Inverting 0-5V output to -5-0V - Possible?

Anyone know how to add inverted outputs to a circuit?

I’ve made a circuit generates two 0-5v outputs. I’d like to add and two more outputs that give -5-0V.

Any ideas or pointers?

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Do you really mean “invert”? That is, 0V in gives 0V out and 5V in gives -5V out?

Or do you mean “offset”? That is, 0V in gives -5V out and 5V in gives 0V out?

You said “invert” but I take “-5 – 0V” to mean offset…

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Yeah, invert.

What I want is a flipped version of the outputs - 0V in gives 0V out and 5V in gives -5V out?.

Would be useful in your opinion?

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with R1 = R2… maybe 100k. Op amp is a TL07x for instance. Split supply (±12V).

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I’m learning everyday!

I didn’t realise it would be as simple as an inverting amplifier.

Super thanks :slight_smile:

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Probably add a 1k series resistor before the output jack, too.

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I’ve drafted a stripboard add-on. I’ll post if it works out.

I’m the meantime here’s the mock add-on panel to match my joystick panel.

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I like the name :slight_smile:

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I fancy a joystick controller but the kind I think would be most useful is non-centering. I have plenty of centering mini-joysticks and no idea where I would find something like the VCS-3’s built-in stick Eno could be seen using on the Old Grey Whistle Test in 1972. Do they make those any more?

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At least Intellijel seems to have a source:

Horstronic uses one too:

Thonk has one joystick left:

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These joysticks are made by Omter, they are the same as offered by Mammoth in the US. They are spring loaded but you can remove the springs pretty easily on one or both axis. — https://www.muffwiggler.com/forum/viewtopic.php?t=162500

Visually it resembles joysticks available from Adafruit https://www.adafruit.com/product/3102
and AliExpress https://www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20201006171608&SearchText=JH-D202X-R4

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i have a pair of mini Joystick and i keep out the inside spring to have on who don’t center come back, it’s an easy thing :grin:

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look at this

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Brilliant! Thanks for the advice, everybody.

Edit: I just remembered we have at least one smashed PS3 controller lying around. I like the look of the Adafruit design, too. I would like to have a good long stick part, ideally, and ability to swap different pots in would be nice.

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Thinking a bit more about this, I really just want a pair of pots and a two axis gimbal. The actuator doesn’t even have to be a joystick, just something to manipulate the gimbals in a more or less linear way. I could put the gimbals at the top and bottom of the stick, which is mechanically simpler. It would also be easier to dampen the movement. I’ll think about this.

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I took out the spring and removed the switch from $4 arduino thumbstick that I got from the local electronics shop. The stick stays is place after removing the spring and mounting it in a panel.

As noted by others, there are several how-tos and instructables online (with varying levels of destruction to the part!) if you choose that route. But I found this part pretty tricky - go slowly, gently and methodically.

The pros were that I got a cheap joystick controller module that replaces two knobs. The circuit is supersimple and gives you 0-5v on each output. The cost for my build was minimal as the joystick was cheaper than two pots and knobs and the other parts are cents.

Cons are the throw of the stick - I plan to extend the height of the stick with a chuppa-chup stick!

I’m not sure that changing pot values would make much difference. But there is lots of room for inverting the outputs, adding a 0-10v output, adding attenuators to the outputs etc.

Bottomline is that a $50 part would be better on all levels - but however you make it its a lot of fun😊

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Gyroscope. I think that may be worth a try. Modern gyros are tiny and quite sensitive, so it may be worth just coupling a gyro like MPU 6050 to an actuator of one’s choice. You get an accelerometer in the same package. It talks to the outside world using I2C protocol.

Has anybody tried this?

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Sam with it lightsaber…

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Here’s a working schematic for the CV joystick (module) with added inverted x/y outputs (for 0 to -5V)

Built it this afternoon and confirmed the output voltages with a multi-meter.

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Not too nice looking, but I’ve replaced the thumbstick with a piece of wire and some shrink tube to make a longer stick shaft.

Looks super sketchy but the extra throw gives a much nicer response.

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