On Tue, Jun 18, 2013 at 12:30 AM, Christopher Brown <[email protected]>wrote:
> > On 6/17/13 6:50 PM, Orin Eman wrote: > > Since it doesn't seem to much mind 11V of 'ripple', I'm tempted to stick > an > > LM317L in there instead of the fussy zener/jfet/2n3904 circuit. I just > > have to go work out how much current it's drawing so I don't overheat the > > LM317L. I figure any slight drift from the LM317's voltage setting > > resistors isn't going to matter at all. I might just do this to add to > the > > knowledge base here. > > > > Orin. > > If the jfet is good (sounds like it is). > > Check the resisters on the PS board, IIRC it is the 510ohm one that is > the current limiter for the charging circuit. > Just did that - 530 ohms and the other 180 ohm series resistor was 183 ohms so I think I'm OK there. > > Replace the zener...pennies > Zeners are on order... > > Make sure the batteries are NiCd of about the right capacity (400 - > 1000mah). > The Batteries Plus NiCd cells are 750 mAH so they are right in there. > > The charge circuit is dead simple and should float the pack at 40 - 60ma. > > From you description it just sounds like the zener voltage is low, just > like both of mine. > Sure does. Seems OK at the moment with the two 1N4148s in series with the 'original' zener. Orin. _______________________________________________ volt-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
