Electronics Forum / Basics / March 2005

I have been messing with CircuiMaker and doing "spice simulations"
I have also been reading from these different sites:
http://www.kpsec.freeuk.com/ohmslaw.htm
http://www.play-hookey.com/digital/ripple_counter.html

Just a question: Is ferrite bead actually an inductor? Or a filter?
Thnaks!

Does anyone have schematic for Output that is regulated with voltage (small
up to 2 V) and
otput is 0 - 2 Amps according to the input voltage?
Mickey

Hi - I remember hearing that some DC power supplies cannot be connected in
series, while others can. Can anybody tell me what
features/specifications/etc. to look for in a power supply that can be
connected in series with other power supplies? Thanks!

I am trying to use the TLV2241 DIP package IC to make a relaxation
oscillator(square wave oscillator using positive feedback). I first
simulated the design in spice (both ORCAD PSPICE and WINSPICE). I used
the SPICE model of the TLV2241 provided in the data sheet provided by

Well , I'll put this crazy problem forward and see what comes back. The
project is to have a candle (modified or 'gimmicked' I guess) under a
cup which is face down  on a table. When the cup if lifted up (hence
revealing the candle) the candle is already lit. The solution I have

Could someone explane me some basic issues of power tranfer in RF
amplifier stages.
1. How power is transferred from power transistor to antenna from
physical point of view, is antenna acting as a load.. Can it be

This is more of an electricity question than electronic but: We just
finished running water and power to a new construction site.  Water is in a
copper pipe run about 1,000' through the woods burried about 2' deep that
just ends in a 2' vertical piece with a faucet on top.  Power ...

For using an AC switch is it recommended to switch only live wire by
using SPST or switch both live and nuetral using DPST ?

I'm trying to build a circuit that calls for these three Transistors.
My local guy does not have them. I would rather buy from him than some place
I have to have them shipped into, added cost etc.
Who knows they may be obsolete?

I would like to calculate how long an LED will stay lit given a
specific power source.  I need to know what the smallest battery I can
use in a project and still get n hours of operation.
For example:

To All,
I have an interesting problem that I need to solve. I have an older
electronic blackjack machine that has blown the coin hopper pay out circuit.
No schematic of the board is available and the pcb has a 25 cent sized

We have an exhibit at our local science museum that is a 3-4' 1" diameter tube
with about 150' of wire wrapped around 8" of one end. First 75' were wound, and
then another 75'. An LED is connected across the wires. When a cow magnet is
dropped down the tube, the LED lights ...

The main point of my question is to get a general idea on what kind of power
usage AC power adapters consume when plugged into a household outlet.  Why?
Because even if you have nothing feeding off of the walwart it is still warm
to the touch and that would indicate that it is ...

I was just wondering why the pic16f676 (and most others)
use bank0 and bank1 to access registers. Would it be such
an overhead to use a 15 lines flash memory instead of just
14, this way we could have a full 8 bit for the registers instead