Electronic Circuits and electronic circuits, electronic schematics plus an extensive resource for hobbyists, inventors and engineers

DiscoverCircuits.com, has 45,000+ electronic circuits, cross-referenced into 500+ categories.
We have searched the web to help you find quick solutions & design ideas.

Got Designs?
Please eMail
if you want me to link to and/or post your original design
NOTE:  We make every effort to link to original material posted by the designer. 
Please contact us if our link is not to your site!  Thanks.


Tester or Measurement (Instrument) Circuits

Test Equipment:  #'s - A        B - D        E - G
H - L        M - O        P - S        T - Z


Last Updated: November 22, 2021 03:00 PM

Capacitance Proximity Switch
Draws very low power - Ideal for battery-powered applications
6 Models Available - Call 806-778-8407




Links to electronic circuits, electronic schematics and designs for engineers, hobbyists, students & inventors:

Simple Circuit pH Meter, a Low Cost Adapter for Your Digital Voltmeter -  A pH meter is actually a precise voltmeter  that measures the generated voltage of a pH electrodes. The requirement of such meter is high input impedance and has the gain of  voltage-pH conversion.__ 

Simple Circuit Phase Meter Operates to 10 MH -  07/04/96 EDN Design Ideas:  You need phase measurements to set up and verify electronic devices in amplifiers and in audio, control, ultrasound, and echo systems.  Phase measurements can be problematic, because not many simple, inexpensive phase meters are available.  Moreover, using an oscilloscope is time-consuming and imprecise.  The phase meter described Design by Ronald Mancini, Harris Semiconductor, Melbourne, FL

Simple Circuit polarity Detector -  This tester can be used to check the polarity of any power source, and is therefore very useful when installing automotive equipment, alarm systems or anything else you can think of.  Because this circuit is so simple and cheap, even frying one with an over voltage is not a big deal __ Designed by Aaron Cake

Simple Circuit Prevents Processor Latch-up -  03/04/99 EDN Design Ideas:  (contains several designs, scroll to find this one) The circuit in Figure 1 uses a Dallas Semiconductor DS1820 one-wire digital thermometer in a multipoint temperature-measurement system.  The DS1820 sensor allows distributed temperature measurement and uses only one wire for both data communication and the power supply.  You can easily connect the one-wire interface to a µC (in this example, a PIC 16C63).  The application accommodates as many as 16 DS1820 sensors in a 100m-long network, dubbed MicroLAN by Dallas.   Design by Michal Koby lecki and Wojda Wlodzimierz, MK Design, Warsaw, Poland

Simple Circuit Procedure Tests Transducer -  03/01/96 EDN Design Ideas:  Testing electromechanical transducers can be as simple as measuring a dc voltage.  The circuit in Figure 1 and an accompanying test method enable you to measure the damping coefficient ([beta]) of speakers, microphones, seismic geophones, and other transducers that exploit electromagnetic phenomena.  You can also tailor this method for testing electrostatic devices, such as capacitive micromachined sensors.  in general, you can measure the damping in any second-order system or signal, which conforms to the following basic equation for the free transient process Design by Alexander Belousov, SMP Inc Long Island City, NY

Simple Circuit Produces a Less than 25 Nsec Pulse -  05/11/00 EDN Design Ideas:  in many testing situations, a circuit that can produce a short pulse is useful.  You can use a short pulse to test trigger or interrupt-pulse-width requirements and to mimic glitches or noise on inputs, for example.  in some cases, short pulses with long delays between them are desirable.  For these cases, a function generator is inadequate because you can reduce the duty cycle low enough to produce low-nanosecond pulse widths only at relatively high frequencies.  Although purely analog circuits can generate short pulses, input and output loading and buffering propagation delays create problems with interfacing them to TTL-compatible circuitry.   Design by Andy Brandenberger, National Instruments, Austin, TX

Simple Circuit provides high-side current sensing -  10/12/00 EDN Design Ideas:  in power supplies or battery chargers, you often need information about the current flowing in the high-side rail.  Figure 1 shows a common circuit for obtaining this information.  The circuit provide as a groundreferenced voltage pr Design by M Ossmann and B Kazay, Aachen University of Applied Sciences, Germany

Simple Circuit pulse oximetry for wearable Monitor -  EDN Design Ideas:  09/14/2014     Use this circuit as the “heart” of a pulse oximeter and oxygen saturation monitor. Design by Martin Jagelka , Martin Daricek & Martin Donoval

Simple Circuit Rain Detector -  Who needs a rain detector? How hard is it to look outside to see if it's raining? But a rain detector can come handy when you're distracted; it will save you the trouble of looking out the window every second when you want to catch the start of a rain storm, or cover some water sensitive stuff on your backyard.  The following schematics are simple, but they can give design ideas or serve as a part of a more complex circuit like a computer weather data collection system.  it all depends on your dedication, skill and expertise level__ hobbyteam @ hobby-hour.com

Simple Circuit regulator Monitors its input voltage -  09/12/97 EDN Design Ideas:  Two- and three-cell portable systems, such as medical sensors, often monitor their battery input to obtain an early warning of a loss of battery voltage.  Typically, this warning is a digital signal that a comparator generates and then sends to the microcontroller.  The circuit in Figure 1 presets one side of a dual linear regulator to generate 2.84V at 100 mA.  The other side operates open loop, as a comparator, to generate the low-battery warning.  both side as are capable of delivering 100- mA output current.  Resistors R1 and R2 determine the low-battery threshold, according to Design by Larry Suppan and Luong Huynh, Maxim Integrated Products, Sunnyvale, CA

Simple Circuit RF Power Meter -  Here is a simple set up which will enable them to measure the out put power of their transmitter.  All that they require is a good multimeter which has a sensitivety of 20k ohms/4 Watts which is adequate for low power transmitters.  __ 

Simple Circuit RF Probe -  indispensable for any RF work.    Uses just 4 passive components  __ Designed by Rod Elliott  ESP

Simple Circuit safely Deep-discharges NiCd battery  -  04/29/99  EDN-Design ideas –  NOTE:  Scroll to find this circuit.   Also available at - http://m.eet.com/media/1150682/25098-42999dI     Nickel-cadmium (NIC d) batteries can possess an undesirable memory effect due to partial discharges.  The remedy is a complete discharge before charging again. Figure 1a shows a simple circuit that performs this feat.  Design by Jim Hagerman, Science & Technology International, Honolulu, HI

Simple Circuit Scheme Detects shorts -  07/08/99  EDN Design Ideas:  NOTE:  File contains multiple circuits.  Scroll to find this one.  When you manually assemble complex boards, it’s common to short-circuit adjacent component or IC pins.  Determining which section of the circuit you have shorted is not too difficult, but finding the precise point where the short exists can be a formidable task, because the short may be under a surface-mount component. Design by Luis Miguel Brugarolas, SIRE, Madrid, Spain

Simple Circuit serves as milliohmmeter -  04/15/04 EDN Design Ideas:  When I was recently debugging a design, I discovered that a short circuit existed from a ground plane to a power plane.  I did not have access to a milliohm meter or an equivalent tester for locating this type of short circuit.  So, I logged onto the internet to find an easily constructible milliohm meter Design by AM Hunt, Lancaster Hunt Systems Ltd, Shepperton, UK

Simple Circuit Servo Tester -  This is a simple servo tester which will comprehensively test the capabilities of almost any modern servo. it has two pushbuttons, CENTRE and SWEEP and a potentiometer which works as follows: __ Designed by Edward M

Simple Circuit setup tests bit-error rate -  18-Mar-04 EDN Design Ideas:  Traditionally, the reception quality of a digital receiver is expressed in terms of BER (bit-error rate].  This figure is the proportion of received bit errors in a given period.  Typically, you measure the BER in the lab by applying an RF signal, modulated by a pseudorandom code, to the receiver under test Design by Israel Schneiderman, Rosslare Israel Ltd, Rosh Ha'ayin, Israel

Simple Circuit Suits Quadrature Detection -  08/17/12  EDN Design Ideas:  (Originally published in the August 22, 1985, EDN-Design ideas) A circuit generates an output voltage that you can measure to determine whether two sine waves have a quadrature relationship.  The circuit in Figure 1 generates an output voltage that you can measure to determine whether two sine waves have a quadrature relationship.  if the output voltage is 0V, the inputs (ϕ1 and ϕ2) are exactly in quadrature.  if the inputs are other than 90° out of phase, a dc voltage appears at the circuit’s output.   Design by SL Black and HL Maddox, AT&T Technologies, Columbus, OH

Simple Circuit Technique Measures Small Capacitance -  09/01/97 EDN Design Ideas:  A simple technique (Figure 1) can measure small capacitance, such as the capacitance of a scope probe (Figure 3a) , a 10-pF capacitor (Figure 3b) , and a pc-board trace (Figure 3c).  The idea is to use a ramp generator and an oscilloscope (Figure 1a) to measure the delay in the ramp that corresponds to the capacitance.  Equations provide the best explanation of how the technique works.  For the circuit in Figure 1b, which drI ves channel 2 of the oscilloscope,  Design by Rich Kochis and Joe Eccher, Hewlett-Packard, Greeley, CO

Simple Circuit Test Setup Performs Functional Testing of Linear, Single-Cell Lithium Chargers -  10-May-07 EDN Design Ideas:  A handful of off-the-shelf components makes a test setup that allows you to test the operation of a linear single-cell lithium charger Design by Marián Štofka, Slovak University of Technology, Bratislava, Slovakia

Simple Circuit Tester Checks Christmas-Tree Lights -  12/23/99 EDN Design Ideas:  Why is it that you always test 48 bulbs before you find the bad one in a 50-light string? This simple circuit allows you to divide and conquer, greatly reducing the time it takes to find the bad bulb. Design by William Dias, Brown & Sharpe, North Kingstown, RI

Simple Circuit tester checks LCDs -  10/03/02 EDN Design Ideas:  RF oscillator uses current-feedback op amp - Manufacturers of electronic equipment use LCDs for calculators, watches, mini-videogames, and pagers, for example.  in comparison with LED-based displays, which consume power on the order of tens of milliwatts, an LCD consumes only a few microwatts.    Design by D Prabakaran, NL Polytechnic College, Tamil Nadu, India

Simple Circuit Tests Twisted-Pair Cables -  01/19/12 EDN Design Ideas:  Quickly test a cable containing twisted-wire pairs and detect open or reversed pairs, shorted pairs, and shorts between unrelated pairs.  Using the system shown in Fig 1, you can quickly test a cable containing twisted-wire pairs and detect open or reversed pairs, shorted pairs, and shorts between unrelated pairs.  The tester consists of an active test set that plugs into one end of the cable, and a passive terminator that plugs into the other end. (An RS-449 cable is used as an example.)  Design by Mark D Braunstein, Contel Information Systems, Fairfax, VA

Simple Circuit Thermocouple Amplifier -  Continuing with the thermocouple interface concept, the next step is to amplify the TC's millivolt signal into a more readable analog voltage, on the order of 0 to 5VDC.  This simple circuit fits the bill.  The LM358N is a dual op-amp IC .  i'm quite sure any op-amp IC would do fine, just be sure it can accept a Vcc which is compatible with your battery pack.  The IC draws ~ 1.0 mA.  __ 

Simple Circuit VLF, PI & BFO -  Metal detector theory - Metal detectors are used in a wide range of applications from landmine detection to safety in airports, office buildings or schools.  They can also be useful around the house to help locate lost coins, jewelry, keys and gas lines.__ hobbyteam @ hobby-hour.com

Simple Circuit Ways to Measure Current-LTC6101, LTC6102, LTC6103, LTC6104 -  Measuring current is one of the basic requirements in many electronic systems; whether for precise control or simple protection of circuit elements.  A family of new devices from has been produced to greatly simplify the measurement of DC or AC current.  Using only external resistors, each small device can be __ Linear Technology/Analog Devices App Note, Jon Munson-Applications Engineer-Amplifier Products Mar 15th 2009

Simple Crystal Tester -  Here is a simple circuit that can be used to test a crystal before using it in a circuit.  The circuit is built around two BC547 transistors (T1 and T2) and...__ Electronics Projects for You

Simple Light & Sound Indicator for Mains Power Supply -  While repairing or installing electrical machines in a building, the AC mains power supply is switched off from the mains electrical switchboard installed outside the building.  There is a chance that...__ Electronics Projects for You

Simple Metal Detector -  Two transistors and a LM386 make a simple metal detector suitable for finding coins. __ Designed by Steve Hagerman

Simple Stereo VU Meter -  I like to see lights move to music.  This project will indicate the volume level of the audio going to your speakers by lighting up LEDS.  The LEDs can be any color so mix them up and really make it look good.  The input of the circuit is connected to the speaker output of your__ 

Simple Tester for 74xx04 & 74xx14 ICs -  The integrated circuits (IC s) 74xx04 and 74xx14 are very frequently used and reused during circuit design.  Here xx stands for HC, HCT, AC and LS, etc.  Sometimes, the internal inverters of...__ Electronics Projects for You

Simples sort out the highest voltage -  11/09/06  EDN Design Ideas:  Greatest-of-three voltage detector drives indicators and external display Design by Ezio Rizzo, Nova SNC, Genoa, Italy, and Vincenzo Pronzato, Felmi SRL, Genoa, Italy

Simplified DC Motor Torque Control -  The LT6109 is a complete high side current sense device that incorporates a precision current sense amplifier, an integrated voltage reference and two comparators.  Two versions of the LT6109 are available.  The LT6109-1 has the comparators connected in opposing polarity and the LT6109-2 has the comparators connected in the same __ Linear Technology/Analog Devices App Note, Sep 7th 2011

Simplified DC Motor Torque Control -  The LT6108 is a complete high side current sense device that incorporates a precision current sense amplifier, an integrated voltage reference and a comparator.  Two versions of the LT6108 are available.  The LT6108-1 has a latching comparator and the LT6108-2 has a non-latching comparator.  in addition, the current sense amplifier __ Linear Technology/Analog Devices App Note, Sep 7th 2011

Simplified DC Motor Torque Control-LT6109 -  The LT6109 is a complete high side current sense device that incorporates a precision current sense amplifier, an integrated voltage reference and two comparators.  Two versions of the LT6109 are available.  The LT6109-1 has the comparators connected in opposing polarity and the LT6109-2 has the comparators connected in the same__ Linear Technology/Analog Devices App Note, Sep 7th 2011

Simulate digital filters in PSpice -  04/17/08  EDN Design Ideas:  You can simulate digital filters in PSpice by using transmission lines as delay elements Design by David Báez-López, Department of Electrical and Computer Engineering, Ryerson University, Toronto, ON, Canada

Simulate signals for telecomm tests -  9/11/98 EDN Design Ideas:  NOTE:    FILE
has several circuits, please scroll to find this one.  The circuit in Figure 1  is a miniature gadget that is heLPFul in telecommunication applications.  The function of the device is to simulate data flow with predefined patterns and use these patterns to check a cable's or a receiver's functionality.  The circuit generates a signal in accordance Design by Samuel Kerem, Patton Electronics, Gaithersburg, MD

Sine Wave Generator -  A classic Wien Bridge oscillator using an Op-Amp covering a frequency range of 15 to 150kHz in four switched steps.   __ Designed by Andy Collison

Single 5V Supply Linearized 0°C to 400°C Platinum RTD Amplifier -  The LTC2053 is a high precision instrumentation amplifier.  The CMRR is typically 116dB with a single or dual 5V supply and is independent of gain.  The input offset voltage is guaranteed below 10μV with a temperature drift of less than 50nV/°C.  The LTC2053 is easy to use; the gain is adjustable with two external resistors, __ Linear Technology/Analog Devices App Note, Mar 30th 2010

Single 5V Supply Precision Linearized 0°C to 400°C Platinum RTD Signal Conditioner -  The LTC6943 is a monolithic, charge-balanced, dual switched capacitor instrumentation building block.  A pair of switches alternately connects an external capacitor to an input voltage and then connects the charged capacitor across an output port.  The internal switches have a break-before-make action.  An internal clock is provided and its frequency can be adjusted with an external capacitor.  The LTC6943 can also be driven with an external CMOS clock. 
 
__ Linear Technology/Analog Devices App Note, Mar 30th 2010

Single chip Detects optical interruptions -  03/01/01  EDN Design Ideas:  Setting up a light beam and detector to count objects on a conveyer belt, sense security intrusions, or drive a tachometer is simple.  However, the task is no longer trivial if you add ambient light or multiple beams, limit optical power, or extend the dis Design by Frederick M Baumgartner, FM Broadcast Services, Parker, CO

Single chip digital voltmeter using ICL7129 -  in this circuit we have used IC L7106. This a singlechip IC , which is used for volt, current and temperature measurement meter.__ 

Got Designs?
Please eMail
if you want me to link to and/or post your original design Thanks.

      <<<         >>> 


Test Equipment:  #'s - A        B - D        E - G
H - L        M - O        P - S        T - Z


HOME Schematics Index Hobby Corner Dave's Circuits Contact Info
Imagineering Ezine Dave Johnson, P.E. Faraday Touch Switches


 About Us   |  Advertise on DiscoverCircuits.com   |   Report Broken Links  |   Link to DiscoverCircuits.com  |  Privacy Policy

Copyright  January, 1998 - November, 2021     David A. Johnson  All Rights reserved. 

 COPYING any content or graphics to your web site is EXPRESSLY PROHIBITED!