[Amps] Small transformer evaluation

[Bill, W6WRT]

ORIGINAL MESSAGE: 
On Sun, 2 Sep 2012 11:53:20 -0400, Carl wrote:

>A resistor from screen pin to ground will take care of the negative current 
>by supplying a constant bleed. Calculate what is needed based upon the 
>actual negative current without the regulator in place. If you have 
>sufficient PS overhead you dont have to be exact.

REPLY: 
What Carl says is true if you are using a transistor regulator which can not
supply negative current. 

If you have a simple zener (or two) you don't need a separate bleeder. The
zener(s) will supply the negative current. 

Remember - When the zener(s)is supplying negative current it is also supplying
positive current through the feed resistor, so be sure the zener(s) is rated to
handle both the positive idle current and any possible negative current at the
same time. 

73, Bill W6WRT