Choke Current

[alerich]

I'm sourcing a choke to install in a Peavey 5150. The choke that people commonly use is a Hammond 193D 8H @ 150ma. If the output tubes alone are drawing 150ma at idle (and mine are probably drawing a touch more) isn't a choke rated at 150ma too small? It would appear to me that the sum of all of the operating currents (sans heaters) would be flowing through the choke. If you leave the amp biased the way Peavey set it at the factory then you'd probably be ok since they only have the outputs pulling maybe 120ma total tops. I'm new to the choke installation thing and want to make sure I spec it adequately without wasting money/weight on overkill.

[bigsbybender]

The choke is typically placed after the plate supply, it works to smooth ripple for the Screen supply. Screens draw much less current than the plates so 150mA should be plenty for any tube a 5150 can take.

One example would be the 4 output tube Fender uses a Choke that is only rated at 90mA and I've never seen one fail to date.


j.

[alerich]

You are absolutely right. It didn't dawn on me that the choke comes after the point where the plate supply is. Thanks for waking me up! Much appreciated.