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Tester or Measurement (Instrument) Circuits

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Last Updated: November 22, 2021 03:00 PM

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

PAL/NTSC Video Text Generator -  Perfect low cost solution for: * New video security installations * SSTV transmitters * Amateur video * Existing installed security installations * Scientific experimentation monitoring * and any other application that needs the time and date recorded on an image! .  __ 

Palace TE-16A transitorized Test Oscillator manual w/schematic  -  Circuit Only __ Designed by Palace TE

Panel Frequency Meter -  Here’s a simple panel frequency meter to measure the frequency of 230V AC mains.  When you connect it to the 230V AC line, the display shows the line frequency.  Generally, the...__ Electronics Projects for You

Panel Mounting Radio Frequency Counter -  This very tiny frequency counter was built to fit inside the front panel of a radio tranceiver.  it now occupies pride of place in the front panel of my HF Receiver, alongside my panel mounting clock.  One of the switches is used to switch the counter on and off, the other sets the display resolution.  The two choices for display resolution are 1Hz, which will read one measurement per second, or 10Hz, which will read 10 measurements per second. __ Designed by Hans Summers

Panoramic Spectrum Analyzer for HF Receivers-WA6NCX -  Schematic only __ Designed by va3iul

Parallel port logic analyzer -  As I don't have an oscilloscope yet so I needed a cheap way to analyze some signals, I decided to build a simple logic analyzer to use with PC's parallel port.  I used the schematic from here as a base and made my own improvements to it so it would__ 

Parallel port provides high-resolution temperature sensing -  10/03/02 EDN Design Ideas:  Simple tester checks LCDs - High-resolution temperature sensing at low cost is possible using only one chip attached to the PC's parallel port (Figure 1).  The Dallas Semiconductor (www.dalsemi.com] DS1722 digital thermometer allows measurement resolution as fine as 0.0625°C in digital form and with linear response.  The accuracy specification is only 2°C, but you can improve this figure by careful calibration Design by Martin Connors and Mike Foote, Athabasca University, AB, Canada

Paralleling Rms Converters Speeds Settling -  05/11/94 EDN Design Ideas:  An rms-to-dc converter requires an output lowpass filter, which sometimes leads to overly long settling times.  Paralleling two converters reduces the circuit's settling time signal without increasing conversion errors Fig 1.  The circuit in Fig 1 monitors 50-Hz mains Design by Bernard Courtiol, Cegelec Soprano, Vaulx Milieu, France

Park Aid -  Three LEDs signal bumper-barrier distance; infra-red operation, indoor use __ Contact Flavio Dellepiane, fladello @ tin.it

Park-Aid Modification -  Three-step beeps signal bumper-barrier distance; infra-red operation, indoor use __ Contact Flavio Dellepiane, fladello @ tin.it

Parking aid senses distance to rear of vehicle -  The circuit is drawn with PCB 123 which you can download for free from http://www.pcb123.com    As a keen cyclist I am always looking for ways to be seen at night.  I wanted something that was a novelty and would catch the motorists eye.  So looking around at my fellow cyclists rear lights, I came up with the idea of ‘NiTE-RiDER’.  NiNE extra bright LED’s running from left to right and right to left continuously.  it could be constructed with red LEDs for use on the rear of the bike or white LED’s for an extra eye catcher on the front of the bike. __ Designed by Paul Hill

PC Games Port Tester -  So your joystick dosen't work? is it the games port, a software problem or the joystick itself? This simple device will tell you if the games port is OK.__ SiliconChip

PC hardware Monitor reports the weather -  01/18/01 EDN Design Ideas:  You usually use PC hardware monitors to keep a close eye on powersupply voltage levels, the speed of system cooling fans, and even the temperature of the CPUPDF has several circuits, scroll down.    Design by Sean Gilmour, Analog Devices, Limerick Ireland

PC Power Monitor -  it clips into your PC and has three LED bargraphs to indicate the health of the PC's supply rails.__ SiliconChip

PC thermometer using PC game Joystick Port -  A method of measuring temperature using the PC Game port.   Display is via the program dialog or in the System tray.  V2.2.5 supports timed FTP to a web server __ Designed by andrew  AT AndysWorld

PCB Drill Speed Controller with 555 -  Described here is a simple, inexpensive and useful circuit for electronics hobbyists.  The circuit is nothing but a PCB drill speed controller, which can be used to control the speed of any 12VDC small pcb drilling units.  Such portable units are now widely available, and even a hobbyist can make it without too much difficulty.   __ Designed by T.K. Hareendran

PCB for Dan Fink's Anemometer -  Homemake Easter Egg Anemometer __ Designed by Dan Fink

PCB Trace Width Calculator -  This Javascript web calculator calculates the trace width for printed circuit boards based on a curve fit to iPC-2221 (formerly iPC-D-275).  Also see the via calculator.   __ Designed by Brad Suppanz

PCB VSWR Bridge -  When building HF/VHF equipment it is often required to add a VSWR sensing circuit into the rig.  Commercial bridges are often quite bulky and designed around a bulky sensor.  They often require the metal box as an earth path between the input and output. __ Designed by Harry Lythall-SM0VPO

PC-Based Configurable Filter Uses No Digital Potentiometers -  01/23/03 EDN Design Ideas:  Fleapower flasher draws less than 50 µA - Modern instrumentation requires digital control signals.  These signals come from a central microprocessor or, in modern context, the popular parallel or serial PC ports.  in recent times, digital potentiometers have eliminated the hassles from this interface for the analog section.  Designers can replace the resistors of the analog design with digital potentiometers, thus providing the necessary Design by Saurav Gupta and Tejinder Singh, New Delhi, India

PC-Based DC Motor Speed Controller -  This circuit allows you to control the speed of a DC motor (in eight levels) from your PC’s parallel port.  The PC uses a software program to control the speed of...__ Electronics Projects for You

PC-Based heart rate Monitor using Arduino & Easy Pulse sensor -  The heart rate, also referred to as pulse rate, has been recognized as a vital sign since the beginning of medicine, and it is directly related to a person’s cadiovascular health.  Today, we are going to make a PC-based heart rate monitor system using an Arduino board and Easy Pulse V1.1 sensor.__ 

PC's IRQ7 & INT1Ch measure currents, charges -  10/12/00 EDN Design Ideas:  Figure 1 shows that you can use just two interrupts (iRQ7 and iNT1Ch] of a PC and a few inexpensive components to make simultaneous measurements of two electrical quantities.  Two examples are low currents and their associated charges, parameters important in ion implanters.   PDF contains multiple circuits - scroll to find this circuit[K Suresh, iGCAR, Tamil Nadu, india] Design by K Suresh, IGCAR, Tamil Nadu, India

PC's parallel port to program a clock source -  12/07/04 EDN Design Ideas:  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 by William Grill, Honeywell BRGA, Lenexa, KS

PC's serial port controls programmable sine-wave generator -  09/01/06 EDN Design Ideas:  Audio-frequency signal source uses few components Design by Yongping Xia

PeacefaIR PZEM-021 energy meter hacked SPI to SERIAL output AVR mega88 -  The Peacefair PZEM-021 energy meter is very popular and super cheap at ebay
the unit is very good and usefull for all sorts of projects and to be used when working with mains powered electronics. __ Designed by Thomas Scherrer OZ2CPU

Peak Detector Lowers Frequency-Dependent Error -  01/18/96 EDN Design Ideas:  The classic peak detector in Figure 1a  lacks the necessary performance to drive an audio-level indicator.  Because of the amplifier’s slew-rate limitations, this circuit suffers a reduction in detected output with increasing frequency.  The amplifier acts Design by Harry Boling III, RF Monolithics, Dallas, TX

Peak Detector Maximizes CCD-Sensor Range -  08/15/96 EDN Design Ideas:  To get the maximum performance from an optical instrument that uses a laser source and a CCD linear-array sensor (Figure 1a], an A/D converter should perform over the maximum possible range.  You can maximize this range by stretching the upper reference of the flash A/D converter to coincide with the highest lit pixel in the CCD array.  Most flash A/D converters Design by Giovanni Romeo, Istituto Nazionale di Geofisica, Rome, Italy

Peak Detector Operates From Single Supply -  05/12/94 EDN Design Ideas:  The circuit in Fig 1  can detect the peak of either positive or negative inputs, yet it operates from a single supply.  The circuit uses two unity-gain amplifiers to monitor the input signal, one an inverting amplifier and the other a noninverting amplifier.  A typical application is driving a VU meter Design by Chester Simpson, National Semiconductor, Santa Clara, CA

Peak Detectors Gain in Speed & Performance -  DN61 Design Notes__ Linear Technology/Analog Devices

Peak Level Monitor -  Measurement of peak level is useful while testing an amplifier or a similar device.  it is handy while testing a logic circuit, as it can pick up a high transient pulse...__ Electronics Projects for You

Peak-To-Peak Monitor Uses No Op Amp -  11/23/94 EDN Design Ideas:  The peak-to-peak monitor in Fig 1 uses three identical transistors and three identical resistors rather than a handful of op amps and their associated components.  The circuit measures voltages up to ±2V p-p Design by Phil Harvey, Technology Integration Inc, Bedford, MA

Pedometer -  Pedometer has a range of 9.950 meters with2-digits.  Slip it in pants pocket for walking and jogging __ Contact Flavio Dellepiane, fladello @ tin.it

Pellistors -  Pellistors employ catalytic combustion to measure combustible gases or vapors in air up to the Lower Explosive Limit (LEL) * of the gas.  The standard sensor consists of a matched pair of elements, typically referred to as a detector and compensator (reference element).  The detector__ City Technology, Ltd

Peltier Thermopile Cloud Sensor -  18-Apr-14 -Design News:   Peltier, or Thermoelectric, coolers are a fairly modern device, but the concept of generating electricity with dissimilar metals goes back to Seebeck and Peltier's work in the 1800s.  Modern devices use alternating P and N semiconductor junctions to pump heat from one side of the device to the other __  Gadget Freak-Case #253

Perform PSRR testing with analyzers having no dc-bias ports -  07/19/07 EDN Design Ideas:  A simple test setup sums the output of an analyzer and a dc bias to test the RSRR of a DUT Design by David Karpaty, Analog Devices, Wilmington, MA

Performance Verification of Low Noise Low Dropout Regulators -  AN83 in an increasing trend, telecommunications, networking, audio and instrumentation require low noise power supplies.  in particular, there is interest in low noise, low dropout linear regulators (LDO).  Establishing and specifying LDO dropout performance is relatively easy to do.  Verifying that a regulator meets dropout specification is__ Linear Technology/Analog Devices

Periodically on-off Mosquito repellent -  Here is a circuit that automatically switches on and off the mosquito repellent after preset time interval, thus controlling the release of toxic vapours into the room.  __ Electronics Projects for You

Person Detector -  This is a circuit thich I originally included in my book, 22 Tested Transistor Projects, published by BabanI Press in 1976 (iSBN 0 900162 63 S).  it is one I had great fun with.  it uses the PUT Complimentary Feedback Pair as a sensitive detector of changing electric fields to switch on an oscillator and make a noise.  it is so sensitive that it can be difficult to get it working on a test bench because of all the electric fields, but put it on a table and leave it.   __ Designed by Richard Torrens

Personal Network Analyzer -  An instrumentation project that uses a PIC  for control. (Featured in QST)  __ Designed by Steve Hagerman

Personal Noise Source for Tinnitus Sufferers -  Portable device generates soothing pink or white noise to mask out unwanted sounds.__ SiliconChip

Phase / Impedance matched Pogo Pin to DUT fixture board-for high speed production ATE tester -  Many ATE test systems use Pogo Pins to connect the load boards to the DUT boards.  These boards are typically outsourced to people who have lot's of digital experience but very little RF experience.  This simple board was originally designed by one of those places.  Since the designed had no RF experience they did not understand what kind of structure to use for the 50  __ Designed by Steve Hageman

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

Phase Noise Measurements -  The phase noise of low noise oscillators and signal sources is usually determined by measuring the audio noise voltage at the output of the phase comparator in a phase-locked loop.  The phase comparator is typically a low noise doubly-balanced mixer with a phase slope from a few tenths of a volt per radian to a few volts per radian.  The low __  Contact:  Charles Wenzel of Wenzel Associates, Inc.

Philips GM 3150 oscilloscope pictures, brochure, schematic -  vintage television (schematic)  __ Designed by Frank Pocnet

Philips GM 3152 oscilloscope pictures, brochure, schematic -  vintage television (schematic)  __ Designed by Frank Pocnet

Philips GM 5654 oscilloscope manual w/schematic (nl) -  vintage television (schematic)  __ Designed by Frank Pocnet

Philips GM 5655/01 oscilloscope manual w/schematic (nl) -  vintage television (schematic)  __ Designed by Frank Pocnet

Philips GM 6012 AF Millivoltmeter manual w/schematic -  vintage television (schematic)  __ Designed by Frank Pocnet

Philips GM 655/03 oscilloscope manual w/schematic (nl) -  vintage television (schematic)  __ Designed by Frank Pocnet

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

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