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102 September 2006
I have heard that florescent lights
can be dimmed. The circuit is a
constant voltage generator (120V) and
a current controller that changes the
frequency to lower the light intensity.
Can someone supply such a circuit
that uses a variable frequency to
change the amount of current flowing?
The original ballast is still being
used in the circuit.
can get quite high for short on times?)
Here is an interesting tidbit for all
Nuts & Volts readers: In copper wire,
the rated current is 0.003 times the
circular mils. I saw this tidbit many
years ago and was too dense to grab its
significance but have since "got it" and
am wondering how many techs know it
and use it.
Robert C. Gibson
I want to use an accelerometer as
a motion sensor for a vehicle security
system. I just want to measure the
motion of the car.
Can someone please advise me on
which accelerometer type (capacitive,
temperature, etc.) is good for this
What are the advantages and
[#7064 - July 2006]
I purchased a GOLDSTAR DC
power supply model GP-305. There are
some LEDs, switches, and terminals that
I have not been able to figure out. Can
anyone tell me the function of these or
have a manual I might be able to copy?
The mystery elements are:
I have a question about heat dissipation vs. duty cycle. Power increases
proportional to current squared, and
linearly with respect to resistance. As
duty cycle varies, should I use the
square root of the on (off?) time to
calculate power? (Is this not analogous
to pulsed laser calculations where
energy is related to pulse duration and
1. A switch marked EXT/INT.
2. An LED marked C.C.
3. An LED marked C.V.
4. A external terminal strip with the
following contacts /C1/C2/+/EXT/
I have figured out GND.
The answers to Mr. Lang's questions are:
(1) This is for use with multiple units
and determines which one is the control unit.
(2) An LED marked C.C. When on,