PWM Layout question

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I am laying out the PWM on a perfboard and I noticed that there was a resistor that is not in the schem.

R1 seems to bridge between the ground and the input, whereas in the schem, that resistor is not there.

What would be the reason for this? I am assuming it is not a mistake, but I am wondering what it  does.

[bagudan]

I think it´s a pull-down-resistor, to prevent "pops" when switching on and off....

[earthtonesaudio]

...and it's completely unnecessary, as there is no input coupling cap and pin 3 of the '386 is already referenced to ground through a 50k resistor internally.

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I think an input coupling cap has been added as well, no? C4?

(edit: I notice the schem isn't showing up now, must be a geocities thing)

[earthtonesaudio]

Ah, yep.  I was looking at the schematic and didn't notice that on the layout.  With the added cap, the added resistor then makes sense.