ampage
Tube Amps / Music Electronics
For current discussions, please visit Music Electronics Forum. The sunn still shines online!

ampage archive

Vintage threads from the first ten years

Search for:  Mode:  
previous: Aron On the memory man schematic: -- 10/10/1999 6:41 AM View Thread

Re: Need +15 volts from schematic

10/11/1999 2:36 AM
Don Symes
Re: Need +15 volts from schematic
Something to notice - the 4047, a CMOS logic part with VDD at pin 14 and VSS at pin 7 - is being run with VDD at GND, and VSS at some negative voltage (didn't notice if -15 or what). For some reason, they're running this circuit 'upside down'.  
 
I also failed to find where B1, B2, etc go. Is there another page or some stuff missing?  
 
Flipping the circuit over to run from a 'positive' supply shouldn't be too tough. The IC pins at GND go to +15, the pins at -15 go to gnd. The opamp and transistor biasing will have to be re-thought.  
 
Any particular reason for your concern?

 
Replies:
Aron I gave up. I understand how it work... -- 10/11/1999 3:19 AM
AMZ The circuit uses a negative voltage... -- 10/11/1999 9:34 AM