charlie Van Dien
Port Saint Lucie, FL
[#3082 - March 2008]
Can someone explain how the
digital-to-analog TV converters will work?
Prior to February 2009, US
domestic over-the-air television stations
transmit an analog signal called NTSC
which has remained the same since
1953. After that date, television stations
will transmit a digital data stream over
the air and analog TV sets will require
a converter, which will be subsidized
to $40 by a coupon from the Federal
Inside the converter box, a tuner —
similar to the existing analog RF front
end of a TV set — will select channels
and pass the 44 MHz IF to an analog-to-digital converter. The resulting digital
data is decoded by an MPEG2-HD
circuit and stored in digital memory,
which is needed to reconstruct the
original image as the compressed data
arrives. The format of the data is
determined by the program source
material and can be any standard from
SDTV (Standard Definition TV formerly
known as NTSC) at 4: 3 aspect 525i60,