[sdiy] Help trouble shooting mfos echo rockit

[Tim Stinchcombe]

Hi JoeF,

These three readings show that your 13700 isn't getting a proper negative supply:

> 1.25-1
> 0-6
> 1.25-16

(i.e. pin 6 is at ground, and this is reflected in the pin 1 & 16 readings too).

>From the pin 11 reading I am assuming you are trying to run off +9, -9V split supplies:

> 9.14-11

Thus you should see -9V at pin 6, and approx. -9+1.2 = -7.8V at both pin 1 and 16.

So check your negative supply rail is getting around the board properly.

Tim
__________________________________________________________
Tim Stinchcombe 

Cheltenham, Glos, UK
email: tim102 at timstinchcombe.co.uk
www.timstinchcombe.co.uk