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Tester or Measurement (Instrument) Circuits

Test Equipment:  #'s - A        B - D        E - G
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Last Updated: October 24, 2017 02:55 PM
Circuits Designed by Dave Johnson, P.E. :

NMH/NiCd 6v Battery Tester -  I designed this circuit to test rechargeable six volt battery packs under constant current conditions.  As designed, the circuit applies a 10 amp load to the battery pack.  A heat sink must be used on the main power transistor . . . Hobby Circuit designed by David Johnson P.E.-December, 2004

NPN/PNP Transistor Tester -  I designed this circuit about 30 years ago and still use it from time to time.  it is powered from a 3v battery.  it makes a tone when the transistor tests good.  it can be used to determine device type (NPN or PNP) and the base, collector or emitter transist . . . Hobby Circuit designed by Dave Johnson P.E.-June, 2000

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Nano-Ampere Meter -  This circuit can measure currents down into the nano-ampere range.  it is useful when building, testing and experimenting with low-power circuits, especially those operating off batteries.  The circuit is built around commonly...__ Electronics Projects for You

Negative Ion Detector -  Figure 1 shows a schematic diagram of the ion Detector--a rather simple circuit consisting of three transistors (two PN2907 PNP, and a single PN2222 NPN type) , three resistors, one capacitor, an antenna, a mA meter, and an LED __ Designed by Vincent Vollono

Negative Ion Generator #2 -  The design of the Negative-ion Generator is fairly straightforward (see Fig.1). The circuit is a high voltage generator. it contains a standard 555 timer that's used to generate square-wave pulses. The pulses are applied to the base of the TiP120 NPN Darlington transistor. The Darlington provides sufficient current to the base of the 2N3055 power transistor to turn it on. Each. __ Designed by John Lovine

Negative Resistance Increases Inductor's -  03/30/95 EDN Design Ideas:  The circuit in Fig 1a synthesizes a negative resistance.  Putting this network in series with the inductor in Fig 1b increases the inductor's Q factor.  Fig 1b's filter was designed to attenuate a noise-power-ratio test signal's adjacent carriers of 200 kHz __ Circuit Design by Victor Koren, Orckit Communications Ltd, Tel Aviv, Israel

Negative-Ion Detector & Tester -  Figure 1 shows a schematic diagram of the ion Detector--a rather simple circuit consisting of three transistors (two PN2907 PNP, and a single PN2222 NPN type) , three resistors, one capacitor, an antenna, a mA meter, and an LED __ Designed by Vincent Vollono

Neon Bulb Quench Experiment -  it seems to be common knowledge that a NE-2 or similar neon lamp can be pressed into service as radiation (x-ray) detector.  But can a simple lamp serve as a low-level detector, possibly replacing a Geiger tube?  initial experiments with a variable voltage source and a NE-2 in a relaxation circuit consisting of a series resistor and a small capacitor across the lamp showed no sensitivity to x-rays and moderate sensitivity to light.  No attempt was made to use the lamp as an ion chamber or proportional detector but the volume is so tiny that success seems very unlikely.   __  Contact:  Charles Wenzel of Wenzel Associates, Inc.

Neon Lamp as Resistor -  Scroll to find this one.  it seems to be common knowledge that a NE-2 or similar neon lamp can be pressed into service as radiation (x-ray) detector.  But can a simple lamp serve as a low-level detector, possibly replacing a Geiger tube?initial __  Contact:  Charles Wenzel of Wenzel Associates, Inc.

Network Forms Digital to Impedance Converter -  03/14/96 EDN Design Ideas:  The circuit in Figure 1 resembles a capacitive-ladder (C-2C]D/A converter.  However, it does not provide conversion from a digital code to a voltage or current, but rather converts the digital code to a capacitor value.  The C-2C topology is well-suited __ Circuit Design by Alex Belousov, SMP Inc, Rego Park, NY

Network imitates thermocouples -  11/08/01  EDN Design Ideas:  Thermocouples find wideaspread use for temperature measurement in systems.  During system design or testing, you must observe the system's response at different temperatures.  However, it's inconvenient to heat a thermocouple every tim __ Circuit Design by Abel Raynus, Armatron International, Melrose, MA

Network Lead Tester -  This was designed for confirming the continuity and correct wiring of computer network leads, but it can be adapted to check any lead with up to 8 wires by using appropriate connectors.   __ Designed by John Hewes

Network RJ45 Cable Tester -  This is a multifunction RJ45 network cable tester.  it is the design of the network cable (RJ45) test, and telephone (RJ11).  it is cheap and easy to use.  it works for network, telephone, cable with RJ45 half “Registered Jack” plug immediately indicate whether a crossover network cable or straight, flashing a yellow or green __ Designed by Popescu Marian

Network Wiring Tester -  Like all its counterparts, this network wiring tester comprises two elements, a transmitter unit, powered and fitted at the network start point, and a receiver unit, passive, which can be moved around from socket to socket.  Each of these units carries eight LEDs, .  must register on this site __ Designed by Published in Elecktor July/Aug, 2010

New CCO Metal Detector -  Thomas Scarborough has designed a new embodiment of the CCO (Coil Coupled Operation) metal detector, a new genre which I invented in 2004.  I believe that this is the first IC design to appear on the internet (there is a transistor design on many websites, and IC designs were published by Elektor and EPE).  it took me just eight minutes to design this -- which illustrates the simplicity of the principle.  OBSERVATiON: On the surface of it, it may look like an iB (induction Balance) detector -- but it is not.  it works on the principle of the transformer coupled oscillator (TCO) , and requires an__  

New Lightning Detector -  Especially built for the beginner __  Contact:  Charles Wenzel of Wenzel Associates, Inc.

NiCad Sensor for Heli -  NIC ad Voltage Monitor for Rx   Circuit + Parts List + Notes __ Designed by Tony van Roon  VA3AVR

NMH/NiCd 6v Battery Tester -  I designed this circuit to test rechargeable six volt battery packs under constant current conditions.  As designed, the circuit applies a 10 amp load to the battery pack.  A heat sink must be used on the main power transistor . . . Hobby Circuit designed by David Johnson P.E.-December, 2004

Noise Meter -  Normally, sound intensity up to 30 dB is pleasant.  Above 80 dB, it becomes annoying.  And if it goes beyond 100 dB, it may affect your psychomotor performance, detracting your attention...__ Electronics Projects for You

Noise-Level Alarm -  Noise is a serious environmental problem that affects us in our daily life.  There is scientific evidence supporting that noise exposure can cause hearing loss, hypertension, heart disease, annoyance, sleep disturbance...__ Electronics Projects for You

Nokia 3310 LCD & PIC12F629 Thermometer -  Device with Nokia 3310 Lcd, Pic12F629 & DS18B20 temperature 1Wire sensor   - published in magazine "Svijet elektronike" Nr.58 (June / July 2006)  .   Author: ivica Novakovic __ Designed by © Ivica Novakovic

Nokia 7650 LCD Controller -  Despite nobody seems to own the appropriate documentation, it is possible to use the big cheap color LCD displays of the Nokia series 60 cell phones for home brew projects.  I don't even have the docs and it was a rough and painful way, but now it works__ 

Nominal 10 Watt Power Amplifier -  A Very Simple 12.5 Watt RMS Power Amplifier, into an 8 ohm load and with the op-amp driver.  This was the Maximum output before Clipping on the Oscilloscope, using an 8 Ohm Resistive load.   __ Designed by G.L. Chemelec

Noncontact Device tests power supplies -  03/01/01 EDN Design Ideas:  The probelike device in Figure 1 comes in handy as a quick go-no-go test for step-down power supplies.  You can build it using a very bright surface-mount LED and an inductor of the same type as in the power supply, which in this case is 100µH.  Placing this probe close to a working step-down power-supply coil lights the LED.   __ Circuit Design by Alberto Bitti

Non-Contact Power Monitor -  Here is a simple non-contact AC power monitor for home appliances and laboratory equipment that should remain continuously switched-on.  A fusefailure or power breakdown in the equipment going unnoticed may cause...__ Electronics Projects for You

Nonvolatile digital potentiometer gates logic signal -  09/03/07  EDN Design Ideas:  A novel use for digital potentiometers employs them as a logic gate that functions as soon as the system powers up __ Circuit Design by Reinhardt Wagner, Maxim Integrated Products, Ottobrunn, Germany

Not So Tiny Power Meter-Measures power consumption for entire apartment Not So Tiny Power Meter -  The Kill A Watt is an awesome product; it measures volts, amps and power factor of an individual appliance which can be used to calculate power, cost to run, etc.  it’s also quite hackable.  But I wanted something that would give me the same data for my whole apartment.  After some Googling, the best I could find was this project from picobay, but I didn’t want to invest in an expensive network iO platform __ Designed by Bill Porter

Novel isolates temperature sensor from its host -  08/03/06  EDN Design Ideas:  Temperature-to-period converter and transformer driver provide power and signal isolation __ Circuit Design by Alfredo H Saab and Tamer Mogannam, Maxim Integrated Products Inc, Sunnyvale, CA

Novel measurement eases battery-stack-cell Design -  01/10/08  EDN Design Ideas:  Automobiles, aircraft, marine vehicles, uninterruptible power supplies, and telecom hardware use series-connected battery stacks.  These stacks of individual cells may contain many units, potentially reaching hundreds of volts.  in such systems, it is desirable to accurately determine each individual cell’s voltage.  Obtaining this information in the presence of the high common-mode voltage that the battery stack generates is more difficult than you might suppose.   __ Circuit Design by Jim Williams, EDN's most revered contributor, passed away in June 2011 after a stroke.  He was 63.

Novel Q-meter -  08/27/13  EDN Design Ideas:  This highly unusual "cross-quad" circuit topology finds application measuring Q.  This instrument determines the Q (quality factor) of a resonant circuit, crystal, or resonator by measuring its series resistance at the resonance frequency.  The Q is linked to the series resistance by two simple equations (Rs is the series resistance, L and C the reactive elements and Fr their resonance frequency) : __ Circuit Design by Louis Vlemincq

Now That's Sneaky -  Turn on an appliance with the wave of your hand!  __ Contact Jameco Electronics

NPN/PNP Transistor Tester -  I designed this circuit about 30 years ago and still use it from time to time.  it is powered from a 3v battery.  it makes a tone when the transistor tests good.  it can be used to determine device type (NPN or PNP) and the base, collector or emitter transist . . . Hobby Circuit designed by Dave Johnson P.E.-June, 2000

NTC Thermistor Model -  (spice design)  __ Designed by Rick 

NTSC Test Signal Generator -  An accurate test signal generator for television calibration and measurements.   __ Designed by The Electronic Lives Manufacturing-presented Chan

Nuclear War Detector -  The circuit is similar to the earlier darlington circuits except that the output transistor is a MOSFET transistor like the BS170 or 2N7000 and the load is an LED with a built-in flasher circuit.  The circuit as shown will draw  __  Contact:  Charles Wenzel of Wenzel Associates, Inc.

Numeric Water-Level Indicator -  Most water-level indicators for water tanks are based upon the number of LEDs that glow to indicate the corresponding level of water in the container.  Here we present a digital version...__ Electronics Projects for You

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

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

 


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