When I set this at 9.91v, then attach a load, it drops to 9.72v. That's almost 2%.
My supply is a 7.5A switcher, taken from old laptop. I also used
a 10A transformer/rectifier/cap as a supply. Same problem.
I am using thick, short wires, & I am taking my voltage readings
directly from the output terminal of the LM338K (the case) before the breadboard,
so as to eliminate voltage drop thru the limited current handling
of those tiny little holes/terminals of my breadboard. I am using a
LM338K, old stock, Linear Technology device, of which
I have several. It's from Hanford, WA, circa 1980's, surplus. Not China.
I am using a large copper cpu heatsink.
Anyway, I am using a 12v, 50w halogen as my load. I am at almost 2%
of fluctuation under load from initial set point. Is this normal?
I thought these LM317/350/338 regulators were tighter than this?
My supply is a 7.5A switcher, taken from old laptop. I also used
a 10A transformer/rectifier/cap as a supply. Same problem.
I am using thick, short wires, & I am taking my voltage readings
directly from the output terminal of the LM338K (the case) before the breadboard,
so as to eliminate voltage drop thru the limited current handling
of those tiny little holes/terminals of my breadboard. I am using a
LM338K, old stock, Linear Technology device, of which
I have several. It's from Hanford, WA, circa 1980's, surplus. Not China.
I am using a large copper cpu heatsink.
Anyway, I am using a 12v, 50w halogen as my load. I am at almost 2%
of fluctuation under load from initial set point. Is this normal?
I thought these LM317/350/338 regulators were tighter than this?
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