Low Power IR Remote
I would like to make an IR remote
control to be used in nursing homes to
activate alarm equipment. Specifications
are: Receiver: nine volt, VERY LOW
power consumption; Transmitter:
handheld, battery powered, three volt
(lithium?), 2-5 meter range.
#6131 Claes Kamborn
must be able to hold the throttle
position for as long as the driver has
his foot on the gas pedal in any
position, and then return to the zero
position when the foot pedal is
released (return to the zero position).
Can someone help me accomplish
deteriorate over time to become
unreliable? Any advice out there?
#6135 Clint Stevens
Cell Phone Battery Cable
How can I make a cable so that I
could use a nine volt battery for my
cell phone? Would a large six volt
lantern battery work? Are there any
#6136 George Powelson
What’s the best way to cut a one
inch hole in a metal or plastic project
box? What about a square hole?
#6132 George Powelson
Drive By Wire
I want to build a 'drive by wire' system for a project that I have been
working on. I have enough electronics
knowledge that I feel I could build the
circuit by hand if I could get help on
the circuit diagram and parts needed.
I want to operate the throttle on a
14 HP engine via a servo with the gas
pedal hooked to a potentiometer, so
that when the 'gas' pedal is pushed, it
will open the throttle on the engine
and vice versa (close when 'gas' pedal
is released). The servo would need to
return to the same position as the
The circuit needs to run on a 10-
15 volt DC automotive voltage, and
be turned on and off with the ignition
switch. This would have to be bullet
proof because of the vibration caused
by the engine and terrain. The servo
Camcorder To Security Cam
I have many old MiniDV or Hi- 8
camcorders that still work very well as
far as the camera and monitor, not so
much for the recorder portion.
Has anyone thought of re-purpos-ing these to just use the camera
portion for a security/process monitor
camera? Some old camcorders have
superb resolution, a very low lux rating
for color, and great remote control
functions for focus, iris, and zoom. I
would need to disable the time-out
function for the recorder, which saves
the heads if not running for a while by
shutting down. Saves a lot over getting
a PTZ camera — if you need the P & T,
a small servo could do that function.
Anyone tried this? Please post
Excerpted from #7121
Modify Scott 340A Tube Receiver
I live very close to a huge water
tank that affects stereo reception. I
would like to connect a scope to
measure FM multipath distortion. Does
anyone know exactly how to do this?
You need an X-Y oscilloscope —
preferably with response down to DC.
Connect the horizontal X input to the
output from the audio detector (still
monophonic, not yet demultiplexed)
and connect the vertical Y input to the
AGC (automatic gain control) signal.
Since money for hobbies is hard
to come by these days, is it worth trying to salvage parts from old electronic equipment to build new projects?
What kind of equipment has the most
usable parts — old TVs, computers,
stereos? How far do component values
Follow-up To #7121
I switched my tube system to
separate units now using a Scott 350B.
I need to check multipath distortion as
in Tech Forum #7121, but wonder
what bandwidth I need for a scope.
I assume 100 MHz, but would a lower
bandwidth (less costly) scope work
okay? Would I hook it up as noted in
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78 June 2013
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