PSU Power Supply Repair to component level, excessive high volt output. Walk & Talk fault analysis.

Here we have a HQ POWER PS1310 13.8v 10 Amp constant, 12 Amp Surge power supply for repair, the report is 25v coming out whihc is way high, obviously the issue will blow up any conneccted equipment. We confirm the fault, then progress to trace the fault, only to find a couple of resistors which have totally burned up with no identifying marks, furthermore we then find other issues with some transistors & voltage checks reveal the suspect components, we go thru the testing routine with isolating each component, Fortunatly the saving grace of this repair is that we manage to find the circuit diagram online which informs the value of the 2x resistors which had burned up, following replacement of componenets we then calibrate the output voltage to 13.8v DC. A load test at 6 Amps soak tests the power supply & we finally measure the output ripple to ensure the reserviour smooting capacitor is functining correctly acheiving a result of 6mV under load conditions, with a voltage drop 250mV.