Hi,
I’m having some trouble with the Super Simple Oscillator, I was wondering if anybody can see anything obviously wrong with it.
Wires
Orange: 12v +
Red: Audio +
Green: Audio -
Blue: 12v -
Working from this design without the CV yet:
I started off working from the design with two pots that has the 100k resistor connecting to the transistor pin (you can see the red dot where a moved it from).
I also tried flipping the capacitor because I thought I might have it around the wrong way, but I flipped it back.
Should the capacitor negative go into the LED positive? or to ground?
Is this schematic saying it should go between the transistor and LED positive? (is it effectively the same thing?) I don’t know 
It’s - to + on LED, which is between LED and transistor, which is not GND.
Thanks! I moved it one row over but still no luck, does have to be physically between the transistor and the LED?
Can you define “some trouble”. No sound at all, low volume, oscillating at fixed frequency no matter what, not happy with the potentiometer range, something else?
No sound at all and the LED doesn’t come on.
Noticing you labeled blue as -12v, and not ground. Just pointing that out in case you havent tried that. The cap was originally in the right place.
I actually thought it was the same thing. Here is a zoomed out photo of how the blue and other wires are connected
thx for the zoomed out version. B)
The stripboard diagram shows the cap going to ground, but the schematic shows it going to LED+.
There’s no -12V. Just +12V (orange) and ground (blue).
Check your power source. You should feed +12v and GND, not +12v and -12v. Can you give more details about what you are plugging intot he barrel jack socket?
Thats exactly what im trying to show! 
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Yeah I think that was my bad saying -12v when I meant ground. Here is a photo of the power supply I’m using. Should be centre positive at 12v right?
Have you checked there’s actually +12V going in? (With a multimeter?)
Looks good, do you get +12V on the board when you plug it in?
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Another thing to check is which way you put the led. In this schematic it’s used as a diode (all LEDs are diodes, that’s the d in led), which if it were the wrong way round, that would mess things up.
I just tried making this on a solderless breadboard. Good news is the LED lights up. However I haven’t gotten any sound out.
Given that it uses the transistor in an “off label” mode and the linked article http://www.kerrywong.com/2014/03/19/bjt-in-reverse-avalanche-mode/ says the 2N3904 breaks down at 12V, maybe it’s just on the edge of working and a different 2N3904 might work?
Or maybe I’ve got a mistake too. But not the LED!
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