help with surf pi kit no sound

[alcartraz]

new batts u5 output 4.96 pin 5 of u6 - lead of new meter on ground + lead on pin 5 of u6 is -4.75 volts ? is that right

[Qiaozhi]

i got 5.22 volts on that pin

It should be -5V (or close to this value). Note: It should be a negative voltage.

[alcartraz]

i got 5.22 volts on that pin

[Qiaozhi]

the regulator is ok what do i test next ?

Check if the negative supply is working by measuring the voltage at pin 5 of U6.

[alcartraz]

the regulator is ok what do i test next ?

[alcartraz]

It appears that the previous meter you were using was faulty.
As the output should be 5V, I suggest replacing the regulator (U5). Then take the measurements again.

hi sorry people confusion set in i was testing q2 instead of u5 because q2 looks like the regulators i use in power supply i used to build in my job now tested u5 volts are good 11.4 going in 5 volts coming out i gess stress and trying to do many things all at the same time ?

[Qiaozhi]

right just tryed an old lcd multimeter i had kicking about i have got different readings pin 3 in 11.4 pin 2 0v pin1 out 10.5 that was measured - to ground + to pins on u5 now measured on pins pin 2 and pin 1 11.1 volts ?

It appears that the previous meter you were using was faulty.
As the output should be 5V, I suggest replacing the regulator (U5). Then take the measurements again.

[alcartraz]

right just tryed an old lcd multimeter i had kicking about i have got different readings pin 3 in 11.4 pin 2 0v pin1 out 10.5 that was measured - to ground + to pins on u5 now measured on pins pin 2 and pin 1 11.1 volts ?

[alcartraz]

17 to 18 volts fluctuating
input 11.37 all on the pins of u5

[Qiaozhi]

yes the silverdog long board from +bat to pin 2 15.55 volts continuity from pin 2 to batt - is good from - batt to pin 2 1.37 volts iam lost ??

OK, let's try a different approach.

What is the voltage between the GND and OUT pins of U5?
Put the meter probes directly on these pins.

[alcartraz]

Since pin 2 (middle pin) of the regulator should be at 0V, and you have the negative terminal of the voltmeter connected to 0V (I presume), then you may have a break in the ground somewhere. Try doing a continuity test from U5 pin 2 to the negative battery terminal. These two points should be connected together.

Think about it.
How can there be 1.41 volts on the regulator GND connection?

Is this a Siverdog (Surf 12 "ApB") long board PCB, or have you made it yourself?

yes the silverdog long board from +bat to pin 2 15.55 volts continuity from pin 2 to batt - is good from - batt to pin 2 1.37 volts iam lost ??

[Qiaozhi]

just had another look am i testing it right - test from multimeter to ground + to legs of u5 pin 3 11.7 bat volts same pin2 1.48 pin 1 10.48 and yes i need to put new bats in thank you for helping

Since pin 2 (middle pin) of the regulator should be at 0V, and you have the negative terminal of the voltmeter connected to 0V (I presume), then you may have a break in the ground somewhere. Try doing a continuity test from U5 pin 2 to the negative battery terminal. These two points should be connected together.

Think about it.
How can there be 1.41 volts on the regulator GND connection?

Is this a Siverdog (Surf 12 "ApB") long board PCB, or have you made it yourself?

[alcartraz]

just had another look am i testing it right - test from multimeter to ground + to legs of u5 pin 3 11.7 bat volts same pin2 1.48 pin 1 10.48 and yes i need to put new bats in thank you for helping

[alcartraz]

its in the same as all the pictures ive seen ? so maybe faulty

[Qiaozhi]

i got 11.48 volts from 8 aa batts going in i get 11.41 volts at the speaker the regulator first leg 11.48 middle leg 1.41 third leg 11.43 (r12 r13 r14 ) all have 0 volts ?

Firstly, your batteries are partly discharged, but they should be OK for testing.
Secondly, the regulator (U5) should have 11.48V at the input (pin 3), 0V on pin 2, and 5V at the output (pin 1). This is referring to the circuit diagram on Silverdog's website. Forget about R12, R13 and R14 for the moment. They're noting to do with the power supply. It looks to me like the regulator is either faulty, or you have it inserted incorrectly.