4 oscillators on the wall... (fwd)

[Ken Stone]

Re power supplies

>> Use a real power supply. Running a 12 volt reg off 15 volts doesn't leave
>> enough "headroom" for decent 12 volt regulation.
>
>Really?  The 303 takes two, +12 and +5. Do I need two seperate power 
>supplies for each?  What about 4 +12 and +5 regs, one for each osc all 
>coming from my +15 power supply?  Anyway, thanks so much and I'll look 
>into each of your solutions.

I've looked up the data on 78xx series, assuming this is what you are using.
They require an input a minium of 2 volts above the output (including the
low part of any ripple). As you are connected to a regulated 15V source, It
should be okay.  Still, I don't like cascading regulators, because changes
in load on the last (5v reg) will affect both previous regulators and so on.

Separate regulators should cure the problem. I've seen it before on a servo
controller I had where two oscillators were interfering with each other
through the regulator's inability to provide the current needed by the
capacitor charge cycle, without changing its output voltage.

Ken
_______________________________________________________________________
Ken Stone   sasami at blaze.net.au  
Catgirl Paradise <http://www.anime.net/~kens/>
Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>