Voltage regulators in "series"

**broken link removed**
7905 and 7805
(-5V) and (+5V)

I bought a old Toshiba T2200sx laptop and found this inside. These are voltage regulators but how does this thing work? :?

Thanks.

Well, if it's really connected like that, you will get +5V from the 7805 and, since the 7905 is referenced to +5V, its output wiil be approximately zero volts. It's like GND, but it will only sink current. I can't imagine why this would be done. Are you sure it is connected like that?

Yes it is connected like this.
And I think you are right.
This is propably a fake ground.
Thanks for the reply :wink: