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

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

HOME Schematics Hobby Corner Dave's Circuits Electronic Resources Contact Info
Imagineering Ezine    Discover Solar Energy Dave Johnson & Associates Faraday Touch Switches
Welcome to DiscoverCircuits.com - online since 2002

See Media Kit for
Advertising Opportunities

Attention Designers:  Please alert us by eMail if we have linked to sites
where your original material has been copied without your permission.
We will change to the LINK to your site.  
Thank you.

 


Tester or Measurement (Instrument) Circuits

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


Last Updated: October 24, 2017 02:55 PM
Circuits Designed by Dave Johnson, P.E. :

High Speed Light Detector from FET Input -  This circuit is yet another design that converts current from a PIN photo diode to a voltage.  it has a bandwidth that extends beyond 50MHz . . . Hobby Circuit designed by David Johnson P.E.-June, 2000

High/Low Voltage Tester on AC Power Line  -  if you wish to test a line-powered device under both a 15% high and a 15% low voltage condition, you can use the circuit below.  The circuit uses an 18v transformer with a 3 amp rating.  A double pole, double throw toggle switch then switches in the . . . Hobby Circuit designed by David Johnson P.E.-March, 2010

High-speed 75MHz light receiver -  This circuit uses one tiny C-MOS inverter IC to form a modulated light receiver with a very fast response.  it is designed around a PIN photo diode that is packaged for use with plastic optical fibers.  it can be used as an optical fiber receiver.  By using the open end of the optical fiber it can "sniff" out any modulated light signals. . . Circuit by Dave Johnson P.E.-June, 2000

Home Made Geophone Detects Foot Steps -  A home made geophone is made from a strong magnet, a coil of wire and a rubber band.  The circuit is sensitive enough to detect the vibrations of a nearby foot stomp.  it could be used as an earthquake detector. . . . Hobby Circuit designed by David Johnson P.E.-June, 2006

Consulting Services include:
Applications Engineering   --    Design & Development
Electronic Circuit Design   --   Custom Test Fixtures

Call 806-368-7747


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

High Resolution Battery-Powered Robust Type K Thermocouple Signal Conditioning Amplifier with Cold Junction Compensation -  The circuit is used as a plug-in adapter for common digital multimeters and is completely portable.  This circuit employs the LT1025 thermocouple compensator to improve accuracy over a wide range of ambient conditions and is mounted close to the thermocouple connection points for optimal thermal tracking.  it precludes the need __ Linear Technology/Analog Devices App Note, Apr 8th 2010

High Resolution Type S Thermocouple Digitizer with Improved Cold Junction Compensation -  This simple interface circuit that demonstrates the practicality of direct thermocouple connection to the LTC2400 using low output voltage thermocouples (a Type S thermocouple, as shown, produces a full-scale output voltage of 18mV).  This circuit uses the LT1025, a micropower thermocouple cold junction compensator, to sense __ Linear Technology/Analog Devices App Note, Apr 8th 2010

High Side Current Sense & Fuse Monitor -  The LT6100 can be used as a combination current sensor and fuse monitor.  This part includes on-chip output buffering and was designed to operate with the low supply voltage (≥2.7V) , typical of vehicle data acquisition systems, while the sense inputs monitor signals at the higher battery bus potential.  The LT6100 inputs are __ Linear Technology/Analog Devices App Note, Mar 30th 2010

High Side Current, Input Voltage & Open Fuse Monitoring with a Single LTC4151 -  The LTC4151 is a high side power monitor that operates over a wide voltage range of 7V to 80V.  in default operation mode, the onboard 12-bit ADC continuously measures high side current, input voltage and an external voltage.  Data is reported through the i2C interface when polled by a host.  The LTC4151 can also perform on-demand__ Linear Technology/Analog Devices App Note, Apr 26th 2010

High Side Power Sensing with Onboard ADC & I2C -  The LTC4151 is a high side power monitor that operates over a wide voltage range of 7V to 80V.  in default operation mode, the onboard 12-bit ADC continuously measures high side current, input voltage and an external voltage.  Data is reported through the i2C interface when polled by a host.  The LTC4151 can also perform on-demand__ Linear Technology/Analog Devices App Note, Apr 26th 2010

High Speed Light Detector from FET Input -  This circuit is yet another design that converts current from a PIN photo diode to a voltage.  it has a bandwidth that extends beyond 50MHz . . . Hobby Circuit designed by David Johnson P.E.-June, 2000

High Temperature Alarm -  The high temperature alarm will beep and LED blinks when the temperature of the device increases abnormally.  This simple over heat alarm is to monitor heat generating devices such as motor, inverter etc.  The circuit is a simple astable multivibrator using the low power CMOS timer IC 7555 which is the low power version of the __ Designed by D Mohankumar

High Voltage Generator for Geiger Tubes -  The following two circuits are an improvement over the older circuits below.  The circuits are shown generating 500 volts but they may be modified to supply a couple of hundred to nearly 1000 volts by changing the zener diodes.  The difference is subtle; the feedback signal increases the voltage on the base of the 2N4403 to stop the oscillator instead of stealing current from the capacitor on the emitter.  The result is much lower power dissipation when there is little or no load on the high voltage __  Contact:  Charles Wenzel of Wenzel Associates, Inc.

High Voltage Megohm Tester -  Resistance measurements far beyond where a DMM will go__ SiliconChip

High Voltage Power Supply step-up converter using a MC34063 ideal for a geiger counter or nixie tube -  A basic building block for a Geiger Counter (Nixie Tube)  __ Designed by Alexander C. Frank, aka Ajarn Changpuak

High Voltage Stun Gun -  This device produces high voltage pulses discrupting muscles and nervous sYstem, leaving anyone who touches it in a state of menthal confusion.  Can be used agains ferocious animals or attackers, BUT REMEMBER, this device may be illegal in your state (for eg where I live, these devices are banned).  it is quite dangeros for peoples experiencing cardiac problems, and for electronic equipment (like peacemakers) , since it generates some RF.  Don't attept irresponsible actions with this device, it is not a toy. __ Designed by Jonathan Filippi

High Voltage/Current & Temperature Monitoring -  The LTC2990 is used to monitor system temperatures, voltages and currents. Through the i2C serial interface, the device can be configured to measure many combinations of internal temperature, remote temperature, remote voltage, remote current and internal VCC. The internal 10ppm/°C reference minimizes the number of supporting components and area required. Selectable address and configurable functionality give the LTC2990 flexibility to be incorporated in various systems needing temperature, voltage or current data.__ Linear Technology/Analog Devices App Note, Oct 26th 2010

High/Low Voltage Tester on AC Power Line  -  if you wish to test a line-powered device under both a 15% high and a 15% low voltage condition, you can use the circuit below.  The circuit uses an 18v transformer with a 3 amp rating.  A double pole, double throw toggle switch then switches in the . . . Hobby Circuit designed by David Johnson P.E.-March, 2010

High-accuracy Digital LC Meter -  Here's a handy piece of test gear you can build for yourself - a Digital LC Meter for measuring inductance and capacitance over a wide range.  it's based on an ingenious measurement technique, delivers surprising accuracy and is easy to build.__ SiliconChip

High-Current, High-Voltage Battery Capacity Meter, Pt.2 -  Last month we presented the full description, operation and construction details of our new Battery Capacity Meter.  This month we guide you through the once-only setup and calibration.  We also explain in detail how to use it! __ SiliconChip

High-efficiency power supply for 1W Luxeon Star LEDs -  Easy-to-build design lets you use a pair of 1.5V "D" cells and includes a brightness control to further extend the battery life.__ SiliconChip

High-Impedance FET probe extends RF-spectrum analyzer's usable range -  21-Jul-05 EDN Design Ideas:  Op amp and careful design/construction build high-impedance RF probe __ Circuit Design by Steve Hageman, Windsor, CA

High-Impedance RF Probe -  Schematic only __ Designed by va3iul

High-Impedance voltmeter -  An ideal voltmeter has infinite input impedance, meaning that it draws zero current from the circuit under test.  This way, there will be no "impact" on the circuit as the voltage is being measured.  The more current a voltmeter draws from the circuit under test, the more the measured voltage will "sag" under the loading effect of the meter, like a tire-pressure gauge __ Designed by © EETech Media, LLC.

High-Isolation converters use off the shelf magnetICs -  07/22/99 EDN Design Ideas:  isolated flyback converters usually evoke thoughts-or bitter memories-of custom transformers, slipped delivery schedules, and agency-approval problems.  Off-the-shelf flyback transformers carry isolation ratings of only 300 to 500V and rarely of as much as 1 kV.  Gate-drive transformers are readily available from stock with high isolation ratings and low cost, but they are wound  __ Circuit Design by Mitchell Lee, Linear Technology Corp, Milpitas, CA

Highly sensitive & selective Field Strength Meter system -  A field strength meter is a very handy tool for locating a transmitter.  A sensitive field strength meter by itself has some limitations, however:  it will respond to practically any RF signal that enters its input.  This property has the effect of limiting the effective sensitivity of the field strength meter, as any nearby RF source (or even ones far away, if the meter is sensitive enough...) will effectively mask the desired signal. __ Designed by Clint Turner, KA7OEI

High-Power LED Stroboscope -  Stroboscope is a convenient and accurate enough instrument to measure speeds of rotating objects in homes or industries. One can use it to find the speed of fans, motors or any...__ 06/22/2015 - EFY

High-Resistance Meter -  This resistance meter can measure resistances up to 200 mega-ohms.  The value of the resistance is indicated on a linear meter scale (0-100 uA).  The operation of the circuit is based...__ Electronics Projects for You

High-side current Monitor operates at High-Voltage -  07/22/04 EDN Design Ideas:  The simplest technique for measuring current in an actuator or a motor is to monitor the ground current with a resistive element between the load and the ground.  Because the device and its associated electronics share a ground potential, you need to amplify only the ground-current signal.  This approach, however, does not detect device short circuits to ground, which can overload the high-side d __ Circuit Design by Greg Sutterlin and Brian Whitaker, Maxim Integrated Products, Sunnyvale, CA

High-Side Current Sense Causes Little Error -  03/16/95 EDN Design Ideas:  Measuring dc would be simple if you could always reference your measurement signals to the positive rail.  Unfortunately, most current-metering applications require a ground-referenced output.  Typically, the signal that you want to measure consists of a small differential signal that rideas on a large common-mode voltage __ Circuit Design by Charles L Langner, Broadcast Electronics Inc, Quincy, IL

High-Side Current Sensing with Input Overvoltage Protection  -  Conversely, when the input common-mode voltage approaches V EE + 1.5 V, Q5 to Q8 shut down as i2 reaches its minimum voltage compliance__ Analog Devices from the Lab

High-Side Current Sensor Monitors Negative Rail -  17-Apr-03 EDN Design Ideas:  All dedicated current-sense amplifiers provide high-side sensing on a positive supply, but you can adapt such circuits for monitoring a negative supply (Figure 1).  The positive-supply pin, V+, connects to the system's positive supply, and the ground pin, GND, connects to the negative supply, VEE.  That arrangement monitors the negative supply and provide as a positive output voltage for the extern __ Circuit Design  Ken Yang, Maxim Integrated Products, Sunnyvale, CA

High-side current-sensor has period output -  03/07/02 EDN Design Ideas:  You use high-side current monitoring in many battery-powered products that require accurate monitoring of load current, charger current, or both.  in applications for nonportable designs, high-side-current monitoring serves as a power-supply watchdog that can flag a failure in downstream devices __ Circuit Design by Greg Sutterlin, Maxim Integrated Products, Wexford, PA

High-Side Current-Shunt Monitor Offers Reduced Error -  12/15/10 EDN Design Ideas:  A Darlington pair, with lower base current, reduces measurement errors.  [Design ideas by Marián Štofka, Slovak University of Technology, Bratislava, Slovakia __ Circuit Design by Marián Štofka, Slovak University of Technology, Bratislava, Slovakia

High-Side Transimpedance Amplifier & APD Monitor -  Current through a photodiode with a large reverse bias potential is converted to a ground referenced output voltage directly through an LTC6101.  The supply rail can be as high as 70V.  Gain of the I to V conversion, the trans- impedance, is set by the selection of resistor RL.  __ Linear Technology/Analog Devices App Note, Mar 30th 2010

High-speed 75MHz light receiver -  This circuit uses one tiny C-MOS inverter IC to form a modulated light receiver with a very fast response.  it is designed around a PIN photo diode that is packaged for use with plastic optical fibers.  it can be used as an optical fiber receiver.  By using the open end of the optical fiber it can "sniff" out any modulated light signals. . . Circuit by Dave Johnson P.E.-June, 2000

High-speed lightwave component analysis -  Application Note__ Aligent

High-Speed Op Amp Enables IR-Proximity Sensing -  06-Aug-09 EDN Design Ideas:  IR (infrared]-proximity sensors can sense the presence of an object, its distance from a reference, or both.  Applications include speed detection, sensing of the hand in automatic faucets, automatic counting or detection of objects  __ Circuit Design by Arpit Mehta, Maxim Integrated Products Inc, Sunnyvale, CA

High-speed peak Detector uses ECL comparator -  09/26/02 EDN Design Ideas:  Professional electronics designers often use peak-detector circuit sin such applications as amplitude measurement, automatic gain control, and data regeneration.  You can build a simple and fast peak detector from a serial diode and a shunt capacitor, but it suffers from serious inaccuracy that stems from the diode's forward-voltage drop __ Circuit Design by Przemyslaw Krehlik and Lukasz Sliwczynski, Institute of Electronics, Krakow, Poland

High-Temperature Thermometer/Thermostat -  Need to measure or control temperature over a very wide range? Now you can do it with this compact unit which hooks up to a K-type thermocouple.  it drives a relay which can be used to precisely control the temperature in ovens, kilns, autoclaves, solder baths or at the cold end of the spectrum, fridges and freezers.  it is based on an Analog Devices AD8495 precision instrumentation amplifier with thermocouple cold junction compensation.__ SiliconChip

High-voltage Amplifier drives piezo tubes -  7-Dec-04 EDN Design Ideas:  Piezoelectric tubular positioners that drive manipulators in scanning tunneling microscopes require high-voltage, low-current drive circuits.  The circuit in Figure 1 can drive high-resistance, low-capacitance piezoelectric loads at a -3-dB bandwidth of 6 kHz.  it offers a low-cost alternative to commercial driversPDF has several circuits, please scroll to find this one __ Circuit Design by Bipin Duggal, Netaji Subhas Institute of Technology, New Delhi, India

High-voltage current-feedback Amplifier is speedy -  04/26/01 EDN Design Ideas:  The circuit in Figure 1 powers a microparticle and nanoparticle ion trap through a 1-to-5-turns-ratio, high-voltage transformer.  it also works successfully as a driver for a piezo-tube scanner and in a near-field scanning optical microscope.  The circuit is robust and works with supplies ranging from ±50 to ±230V __ Circuit Design by Joseph Ting, Institute of Atomic and Molecular Sciences of the Academia Sinica, Taipei, Taiwan

Hippasian nonlinear VFC stretches dynamic range -  19-Feb-09 EDN Design Ideas:  A voltage-to-frequency converter uses square roots to extend dynamic range by orders of magnitude __ Circuit Design by W Stephen Woodward, Chapel Hill, NC

Home Made Geophone Detects Foot Steps -  A home made geophone is made from a strong magnet, a coil of wire and a rubber band.  The circuit is sensitive enough to detect the vibrations of a nearby foot stomp.  it could be used as an earthquake detector. . . . Hobby Circuit designed by David Johnson P.E.-June, 2006

Home Made Metal Detector -  This homemade metal detector circuit will help you find objects composed of materials with relatively high magnetic permeability.  it is not suitable for buried coins discovery that is not sensitive enough but you can detect pirates treasures!  The metal detector is powered by 2 × 9V batteries, each of it charges with 15mA.  L1 detector__ 

Home-Brew electronic altimeter -  A while back, I decided I wanted an altimeter to record how high my rockets were flying.  I didn't want to buy one, since a) they aren't cheap (at least, not the ones which do everything I want them to do) , and b) buying one is far too easy.  I considered the CP Technologies kit, which is based on the Missile Works RRC2,  __ Designed by James Padfield

HomebreW RF Design Test Equipment & Software -  Simple and useful tools for the RF experimenter.  __ Green Bay Professional Packet Radio

HomebreW signal generator tunable from 3 to 30 Mhz -  Simple and useful tools for the RF experimenter.  __ 

Home-Built Magnetic Levitator -  With this assembly, I was able to suspend a magnet about 1" below an electromagnet.   Here are the details on the circuit design.  This project requires you to have some familiarity with building and testing electronic circuits.   A great way to start is to obtain an "Engineer's Mini-Notebook" book from Radio Shack, by Forrest M.  Mims iii, on building circuits.   He has a lot of different booklets out for all sorts of projects.   They go into a fair amount of detail so you'll start to learn how the circuits work, how to put things together, etc. __ Designed by Rick Hoadley

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

 


Imagineering Ezine    Discover Solar Energy Dave Johnson & Associates Faraday Touch Switches



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


Discovercircuits.com endeavors to credit original designers.   Please alert us by eMail so we can
delete links to material that have been copied without your permission
.   Thank you.


© Copyright of all original material on this website is the property
of David A. Johnson, P.E. (Dave Johnson & Associates ) unless otherwise noted.  

Linking is ALLOWED but COPYING any content or graphics to your web site is EXPRESSLY PROHIBITED.
All material is provided "as is" without guarantees or warranty of any kind, either expressed or implied.