Hi,

I would like to make a sine wave generator as described here:
http://www.bobsdata.com/audio_sine_wave_generator/index.html
What I dont understand from the schematic is how the dual potmeter (R5) is connected. Are the 3rd terminals of each channel of the potmeter connected to each other via the dashed line or something like that?

 

no they are two separate potentiometers, connected mechanically so they both move together.

http://www.maplin.co.uk/p/omeg-4k7-andohm-linear-dual-gang-potentiometer-fw84f

 

No. The third terminals are left disconnected. The dashed line indicates that R5 is a dual pot.

 

What is shown is called a "ganged pair of pots" or "ganged pots". There is no electrical connection between the pots. The purpose of the dashed lines is to indicate that they share a common shaft. The two pots are mounted on the same shaft so that the control knob turns both pots equally at the same time.

A common usage of ganged pots is in the volume and tone controls of stereo audio amplifiers.

 

Ah, of course! Thank you