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Tester or Measurement (Instrument) Circuits

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Last Updated: November 22, 2021 02:41 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:

Metal Detector 111 kHz -  Schematic only __ Designed by va3iul

Metal Detector 130 kHz -  Schematic only __ Designed by va3iul

Metal Detector 140 kHz -  Schematic only __ Designed by va3iul

Metal Detector 300 kHz -  Schematic only __ Designed by va3iul

Metal Detector 300 kHz PLL -  Schematic only __ Designed by va3iul

Metal Detector 300 kHz PNP -  Schematic only __ Designed by va3iul

Metal Detector 3xBJT Homemade -  Schematic only __ Designed by va3iul

Metal Detector 4001-ZL2PD -  Schematic only __ Designed by va3iul

Metal Detector 455 kHz -  Schematic only __ Designed by va3iul

Metal Detector 5.5 MHz -  Schematic only __ Designed by va3iul

Metal Detector 625 kHz -  Schematic only __ Designed by va3iul

Metal Detector 650 kHz -  Schematic only __ Designed by va3iul

Metal Detector a Pulse Induction Detector Pulse-1 -  Hundreds of this Detector have been built with Very favourable Feedback.  This is the Most Most Popular Project on my site.   __ Designed by G.L. Chemelec

Metal Detector based on the CS209 NoW Discontinued -  Especially Suited to find studs in Walls.  Note: this IC is discontinued and getting hard to obtain.   __ Designed by G.L. Chemelec

Metal Detector based on the TDA0161 -  A Simple design based on a TDA0161 IC that appears to give better results than the Discontinued CS209 and draws very little current from a 9 volt battery. __ Designed by G.L. Chemelec

Metal Detector Beat Balance -  Schematic only __ Designed by va3iul

Metal Detector Coils for my PI Detectors -  Due to the increasing number of Requests I have recieved.  I have now designed and built 2 new Coil Winding Jigs for my Radial Flat Coils.   __ Designed by G.L. Chemelec

Metal Detector Heathkit GD-1190 -  Schematic only __ Designed by va3iul

Metal Detector Heathkit GR-1290 -  Schematic only __ Designed by va3iul

Metal Detector Mk1 -  A fun metal detector to find coins at the beach __ Contact Collin Mitchell

Metal Detector Mk2 -  More sophisticated 5 transistor metal detector (BC547, BC557, BC338)  __ Contact Collin Mitchell

Metal Detector My Pulse-2 Induction Type Detector -  This is a Revised Version of the Pulse-1 above with Additional Controls for Possibly More Flexibility.  This Detector is Definately Not for the Beginner.   __ Designed by G.L. Chemelec

Metal Detector Pin Detector -  Schematic only __ Designed by va3iul

Metal Detector PLL 4046 Beachcomber -  Schematic only __ Designed by va3iul

Metal Detector Simple Circuit 3xBJT BFO -  Schematic only __ Designed by va3iul

Metal Detector Simple Circuit BFO -  Schematic only __ Designed by va3iul

Metal Detector Surfmaster Pi -  Schematic only __ Designed by va3iul

Metal Detector Toro -  Schematic only __ Designed by va3iul

Metal Detector uses Single IC -  12/18/97  EDN Design Ideas:  The circuit in Figure 1 protects a power bus from a load short within a guaranteed 2 µsec; a short could otherwise pull down the bus, affecting other loads.  The circuit also controls inrush current to bypass capacitors during hot-swap (hot insertion) , another situation in which bus voltage could otherwise experience a droop.  You can individually set the two current limits.  Power-on reset and logic controls allow complete µP interfacing. Design by Rachel and Steve Hageman, Hewlett-Packard, Santa Rosa, CA

Metal Detector using Difference Resonator -  This circuit can detect metallic conductors in its vicinity up to a range of 25 to 30 millimetres.  __ Electronics Projects for You

Metal Detector-A Pulse Induction Detector. Pulse-1 -  Hundreds of this Detector have been built with Very favourable Feedback __ Designed by G.L. Chemelec

Metal Detector-JF1OZL -  Schematic only __ Designed by va3iul

Metal Detector-Pulse-2 Induction Type Detector -  This is a Revised Version of the Pulse-1 above with Additional.  Controls for More Flexibility.  This Project is Definately Not Recommended for the Beginner __ Designed by G.L. Chemelec

Metal-AV a Pulse Induction Detector -  A PI Detector with Audiable & Visual indications of Targets.  Suitable for use on some Conveyor Belts.   __ Designed by G.L. Chemelec

Meter Adaptor With Symmetrical Input -  in contrast to an ordinary voltmeter, the input of an oscilloscope generally has one side (GND) connected to ground via the mains lead.  in certain situations this can be very problematic.  When the measuring probe is connected to a circuit that is also connected to ground, there is a chance that a short is introduced […]__ 

Meter/Data Acquisition Amplifier -  This simple amplifier is useful for boosting small signals up to about +-12 volts.  Many low-cost data acquisition devices have full-scale inputs of +- 10 volts which limits their sensitivity, and the negative part of the input range is usually wasted, cutting the available resolution in half.  This amplifier runs on 5 to 6 VDC and generates +-15 VDC to power a single, low-power op-amp.  The op-amp circuit includes an offset voltage capable of converting a single-ended positive input into a symmetrical bipolar output.  Current consumption is low enough to run the amplifier from a lantern battery for over a year of continuous duty (about 1 mA).  Switching to a micro-power op-amp will give decades from the same battery.  Using a battery allows many experiments to "float, " often eliminating ground loop problems encountered when hooking experiments directly to a computer.   __  Contact:  Charles Wenzel of Wenzel Associates, Inc.

Method offers fail-safe variable-reluctance sensors -  11/22/01 EDN Design Ideas:  Variable-reluctance sensors are preferred for industrial and automotive environments, because they sustain mechanical vibration and operation to 300°C.  in most applications, they sense a steel target that is part of a rotating assembly.  Because the unprocessed signal amplitude is proportional to target speed, a sensor whose signal-processing circuitry is designed for high speed cease Design by Phil Levya, Maxim Integrated Products, Sunnyvale, CA

Method simplifies testing high-Q Devices -  02/21/02 EDN Design Ideas:  The design of low-phase-noise oscillators requires careful attention to resonator unloaded Q.  in the construction of a low-phase-noise, high-frequency oscillator, the goal is to achieve an unloaded-Q figure greater than 400 in a reasonable package.  Also, you need to monitor the effect of the package and pc-board arrangement Design by Alan Victor, IBM Microelectronics, Research Triangle Park, NC

Method Tests Cables -  10/17/02 EDN Design Ideas:  MOSFET serves as ultrafast plate driver - Engineers have long known how to test a cable for continuity by simply connecting all conductors in series and checking with an ohmmeter.  This method is sometimes impractical, however, because it cannot check for short circuits.  The method shown in Figure 1 solves the short-circuit problem.  Connecting Design by Jim Keith, Bell-Mark Technologies, Dover, PA

Methods for Measuring Op Amp Settling Time -  Linear Technology AN10 __ Designed by Jim Williams - Jul 1st, 1985

Methods Measure Power Electronics’ Efficiency -  07/29/10 EDN Design Ideas:  Minimize the current drawn from the utility company.    Design by Liping Zheng, Calnetix, Yorba Linda, CA

Micro wind power with a Savonius rotor. Part 1. -  This wind turbine cost nothing virtually nothing to make and can produce enough power for small applications There are many situations where you might need a small amount of electricity, for instance running gate openers, safety __ Designed by Lance Turner

Micro wind power with a Savonius rotor. Part 2. -  Generating the power The generator I used was actually a large permanent magnet DC motor from an old vertical computer tape drive.  These are very robust, well built motors about the size of a large car starter motor.  They are simple __ Designed by Lance Turner

Microamps Monitor dual-supply batteries -  03/02/98 EDN Design Ideas:  NOTE:  File contains many circuits, please scroll to find this one  The low-power circuit in Figure 1  monitors two 9V batteries in a dual-supply configuration and turns on the Battery Low LED if either battery voltage drops below its limit.  it also provide as two shutdown signals you can use to turn off voltage regulators, such as Maxim's MAX663/664 positive and negative.   Design by Bruce Anderson, University of Wisconsin--Madison

Microcontroller Detects Pulses -  24-Jul-08 EDN Design Ideas:  A microcontroller detects output pulses in a device under test Design by Abel Raynus, Armatron International, Malden, MA

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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


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