LCR-T4 graphical transistor tester resistor capacitor ESR thyristor

LCR-T4 graphical multifunctional tester resistor+capacitor+diode inductor+transistor+MOSFET, etc
The LCD is a 12864 LCD display with backlight, and the backlight color is generally yellow green.
The power supply is a 9V stacked battery. If powered for a long time, two lithium batteries can be used to form an 8.4V battery pack for power supply.
function
*New startup voltage detection function added
*Automatically detect NPN and PNP transistors, N-channel and P-channel MOSFETs, diodes (including dual diodes), thyristors, transistors, resistors, capacitors, and other components,
*Automatically test the pins of the components and display them on the LCD screen
*The positive bias voltage of the emitter transistor can be determined by detecting the amplification factor and cardinality of transistors, MOSFET protection diodes, etc
*Measurement of gate threshold voltage and gate capacitance in MOSFETs
*The monitor uses a 12864 LCD (128 * 64 characters)
*High testing speed, validity period for component testing: within 2 seconds (except for larger capacitors, measuring large capacitors requires a longer time, and a measurement time of 1 minute is normal)
*One click operation, boot test, one click completion.
*Power consumption shutdown mode: less than 20 nA
*The automatic shutdown function can avoid unnecessary waste, save battery energy, and improve battery life.
1. Using ATmega8, ATmega168, or ATmega328 microcontrollers. (Our products use Atmega328 microcontroller)
2. 2x16 character LCD display results.
3. One click operation, automatically turning off the power.
4. The shutdown current is only 20nA and supports battery operation.
5. The low-cost version does not require a crystal oscillator and supports automatic power off. The ATmega168 or ATmega328 version of the 1.05k software uses sleep mode to reduce power consumption without measurement.
6. Automatic detection of PNP and NPN bipolar transistors, N and P channel MOSFETs, JFETs, diodes, dual diodes, thyristor thyristors.
7. Automatically detect pin layout.
8. Measure the current amplification factor of bipolar transistors and the threshold voltage of the emission junction.
9.   transistors can be identified by high threshold voltage and high current amplification factor.
10. Detection of protective diodes for bipolar transistors and MOSFETs.
11. Measure the threshold voltage and gate capacitance value of MOSFETs.
12. Supports the measurement and symbol display of two resistors, with up to four digits and units displayed. The displayed resistance symbol has connected tester probe numbers (1-3) at both ends. So the potentiometer can also measure. If the potentiometer is adjusted to one end, the tester cannot distinguish between the middle and two end pins.
13. The resolution of resistance measurement is 0.1 ohms, with a maximum measurement value of 50M ohms.
14. A capacitor can be detected and measured. Display the highest four digits and units. The value can range from 25pf (8MHz clock, 50pF @ 1MHz clock) to 100mF. The resolution can reach 1 pF (@ 8MHz clock).
15. It is possible to measure the equivalent series resistance (ESR) capacitance value of capacitors with a value above 2UF. The resolution is 0.01 ohms and displays two digit values. This feature requires at least 16K flash memory ATMEGA (ATmega168 or ATmega328).
16. Can display the correct direction symbol for two diodes. In addition, display positive pressure drop.
17. The LED detection is a diode, and the forward voltage drop is much higher than normal. The detection of dual light-emitting diodes is considered as dual diodes.
18. Zener diodes can be detected if the  breakdown voltage is below 4.5V. This will be displayed as two diodes, which can only be determined by voltage. The symbol of the probe surrounding the diode is the same. In this case, you can identify the true anode of the diode by a threshold voltage near 700mV!
19**** I understand this every year, I won't flip it anymore****
If there are more than 3 diode type parts detected, establish the number of diodes and display another failed message. This will only occur if the diode is connected to all three probes and at least one is a type diode. In this case, you should only connect two probes and start the measurement again, one after the other.
20. Measure the capacitance value of a single diode in the opposite direction. Bipolar transistors can also be measured if you connect the base to the collector or emitter.
21. Only one measurement is needed to find the connection of the entire bridge.
22. Capacitors with values below 25pf are usually undetectable, but can be connected in parallel with a diode or at least 25pf capacitor. In this case, you must subtract the part of the parallel capacitance value.
23. A resistance below 2100 ohms will measure inductance, and if your ATMEGA has at least 16K flash memory. The range will exceed 20H from 0:01mH, but the accuracy is not good. The measurement results only show a single component connection.
24. The testing time is about two seconds, and only capacitance and inductance measurements will require a longer time.
25. The software can set the number of measurements before the power is automatically turned off.
26. The built-in self check function and optional 50Hz signal check clock frequency accuracy and waiting for call (ATmega168 and ATmega328).
27. Measurement of internal resistance and zero offset self check capability of optional device calibration port output (ATmega168 and ATmega328). A 100nF to 20uF capacitor needs to be connected between pins 1 and 3 to compensate for the offset voltage of the comparator. This can reduce the measurement error of capacitors above 40uF. It was found that the gain of the internal reference measurement ADC was adjusted using the same capacitor internal calibration voltage reference voltage.
If the test current exceeds the maintenance current, the thyristor and bidirectional thyristor can be detected. But some semiconductor thyristors and bidirectional thyristors are better than what this tester can provide