Power Supply Protection
This article was supplied by John VK3HJQ
Power Supply Problem
I had a slight problem with my shack 13.8V 10A power supply, its output voltage went from 13.8v to 26v, “Oh No”, “Yes No” it took out the 723 voltage regulator, TIP31C & both 2N3055’s in the supply but luckily no radios.
Here is a simple CrowBar circuit to overcome this problem in the future, it’s an over voltage protection circuit for linear power supplies (not switch mode supplies) all it does is put a dead short on the output when the voltage goes over the set Zener voltage, it then blows the fuse on the supply saving your radio gear from smoking.
I have now completed this mod to all my Linear supplies 13.8V 10A, 13.8V 7.5A, 13.8V 30A.
Hope someone finds this useful.
John vk3hjq (01/01/2016)