Item Type: Transistor Tester Material: PCB Model: GM328A Input Voltage: DC5V Type C Power Supply Working Voltage: About 30mA Plug In Measurement: Support Patch Measurement: Support Negative With Power: Without Battery Control Method: Encoder Display Screen: 1.77 Inch TFT Color Screen . Rotating coding switch has 6 operation methods: short press, long press, left rotation, right rotation, press and hold left rotation, press and hold right rotation. Press it in the off state to turn on the power and start testing. If the device is not detected after one test. Press and hold the switch or turn the switch left or right to enter the function menu. Once you enter the function menu, you can select the left and right switches above or below the menu item. To enter a function item, press the switch briefly. When you need to exit a function, press and hold the switch. 1. Tester calibration is used to eliminate the errors of its own components and make the final test results more accurate. Calibration is divided into quick calibration and full function calibration. 2. Quick calibration operation method: use the wire to short three test points TP1, TP2, TP3, then press the test button, while observing the screen. The screen color will change to white on black and the message "Selftest mode...?" will appear. will appear, press the test key to enter the fast calibration process; if the prompt "Self test mode...?" appears, if no key is pressed within 2 seconds, the normal test process will be entered, and the wire resistance values of the shorted TP1, TP2 and TP3 test points will be displayed at the end. After entering the quick calibration process, some data will appear on the screen, regardless. Wait until a flashing string appears on the screen "Isolating Probe!" After that, remove the shorted TP1, TP2 and TP3 wires. Wait until the "Test End" string appears on the screen and the quick calibration is complete. For the first calibration, use the full function calibration mode. 3. Full function calibration requires access from the function menu and an additional 220nf capacitor. Full function calibration performs a more comprehensive calibration process and takes longer. Once in the function menu, turn the test button to the "Selftest" menu item and press the test button again to enter the full function calibration process. The flashing string "short Probes!" appears on the screen first, and then, like a quick calibration, you short the three test points with wires and wait for the calibration process. The flashing string "Isolated Probes!" appears on the screen When the string "1 - | | - 3>100nf" appears on the screen, the prepared 220nf capacitors are installed on the test points TP1 and TP3. Wait until the screen prompts "Test End" to complete the fully functional calibration process.