I have an RV and I installed a
homemade electronic rear-view
mirror. I already had a 5” monitor and
connected it to a $39.00 CMOS black-and-white camera with 0.1 lux light
sensitivity. It works fine, but the image
is opposite from a mirror view when
viewed on the monitor. Isolved the
problem by pointing the camera
vertically into a mirror positioned at
45 degrees to the rear.
There are cameras with mirror
switching capabilities, but I’ve been
unable to locate one with 0.1 lux or
better sensitivity. I would like to know
about modifying an existing unit or if
reversing the function is built into an
LSI chip where I can’t get to it? A
functional diagram or schematic of a
camera would be helpful.
checksum error. When I plot a
drawing, it plots to one side and only
half of the drawing is on the page. HP
does not support this plotter any
more and I am having trouble
acquiring information on how to
troubleshoot. Where should I start?
#1053 Alex Malachowski
I am looking for a simple on/off
switch that can be triggered by
electrodes placed on the skin. It
needs to have a sensitivity
adjustment. I would also like to have it
opto-isolated for safety. Any
suggestions or places I can look?
#1052 Chris Tauscher
Anyone know of an after-market
lens to convert a common PC board
camera into a microscope with a
magnification between 60 and 150X?
#1054 Joe R.
I have acquired an HP 7580b
plotter that is mechanically sound.
When I turn it on, E02 is displayed
after a self-test. The operator manual
says it’s a microprocessor error/ROM
This is a READER-TO-READER Column. All
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I recently purchased a
communications test set for aligning
my ham radio related equipment. The
output generator's frequency is set
using thumbwheel switches. Although
I have had no trouble aligning
receivers with this piece of test
equipment, I got quite a surprise
when I attached three frequency
counters to the output. The readings
go wild, but — when I connect them to
older signal generators — the
responses are as expected. After
hooking the test set to my
oscilloscope, I saw the reason. The
signal generator is synthesized, not a
pure sign wave, and is chock full of
How, if at all, can I filter the
output sufficiently so a frequency
counter can be properly used? A
series of low pass filters lined up to be
switched in and out up to 1 GHz
seems a little far fetched.
#1055 John Ciperano K4EBC
NUTS & VOLTS
I’d like to use X10 cameras and
receivers — such as those sold by
www.x10.com — to beef up the
security of my home, inside and out.
The problem is that the units do
not secure their transmissions, which
leaves me vulnerable to outsiders
seeing inside my home, knowing
where things are, and whether or not
someone is at home. I’ve contacted
the resellers and they confirmed they
have no security.