Archive for category: Tester Circuits

Capacitance Meter Using 555 Oscillator

Tester Circuits | By: Diagram mania

The frequency formula of 555 oscillator is popularly known. For a known resistors and capacitor, the frequency can be determined by a formula. From the math logic, if the frequency and the resistors are known, then an unknown capacitor could be determined by the inverse of the formula. Anyone who has a frequency counter are […]

Bulk Transistor Tester – An Easy Transistor Gain Classifier

Tester Circuits | By: Diagram mania

This transistor tester is very helpful if you need to sort bulk transistors. In  some market, if you know where to find it, sometimes you can get transistors sold in kg unit, not in single peaces unit. You can buy 1 kg of transistors with really cheap prices. Don’t be too happy right now because […]

How to build Transistor Tester

Tester Circuits | By: Diagram mania

Circuit diagram This simple circuit has helped me out on many occasions. It is able to check transistors, in the circuit, down to 40 ohms across the collector-base or base-emitter junctions. It can also check the output power transistors on amplifier circuits. Circuit operation is as follows. The 555 timer ( IC1 ) is set […]

Voltage-Current(V/I) Curve Tracer

Tester Circuits | By: Diagram mania

Voltage-Current curve tracer is very important tools for components ant circuits troubleshooting. This circuit need an oscilloscope with X-Y inputs to display the curve. This circuit provide adjustment for both peak-to-peak voltage and the current limiter. The peak-to-peak voltage selected using different voltage taps of the transformer, and the current limiter is selected by different […]

How to build XTal Tester

Tester Circuits | By: Diagram mania

Circuit diagram This is a simple XTal tester circuit. T1 and XTal have formed an oscillator. C1 and C2 are voltage divider for oscillator. if the XTal is safe, the oscillator will work well and its output voltage will be rectified by C3, C4, D1 and D2, then T2 will run and LED will light. […]

How to build IR Remote Control Tester

Tester Circuits | By: Diagram mania

Circuit diagram Notes: I have used a photodiode, SFH2030 as an infra red sensor. A MOSFET opamp, CA3140 is used in the differential mode to amplify the pulses of current from the photodiode. LED1 is an ordinary coloured led which will light when IR radiation is being received. The output of the opamp, pin 6 […]

RCV420: Single Chip Precision 4-20mA Current Loop Receiver

Tester Circuits | By: Diagram mania

RCV420 is a special function integrated circuit chip for 4-20mA current loop receiver. RCV420 provide complete 4-20mA to 0-5V conversion, with 0.1% overall accuracy, 86dB CMR, and ±40V common-mode input range. This IC chip is suitable for many applications: PROCESS CONTROL INDUSTRIAL CONTROL FACTORY AUTOMATION DATA ACQUISITION SCADA RTUs ESD MACHINE MONITORING Here is the […]

How to build Latching Continuity Tester

Tester Circuits | By: Diagram mania

"This Latching Continuity Tester can help you locate those difficult-to-find intermittent short and opens that other testers always seem to miss. It has been part of my workbench for many years and performs superb. I have solved many intermittend problem with this highly flexible unit." Latching Continuity TesterA continuity tester is a must on every […]

Pt100 RTD Current Loop Transmitter Using XTR105

Tester Circuits | By: Diagram mania

XTR105 is a 4-20mA current loop transmitter integrated circuit, with two precision current sources. The Instrumentation amplifier gain inside this chip can be configured for a wide range of temperature or pressure measurements. This integrated circuit chip provides current excitation for platinum RTD temperature sensors and bridges, instrumentation amplifiers, and current output circuitry on a […]

How to build Continuity Tester

Tester Circuits | By: Diagram mania

Circuit diagram Parts R1 1K R2 2K2 R3,R4 22K R5 2K7 R6,R7 56K R8 *See text C1,C2 22nF D1,D2 1N4148 Z1 8V2, 1/4 watt T1 2N3905 (PNP) T2,3,4,5 2N3904 (NPN) 9volt Alkaline battery suitable loudspeaker housing & probes An on-off switch is unnecessary. D1 is used when the battery is brand-new and giving over the […]