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92 December 2008
Solar Battery Charger
I'm looking for a circuit for a micro-controller based solar battery charger
that can charge a group of four or eight
NiMH rechargeable AA batteries.
#12081 John Weygandt
PV vs. EMR
Since solar panels are inherently a
diode, would they survive the electromagnetic burst of an EMR weapon?
#12082 Larry Rheaume
I recently replaced my SMPS as it
was not working. I know the basics
about electronics and would like to try
to repair it myself (hard disc is not
reading). Can someone provide me
some information to troubleshoot and
repair my unit, if it is possible?
Variable Brightness Of LEDs
I have two sets of LEDs; eight LEDs
in each set. The sets need to turn on
alternately. However, I would like the
brightness to turn on gradually, then
fade out. Then, the second would turn
on and off in the same manner.
#12084 Arsen Dedic
Palm Springs, CA
I am looking for a timer circuit to
turn on and provide a source of
standard 120 VAC house power for a
cycle/duration of 24 hours, once every
set number of days (e.g., every 2nd day,
or every 3rd day, up to every 12th day).
The start and stop times would be at
the same hour of day.
For a cycle every third day:
Monday 13:00 hours ON
Tuesday 13:00 hours OFF
Thursday 13:00 hours ON
Friday 13:00 hours OFF
Sunday 13:00 hours ON
Monday 13:00 hours OFF
#12085 Ron Sharpe
Regina, SK Canada
Power Tool Batteries
Does anyone have information on
how to recell/rebuild power tool
batteries? Procedures and suppliers of
equipment needed to do it properly?
#12086 Will Vazquez
Forest City, NC
Can I modify a webcam to connect
to the RCA connectors on a TV?
#12087 Ken Hilke
New Wilmington, PA
How can you differentiate a bad
transistor from a good one?