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Feedback section if space allows.
I would like to know if I can hook
up a Velleman K4003 amplifier to my
speakers directly to increase volume
and what does the circuit wiring entail.
#4071 Paul Kozlowski
I'm looking to build a battery
charger that can continuously charge a
battery under load — such as you
would find in an online UPS.
I'm not sure how this would differ
from a regular continuous maintenance
charger (i.e., a charger that supplies
a trickle charge, as well as periodic
higher power plate cleaning charges).
Any guidance would be appreciated.
#4072 Don Stahl
I am in the process of restoring an
older Chevrolet truck (1957) and would
like to put in high intensity discharge
(HID) headlights like some of the
high-end automobiles now have. I’m
looking for schematics, pointers, and
any other information on the
ballast/control circuit to drive them.
#4073 John Blankenagel
I've got an older computer (Plll at
500 MHz) and would like to add a
larger hard drive (250 GB @ ATA133 or
a 200 GB @ ATA100). I have been told
by some that the computer won't be
able to access the new drive's
entire capacity and won't be supported
by the micro-ATX motherboard
(GT440ZX). Presently, its 'primary' hard
drive is a 27.2GB U-DMA ATA- 66
which is now full (OS=WIN98SE). I
would like to copy all the files on it and
replace it with the larger drive.
If I install the 250 GB, will I be able
to access the entire capacity and
will it be supported by my existing
motherboard or will I have problems?
Also, I need a recommendation for
software which will allow me to copy
("mirror") and move all my files from
one drive to the other.
#4074 Michael Williams
I have a project that requires two
power amplifiers capable of driving
very low impedance AC motors. The
specs for the motors are 120 VAC at
4A. The motors will have the armature
removed as I am using only the field
assemblies in a magnetic amplifier. The
drive for the motors is two sine waves
and the output of the magnetic amplifier needs to be the sine wave sum of the
I will use a dual channel Direct
Digital Synthesizer from Nuts & Volts
Nov ’06, page 48. I will drive the
motors from near 0 Hz to about 50
kHz with the two inputs separated by
April 2007 93