Electronics Forum / Electronics / July 2006

I've got a plain 12V DC cooling fan that I took out of an old computer
that I'd like to reuse in another place. If i got an ordinary AC
adapter that's rated at 12V, I can wire the adapter to the fan without
any problems correct?

I am working on a project which tries to control illumination by
controling the electrical power consumed by an electrical lamp (a form
of dimmer). In a part of this project I need to discuss the relation
between the change in the illumination with what the visual system

It looks like Fairchild has dropped their line of colour LEDs.
What a shame.
I'm guessing its because of the many LED manufacturers out there that are
getting very competitive in price and quality.

like to do it as easily as ...

Does anyone have recommendations on USB oscilloscopes?  I'm hoping to stay
within a sub $500 price range, and would like the sample rate to allow at
least 100MSamples per channel with simultaneous 2 channel operation.  I
stumbled upon the Velleman PCSU1000, and it looked like a ...

Hi Group,
I'm looking for a relatively inexpensive way to transmit information
from one mains switching power supply to up to two other mains
switching power supplies a few feet away.  The data rate would be 1200

are there a difference between the two?
2n222
2n222a
can they be interchanged?

I'm looking at the data output from a Thomson RCT110S remote and the
code is not consistent for the same button press. Instead it seems to
alternate between codes for each press of that button. i.e, press "1"
and I get one code, press "1" again and I get a different code, press

PCBCAD17 is a great pcb layout package.
http://web.ukonline.co.uk/cresswellavenue/pcbcad17.htm

Vacuum tubes have largely been replaced by solid state devices. I know
that one can still purchase vacuum tubes and their sockets. What I'm
wondering is whether it is still possible to scavenge vacuum tubes from
things that people throw out and leave on the street for trash pickup.

Anyone know of a good source of switched pots?.
Looking for a 200K linear with 240V rated DPST
switch, ideally in 16mm size.
tia

Instead of manually adjusting a pot (voltage divider) to set the
desired current level through a servo loop (op-amp driving a FET), I'd
like to use a PIC controlling a DAC.  My problem is that even
rail-to-rail DACs only go down to a few millivolts, not true zero

I have a old P100 PC in the shed running DOS for a MP3 player, it's
equipped with a infrared sensor on the serial port for control by
remote.
What i'm wondering is it possible to splice another infrared sensor in

Hi.Trying to figure out how much my Dell desk-top uses but I couldn't
find a label.The cable modem and wireless router are warm 24/7 but
neither have a label either (I thought all electrical gadgets were
supposed to list values such as wattage,voltage and cycles).

Can someone please explain me how the coaxial cables work?
I'm looking for low loss BNC and SMA cables - 50 Ohm. Low loss is a
requirement, and as long as the  price is not $1/ft for 500ft, any
reasonable price is ok. Most of my applications are <200MHz.