|
Tester or
Instrumentation Circuits, Page 14
Testers:
#'s A-B
C D
E F-G
H-K L
M-O P
Q-R S
T U
V-Z
Last Updated on:
Monday, October 03, 2011 06:08 PM |
|
Circuits Designed by Dave Johnson, P.E. : |
- 1 AMP
CURRENT INJECTOR
When you need to measure resistance down to a few micro ohms, this circuit works
great. It is powered from two "C" cell batteries and is designed to inject a
well-regulated one amp of current into the unknown resistance. By measuring the
voltage drop across the resistor with a digital voltmeter, the resistance value can
be accurately measured. The circuit also is equipped with a low battery monitor.
Published in Popular Electronics, November 1992
|
- 120vac
Under Voltage Tester
Using a cheap 24vac transformer, this circuit can test a product under low 95vac
conditions. With the components show, it has a rating of 250 watts max.
|
- 20MHz VCSEL
3mW LASER TEST CIRCUIT
This circuit takes advantage of some new vertical cavity surface emitting lasers (VCSEL)
that don’t require light output control circuits. The circuit shows how to drive the
device from a single high speed CMOS IC. The circuit can easily be modified to
transmit signals from kilohertz to about 50MHz.
|
- 40KHZ LED
TEST SIGNAL GENERATOR
This 40KHz crystal controlled oscillator circuit drives an infrared LED with
powerful 40ma pulses. The circuit can be used to test optical communications
circuits, designed to receive 40KHz modulated light signals.
|
|
|
Links to electronic circuits,
electronic schematics, designs for engineers, hobbyists, students & inventors:
|
|
|
|
U.S. Navy TV-3/U Tube Tester manual - (circuit added 07/07/07)
|
|
UJT Test - This testing procedure is for use with a digital
multimeter in the OHM's test-range. The UJT is a solid-state
3-terminal (TO-18 case) emiconductor. UJT's are used in pulse/timing,
oscillator, sensing, and thyristor triggering circuits. The most common one
being probably the 2N2646 from Motorola…. [Tony van Roon's circuit] |
|
UL Ground Resistance Tester - UL requires that an electrical
system using a metal chassis earth ground connection have a resistance of
less than 0.1 ohms. This resistance must be tested with actual line current
in excess or 10 amps. The circuit shown uses a couple of LEDs to
indicate if in fact the resistance is less than 0.1 ohms. It uses a
modified transformer to produce a 2.5vac output with at least 10 amps of
supply current.... [Designed by David A. Johnson] |
|
Ultra Low Power LCD Indicator - This circuit serves as an
ultra-low power replacement for multiple LED on-off indicators. It also has
the advantage of being easy to read in full daylight. With the parts shown,
it is possible to display four bits of information…. [G. Forrest Cook] |
|
|
|
Ultrasonic Range Meter - This circuit is measuring the range to an object by
using ultrasonic transmitter and ultrasonic receiver. The distance is calculated by
PIC microprocessor and is displayed on the three digit 7-segment LED display. …....
|
|
Universal IR Remote Control Tester - This tester consists of two integrated
remote control receivers whose outputs drive an LED to indicate when a suitable
infrared signal is received. To cover all current infrared remote controls, one
receiver (the TSOP1736) has maximum sensitivity to carriers at 36 kHz, the other (the
TSOP1738) to carriers at 38 kHz.….must register on this site.... [Published in
Elecktor July/August 2010] |
|
Unusual clock with AT89C2051 - …. |
|
Use a PC's parallel port to program a clock source - 7-Dec-04 Issue of EDN
This Design Idea shows how you can use Linear Technology's LTC6903 programmable
oscillator as a clock source for direct-digital synthesis, data conversion,
switched-capacitor filtering, clock, and voltage-controlled oscillator circuits. The
LTC6903 operates from 2.7 to 5.5V with modest power consumption and can produce clock
signals at frequencies of 1 kHz to 68 MHz.... [Design Idea by William Grill, Honeywell
BRGA, Lenexa, KS] |
|
Use a switching regulator controller to generate fast pulses - 13-Apr-06
Issue of EDN Switching-regulator-controller ICs can deliver gate-drive pulses
with rise and fall times of less than 2 nsec, making them ideal candidates for
laboratory pulse-generators.... [Design Idea by Mitchell Lee, Linear Technology Corp;
Edited by Brad Thompson and Fran Granville] |
|
Use op amp injection for Bode analysis - 16-Sep-04 Issue of EDN Bode
analysis is an excellent way to measure small-signal stability and loop response in
power-supply designs. Bode analysis monitors gain and phase of a control loop. It
performs this monitoring by breaking the feedback loop and injecting a signal into the
feedback node and then comparing the injected signal with the output signal of the
control loop.... [Design Idea by Martin Galinski, Micrel Semiconductor, San Jose, CA] |
|
Use RS 232C port to measure pressure - 1-Aug-97 Issue of EDN A simple
circuit and accompanying software turn a pressure sensor into an accurate and cheap
pressure digitizer that works with any PC's RS-232C COM port. Many manufacturers make
micromachined silicon piezoresistive pressure sensors.... [Design Idea by W Stephen
Woodward, University of North Carolina--Chapel Hill] |
|
Use Your Printer Port as a High-Current Ammeter - 07/06/00 EDN-Design
Ideas....With a few inexpensive components and INT1Ch, you can turn the printer port
of your PC into a high-current ammeter.… [Design Idea by K Suresh, Indira Gandhi
Centre for Atomic Research, Kalpakkam, India] |
|
Using Vector Modulation Analysis in the Integration, troubleshooting & Design of
Digital RF Communications Systems - Aligent Application Note (app note
added 6/07) |
|
|
|
Testers: #'s
A-B C
D E
F-G H-K
L M-O P
Q-R S T
U V-Z
|
|
|
