So, over the weekend I built my first 555 based synth circuit.
Now, I want to add a control voltage at some point (was thinking about one of those Maplin Sequencers), but was planning on using a jack socket and cable to connect the two. Where would I wire the ground to?
Or, should I just use something like an RCA?
Use any kind of socket you like. Wire the ground to... ground!
Since the 555 oscillator circuit has its frequency controlled by a resistor rather than any sort of voltage control, you'll need to come up with some sort of converter. Probably a transistor to ground somewhere would do it.
Ground would make sense, wouldn't it?
As you may be able to tell, I was a little bit tired when I posted this last night!
I'd been reading this:
QuoteBy applying a voltage to the CONTROL VOLTAGE input, pin 5, you can alter the timing characteristics of the device. In the astable mode, the control voltage can be varied from 1.7 V to the power supply voltage, producing an output frequency which can be higher or lower than the frequency set by the R1, R2, C timing network.
and figured it'd work.
I might just experiment with a control voltage as-is, see what happens.
Below is the schematic for it (Minus a few teeny changes that don't make a difference), nicked from the Maplin site.
(http://img.photobucket.com/albums/v730/spann/synth.jpg)
Maybe I'll stick a video up (Of this and the other stuff I've built) soon.
Further question: Could anybody suggest a simple circuit to build in order to experiment with the output?