[Elecraft] Switching Supplies

[williamsonr at pbtcomm.net]

Pardon me if someone has already pointed this out (I have not followed the entire thread)- my past experience with linear supplies reveals an all too often failure mode of either shorted pass transistors or blown control chips (LM-723).  In either case the output voltage from the supply can rise to the unregulated DC filtered voltage (usually 20+ volts) and cook anything attached.  A fast and effective crowbar, if designed correctly, will clamp this voltage before it destroys your expensive equipment. With switchers my experience has been that one or more of the switching FETs or high speed diodes fail and the supply just dies (no output).  Which one would you rather have connected to your brand new K3 if it failed?

73
Rodger
N4NRW
counting down the day till the K3 arrival!