Electronics Forum / Basics / December 2005

I was sent a power supply for a unit that requires 9 volts DC with
180ma.
The power supply says input 220v AC, not 110-220v,  so I guess that
means non switching, and is supposed to supply 300ma of current. .    I

Is there a way to calculate the amps a capacitor dischages through a short?
I have a "spot welder" made up of five large 150,000 uf (5 volt)computer
capacitors in parallel, which are charged to up using a 1 to 5 volt supply
and dischaged through a SCR to 2 beefy probes.  The purpose ...

I need to set my thinking straight on how to connect to a type-K
thermocouple...
The hot junction is straightforward. The "cold" end is terminated by a
plug. This will connect to a PCB-mounted socket, which will connect to an

I have a question about low pass filters.  I am designing a 2nd order lo
pass LC filter.  What determines the response type? (ie. butterworth
bessel, etc.)
Many thanks,

I received as a Christmas gift a 2-CDs-in-one-case pair of CDs, but I am
having trouble removing them from the case.  The CD on one side of a door
like panel (this internal panel holding both CDs) is held in place by a
"button" in the centre consisting of four barb-like hooks at 90 ...

Some references describe diode tempco as -2.1 mV per degree C and also
as 3300 parts per million.
If parts per million, then the tempco would vary with the forward
voltage of the diode, for example, with a very low forward current, Vf

Hi all, I was wondering if anyone could help with the following
question.
For the function, F(A, B, C, D) = (0, 2, 4, 5, 8, 10, 12, 13) give the
minimised sum-of-products solution.

Suppose we have  a raddar that works on Doppler principle.As an object
comes closer to the radar there will be a change in frequency(doppler
shift).What i am asking to know is if the object comes closer at a
greater speed is there going to be a change in the magnitude of the

I recently moved from a high voltage (240v) country to a  low voltag
country (120v). I brought along my home stereo system and some othe
small appliance that requires the input of 240v, to reuse thes
appliance / tv/ stereo in a low voltage country i bought step u

I'm trying to analyze a trivial common-source amplifier based on an IRFP9240
power P-channel MOSFET (datasheet at
http://www.irf.com/product-info/datasheets/data/irfp9240.pdf).
The circuit is simply this:

I got a Fluke 189 for Christmas and am wondering about this one feature,
it has an option when you are in the DC volts mode where it will tell
you the amount of AC in the DC.  My question is, if I were to hook the
same signal to a scope, would the value I see on the meter be the ...

obfuskacja_test_01@tlen.pl
obfuskacja_test_02[at]tlen.pl

Please let me know why tacho feed back is necessary?? Without Tacho the
Servo motor runs..
Help me..

I mean why we use 50/60 Hertz in houses why we dont use 400Hertz. i
know as we increase frequency losses increase but what is formula or
equation  for that.

I would be grateful for suggestions on constructing a simple random noise
generator.  Most of the noise should be within the audio spectrum.
R