|With a DVM (digital Volt Meter)|
I assume you don't have one.
I made the mistake of measuring the output, it was 20V DC.
I thought that was ok. I took it into my local pc repair shop. he
found it wasn't working.
I read the label on the psu, it was supposed to be 35 V DC.
It was an HP laptop,
UK MP's are thieving scumbags.
EU members are worse.