10k trimmer

[aleeeeaaa]

I need to hook up a 10k trimmer in the schematic identified by the arrow. There are three terminals on the trimmer and i don't know which one is for what. I've enclosed the data sheet for this trimmer. Question is what are pins 1,2, and 3 for and how would they hook up in the schematic. I'm a new learner so if you could keep it simple for me i'll pick it up faster. Thanks
t

 

[kellys_eye]

Page 4 of the pdf shows which pin is which.

Pins 1 and 3 are either end of the resistive track, pin 2 is the 'wiper'.

On your schematic the 'wiper' is the pin connected to the +ve end of the 4.7μF capacitor. The other two connections can be either way around - if you find you want the volume to go in the 'opposite direction' (clockwise to go up) and find it's going up in the anti-clockwise direction just reverse them.

 

[duke37]

Is the input electrolytic and the output electrolytic the wrong way round?

 

[Audioguru]

The schematic is wrong:
1) The output transistors will be overloaded.
2) Two capacitors are shown with backwards polarity.
3) Yes, the speaker connects to the positive supply, not ground, so that the 1.3k resistor is bootstrapped for more output signal level.
I corrected it but I did not select suitable output transistors.

 

[(*steve*)]

Is the input electrolytic and the output electrolytic the wrong way round?

Looks that way.

And do you really want a (linear) trimpot as your volume control? Why not a normal (log) potentiometer?

 

[AnalogKid]

As is shown on pages 4, 5, 6, 7, 8, and 9 of the datasheet, pin 3 is the fully-clockwise end of the resistance element. Pin 1 is the fully counter-clockwise end. Pin 2 is the wiper. This is the standard for trimpots.

In your schematic, pin 3 goes to the 100 nF, pin 1 to GND, pin 2 to the 4.7 uF.

ak

 

[aleeeeaaa]

Thanks for the help. The audio amp is working perfectly.