Electronics Forum / Basics / January 2007

I am trying to design an H-bridge base on MOSFETS.
My circuit under simulation was not working and founf this link.
http://www.armory.com/~rstevew/Public/Motors/H-Bridges/Blanchard/h-bridge.htm
I tried the circuit and it has the same problem as mine.

A quick question when and where should i use decoupling capacitors.
Circuits that i have built at uni have always been giving to us and
there are often these decoupling capacitors but it is never be
explained why they are used and when they should be used. Could anybody

I have connected 5 new NiMh batteries in series, each is rated at 3800
mAH.  When I connect a 10W, 6v halogen bulb to them it lasts about 2
hrs.  I expected longer than this, calculating that the current should
be 1.6 amps through the bulb, and the battery pack should have 5 x 3.8

I've always been singularly impressed by the people who can make lights
blink and robots roll and whatnot. I've been trying a foray into that
world for about a month now on and off with the apparently abandoned
USB-IR-Boy project.

http://www.gocs1.com/gocs1/Psionics/
Such handy schematics as the
"Brian Tuner"
PSIONIC-AMPLIFYING-HELMET

I have this DC-Jack with three pins: Center pin, shunt terminal, and
sleeve terminal. I don't know what each pin does. My guess is this :
http://img226.imageshack.us/my.php?image=dcjackgu3.gif
I am thankfull for any suggestions.

I am working on a project where I have to send signals from a PC (RS232
or USB?) to a 4-to-16 decoder. Basically, I need a way to send signals
from a PC to drive the 4 inputs of the decoder. Anybody knows an easy
way to do that?

Thanks in advance.
I'm looking for places on the net  that sell data books about
electronic parts.
Also, is there any recommended data book for electronic newbie?

I am an electrical engineering student and I am interested in circuit
design. Unfortunety I am not so familiar with analog design. Therefore I
want to place my question here in the newsgroup:
Is there a method to reduce jitter without the use of PLL? Where can I find

Ion Fan
I'm thinking of making an Ion Fan as described here
http://www.inventgeek.com/Projects/IonCooler2/Overview.aspx
Is there a way of beefing it up a bit more power arrfff arrff. :)

I found this PDF from Intersil:
http://www.intersil.com/data/an/an9415.pdf
I also found this page talking about op amp feedback:
http://www.ecircuitcenter.com/Circuits/opfeedback1/opfeedback1.htm

Can anyone suggest me books on Repair of On-Line UPS upto 80KVA

I am building a board where the power input can come from a battery or
an adapter. So, I used a 3-polled DC jack and draw this schematic:
http://img143.imageshack.us/my.php?image=dcjackde4.png.
My aim is that when a plug is connected to the jack, the Battery GND

Hello to the group,
The only experience I have with ultrasonics is that I built a bat
detector a few years ago which took in 40Khz and divided it down to
where I could hear the clicks of some types of bats (mostly the little

Would like to construct a project, evolving ultrasonic sensor.
1) The sensor is supposed to be in harsh environments, with air
turbulance. Does any one has suggestions how to over come this problem?
The turbulance source is 3 meters from the sensor, while the target is