Controlling the volume on a speaker connected to an 8M

[Andres Rodriguez]

The Picaxe Manual 3 shows the connection of a speaker but there is no mention of limitations in speaker size (Ohms?) nor is there any mention of volume control.
I would like to use a 1.5 inch 8 ohm speaker and be able to control the volume.

 

[Steve Joblin]

You can't control volume unless you use some type of amplier circuit. You can easily connect an 8 ohm speaker to a PICAXE. connect the output pin through a current limiting 330 ohm resistor to the + side of the speaker and the - side of the speaker to ground.

 

[Michael 2727]

You can control the volume if you use a low Ohm Pot.
The pot must be on the speaker side of the 330 Ohm
resistor and in parallel with the speaker.
It shorts out the output signal basically.

NOTE: Most Pots can only handle 50mA or so
before they burn up the carbon track, the 330 Ohm
resistor should limit the current to 15mA @5V supply.

It's not the most elegant way of doing things but
will work.

 

[Jaguarjoe]

Just use a resistor larger than 330 ohms to limit the signal going to the speaker. Or put a rheostat in series with that 330 ohm resistor to act as a volume control.