New to circuit bending

I’m new to circuit bending video equipment, and recently purchased a video enhancer that I am looking to circuit bend. If anyone has any informational resources it would be greatly appreciated.

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here they are welcome! I’ve only done circuit bending with audio stuff I bet it is fun with video

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I dont think there are many resources out there that specifically pertain to bending video devices but any resources you can find on the principles of audio bending should apply with some differences. An amazing resource into the world of bending comes from Reed Ghazala who has a great book on the subject. Id highly suggest pouring over his website as a good starting point.

Audio bending is very freeform. Its all usually low voltage battery operated circuits that are incredibly forgiving. With video you often are dealing with mains AC voltage and far more sensitive circuits.

The first thing that I do when I get a new device to bend is I lookup all of the ICs (black chips with parrallel groups of legs). The most important things to note is the power on these chips. Any positive or negative rails being fed to a chip should be avoided. There are no bends to be found there just puffs of magick smoke while the angry pixies escape to freedom. From there its all trying combinations of crossing pins, pulling pins to ground, adding resistance, filtering with capacitance, etc. It can get far more advanced from there but that is a great starting point.

You can find bends all over a board but you need to be able to identify where the power is on the board so you can avoid that. Most of your work should be done with some kind of test lead with a low value resistor in line to keep you from accidentally dumping a load of power into whatever points youre testing.

Where you go from there depends on what you want. Are you just looking for a couple cool effects? Or do you want to squeeze every last bit out of that hardware that you can? If youre looking for the latter then documentation will be your new best friend. I have a notebook dedicated to bend notes. Everytime I find anything worth writing down I write down the paths and give it a rating so I know if its worth including in the final configuration.

Bending can be alot of fun but it can also be very tedious if you want to really push the hardware.

If you have any more questions feel free to ask.

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Hi, new to the forum and this is the exact post I was looking for!

You mention looking up all the ICs to make sure not to connect power to things that won’t like it very much. As a complete newbie to electronics (have done basic DIY circuit builds with a soldering iron and step by steps, but that’s about it), what would be the best route to avoid blowing chips/learning how to identify what the chips are and where the power rails are?

Also, is 12V DC a safer option to bend? (I’m in the UK and there are a tonne of 12V DC VideoTech devices here which look like great starting points as they’re low cost) or is it still a ‘health risk’ as it’s mains?

Hiya :smiley:

On identifying the chips. You need to disassemble the device usually to get access to the front of the PCB (which is usually on the front of the device - underneath the bit where the buttons and knobs etc attach to), rather than the back. At least on all the Video Tech devices I’ve found. You look at them, note down the number and then look up the data sheets with that number. They should tell you what pins are power and ground. I tend to avoid both of them.

To be honest I am pretty lazy and can’t be arsed taking all the sliders and knobs and things off, so just bend from the back blindly. With the Video Tech stuff - as you mentioned - it’s so cheap and fairly low power (up to 12v for the enhancers) that it’s not a big deal if it blows a chip. The 9v ones are best as you can run them from a battery with a convertor rather than having to plug into the wall (in the rare situation something goes wrong with the PSU), but again… eh I haven’t bothered with that. The ones you want to watch out for really are the direct AC powered things that take AC power into the device. There will be a transformer in there which steps it down to a safer DC voltage, but if you are unsure and get over-exuberant, then you could run the risk of touching that which would be. Bad.

With the Video Tech stuff, the one thing to watch also is that the cases are often steel which is a NIGHTMARE to drill. Try out the VEC1070 as I am fairly sure it has a plastic casing. You’ll thank me later!

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Thanks for the detailed response! Totally makes sense now, I watched some videos (one was yours I believe with the titler, sick btw) and realise now it was just the back of the PCB, which threw me as I wondered how you could identify anything haha)

So, if a chip blows, is that kinda ‘game-over’ for that piece of kit? Or does it mean it just works…differently?

You mention running from a battery with a converter, what exactly is this?

Funnily enough, it’s the VEC1070 that i’ve got! So that’s a good start!
This is sounding more achievable now. My main concern is not getting an unexpected ‘shock’.

Yeah, the front of the PCB is on the other side, and you can see all the chips with their numbering etc. In my videos I am using the rear solder points (which is where you should bend really), but I don’t check the ICs unless I am feeling fruity.

If the chip blows, it depends on what the function of that chip was. They are rarely inessential though, and so the device will - generally speaking - be fucked. It won’t display video, or some other crucial feature will be dead. At that point you can either try replacing the chip (pain in the arse), or get another cheap one to mod and avoid doing whatever you did that last time to blow it up again.

For the battery clip… Search for battery power DC clip. You basically clip it onto a 9v square battery and then plug it into the synth’s DC port (pay attention to the polarity).

On the shocks… Use insulated crocodile clips so your skin is not in contact with the circuit. Do not lick your fingers and use them to test bend points. Other people do that for audio bends, but it is a bad idea with video stuff (and honestly in general I’m not a fan of that approach at all). Note: I am nowhere near an engineer and please take your own precautions etc. I haven’t got zapped yet doing these bends, but I have got minor shocks in other projects.

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Thanks for the tips here, all the bits are in the post so hopefully can have a fiddle with it all over Christmas/NY!
I’ll update with any success/failures! :slight_smile:

@amfas Happy New Year!

I think i’m nearly there! I managed to get all the parts and separated the PCB from the casing. I was ready to start fiddling around earlier when I noticed that all the chips bar one have no writing on them/indication of their part number. Excuse me if obvious, but does that mean that they’re all the same as the one with writing on?
[I’ve linked two images of the PCB for clarity](IMG-1425 — ImgBB IMG-1424 — ImgBB)
Also i’m pretty sure that the Toshiba chip is what i’m after to mess around with, but there are two others that look like they might be usable/chips, right by the Toshiba (first ones starts with ‘MC33’ and the other with ‘TDA’) in the zoomed image

Oh, haha. That’s interesting. I doubt they’ll be the same… or at least, the lack of marking doesn’t mean they are the same as the one with writing. They all appear to be marked with IC numbers, so if you can find a schematic or service sheet it will tell you what they do.

With that said, the PCB also does show the signal path and sections quite nicely, which is useful. I personally would just go for any of those chips and avoid the outside pins. Don’t let an inability to identify a chip stop you from experimenting. That’s half the fun :slight_smile: Be aware that I do say this as somebody who is a bit more cavalier than others may be…

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