Current limiting stopped working on a power supply

Question

I have an old power supply (Tesla BS554) and all of a sudden the adjustable current limiter stopped working. The supply is designed to limit the output current up to 1 A, but I am measuring short-circuit current of approx. 3,5 A, no matter the position of adjustment potentiometer.

Output voltage can still be regulated as normal.

I know for sure the potentiometer is not faulty (I have tested). Something must have happened to the circuitry.

Based of the schematics, do you see any spots where I can perform measurements to localize the faulty component?

Answer 1

I don't necessarily understand the schematic, but check E14 and then E25 for a short. Your symptom is consistent with a current-limiting BJT that has had a short.