Electronics Forum / Electrical Engineering / March 2006

I have been having problems with a mobility scooter I purchased a while
ago. It's a "lightweight Squizz Scooter".
It worked fine for about 10 months, then suddenly, it started having
problems. It kept cutting out as it was going along, so that it came to

where would i be able to order ic samples for free? pl help me out.

in the context of binary, a logical AND could be defined as the
multiplication of bits
but is this definiton valid in other number systems,like base9 or
decimal systems?

Typical 110V, 15amp house/workshop, except...
I need to fit two three-way switches into a 2"x4" box, but I can't find
one anywhere. All I've seen is a "combo" switch that consists of one
3-way switch in tandem with a regular switch.

Over the years, I've kept a few ATX power supply from old computers.  Now,
I'm thinking about upgrading my computer and add more hard disks.  The
problem is the current power supply might not be able to support so many
hard disks running at the same time.  Instead of buying a new ...

--> I was wondering how a battery charger really works? Does it provide
the same amount of voltage and current to the battery that battery
provides?
--> how do I calculate the time it needs for the battery to be charged?

I need assistance with identifying the cause of a transformer core
overheating problem.  I am not an electrical engineer but I have 20
years of experience in transformer repair.
The unit in question is a 2500/3333 KVA GTE/Sylvania dry type

I'm an italian telecommunication engineer (recently graduated), and, after
a brief experience in the world of job and a lot of stories from my older
university buddies, I'm feeling that italian situation is not that good for
us. I mean, almost no one can find a job where he has to ...

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Dear group,
after verifying to myself (using pspice) that a balancing transformer with
high mutual inductance between both halves of the winding (without being a
particualarly high inductance, even) gives an incredible reduction on

How much amps can take a coil for a nema size 5 contactor. The coil is
125 vdc! I am reading 3 amps and the coil gets hot, but i have no
baterries, just a variac with a diode bridge to feed the coil!
Thanks in advance.

I am looking at the Weller soldering stations and was wondering if
someone could answer some questions for me.  First, other than the
higher wattage, why would I want a WD1000 over a WESD51?  Does any one
know the difference between the WESD51 and WESD51D?  They look like the

Dear member:
I have a technical question:  I have seen many electric showers
installed in houses, even without grounding system.  Why, in an
electric shower, doesn't exist any risk of electric shock to users,

In USA supply is in 60 Hz whereas in other country it is 50 Hz why this
is so?

I am trying to learn the basics of induction motors.  So far I have
learned that there are  single phase, three phase etc.  Also, a lot has
to do with load and power.  Just what exactly does load mean and how do
I calculate total power if I have 3 motors with 2hp, 20hp and 10hp