When connecting your USBasp programmer, a common mistake is to power the whole device through the programmer, which can lead to verification errors. It is often more reliable to and not provide power through the programmer. You would then connect only the data lines (MISO, MOSI, SCK, RESET) and the ground (GND). This approach is particularly recommended for older or clone devices with unstable VCC lines.
The absolute master repository for all clone testers. Link: SVN Repository for TransistorTester lcr t7 firmware link
You will likely find that you cannot read the original firmware. When connecting your USBasp programmer, a common mistake