I made a Tonebender clone, positive ground and wired the DC jack following the GGG picture. When i plug the DC jack in i can hear hum.
I'm using a plastic DC jack (Small Bear) that doesn't touch the case. Any ideas what can cause the hum would be warmly appreciated ... :)
here is a picture of the situation
(http://www.hoho.cz/osobni/TB.jpg)
I made a Tonebender clone,
Looks good too from inside.
positive ground and wired the DC jack following the GGG picture.
The best kind if you have PNP transistors to use.
When i plug the DC jack in i can hear hum.
....And with battery it doesn't hum.
I'm using a plastic DC jack (Small Bear) that doesn't touch the case
Nice feature...
Any ideas what can cause the hum would be warmly appreciated
Simply put, the power supply.
See Spyder.
Try filter cap and little filter-helper resistor technique for today.
If the supply has ripple in it [often called "DC" by wallwart, is less than 'true DC', as in 'has AC signal' in it...called 'ripple'].
Try a DC voltage regulator.
...I'd say something else because I can't remember...7809 I think is the Neg Gnd. version and 7909 is the Pos Gnd Version...check those part #'s for compatibility for you first though.
thanks Peter,
i'll see what i can do :)