Funny Tek 2445 scope problem

Tony Duell ard at p850ug1.demon.co.uk
Thu May 15 17:18:24 CDT 2008


> >    Also watch out for the middle lead of three-terminal (78xx/79xx)
> > voltage regulators...it's not unheard of to bring them up above
> > ground a bit with a voltage divider to make them operate at different
> > voltages.
> 
> The _middle_ lead is not ground on the 79xx parts!

The 'rule' I remember, at least for TO92 and TO220 packaged 78xx/79xx is 
that the middle pin is the most -ve. Therefore it's common on the +ve 
ones (78xx) and input o nthe -ve (79xx) series.

-tony



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