First of all I'd like to thank everyone who responded to my earlier question about adding ESD protection - it all was very helpful information.
My new question is this: suppose we have a USB-powered microcontroller based device, and some of the uC pins are exposed as an external I/O port (i.e...
I have a device that was manufactured in the early 90's that uses LS7166 quadrature decoder chips. The AB inputs of the LS7166s were connected directly to external rotary encoders using DIN connectors. After many years of use and repeated plugging and unplugging of the DIN connectors almost all...
Hi,
I have a used Elenco Digital/Analog trainer, and on board there is an adjustable 0-20 VDC power supply. However, ever since I've had it it's only been able to adjust from 0 to 10 V. I've just gotten around to looking at it, and figured out the following:
- It seems like a standard LM317...
Hi,
I have a device which operates off of a 9V battery, and I'm investigating removing the need for a power switch as follows: the device has an earphone jack, and so I was thinking of using the shunt lead of the jack (which is grounded when no plug is inserted and is an open circuit otherwise)...
Hi everyone!
I'm sure most people are familiar with the hand-held LED
tester boxes that have come out on the market recently,
e.g. the ones that look like this:
http://www.ledtronics.com/ds/TST-1001/
For a while now I've contemplated how easy it could be to
make one yourself with an emphasis...
Just a question on how to interpret a specification for
a slug-tuned inductor which reads something like:
"+/- X uH". Does that mean that the range of inductance
from lowest value to highest value is 2X uH? This seems to
be the intuitive answer, but I just wanted to verify it.
Also, is there a...
I've got a 20-pin SDIP (shrink DIP) packaged IC, and I'm racking my brain trying to figure out the easiest way to
use it in my breadboarding projects and also for permanent
versions.
The idea list so far:
1. Etch my own SDIP-to-DIP adapter board. Would requiring
buying an SDIP socket.
2...
Imagine a device which takes an input signal, applies a
tuneable narrow bandpass filter followed by some sort of
gain control and then "emits" the intensity of the result
in one or more ways such as analog meter, audible tone,
bar graph, digital readout, etc.
It's kind of like a spectrum...
A control circuit I've got has the control (pin 3) of a 555
controlling an NPN transistor which itself controls a IRF710
MOSFET. In series with the MOSFET's gate is a James Bond
diode (last three digits "007" - can't make out the prefix).
The circuit appears to be intended for an...
Is there a simple way to use a volt meter (DMM or analog) to measure duty cycle? Assume the input is very clean -- steady and "rail to rail" signalling. Duty cycle is then just the time average of the input divided by the supply voltage.
My gut tells me there ought to be a simple way...
Here's my (obligatory) flashing LED question. Consider the 2-transistor flashing circuit at [link]http://www.uoguelph.ca/~antoon/circ/2qflash.htm[/url]
without the diode. My understanding of the way the circuit
works is:
1. C1 charges through R1, R2 and R3, and as it does so the
potential at...
I was wondering if someone could describe the theory of operation behind a frequency counter. I understand how a "digital" frequency counter works -- the input signal is assumed to transition between high and low logic levels, and the input pulses the clock signal of a counter...
