Page 1 of 1

pin 8 / 4 both read 28V?

PostPosted: Tue May 19, 2009 4:34 pm
by mrniss
first power up test of a C84 sees pins 4 AND 8 of U1-U3 at 28 volts.

checked my meter 10 times, U1-3 are in right, U5/6 are in right, nothing is smoking but the readout is just wrong.

i hate my life. every single one of these i've made i've screwed something up somehow regardless of how careful i've been.

PostPosted: Wed May 20, 2009 2:44 pm
by tpryan
What voltage do you measure between pins 1 and 2 of J3? What about pins 3 and 2 of the same connector? J3 is the power connector. Pin 1 is closest to the front of the board, pin 6 closest to the XLR connectors. Make both voltage measurements with the black probe on pin 2. Next, make sure you're counting the pins on U1-U3 correctly. You can find the data sheet here: http://focus.ti.com/lit/ds/symlink/opa2604.pdf Again with the black probe at J3, pin 2, what voltages do you measure at U1-U3?

Let us know what you find.