Need help on Circuitbending Vivanco Videomixers, know your tools

Hey guys, im really focused on this projects, im very happy to see videos of cracks who use this old mixers and bent them. As someone whos not into electrics, is hard to find a full detailed guide to get it done.

Im a Videartist, doing Imagefilm, Musicvideos etc., used AfterEffects to simulate all those glitcheffects for more than 10 years now. Only now, i saw the true source of this genre. I always wondered how to get this glitch effects from vhs. With those Videomixers and the connection to a laptop, im deeper then i ever was. I love to ride this wave, but i want to control tohe wave.

I tried. I circuitbend over 5 devices the last week. I had some very good beginnings, done some great effects and packed them in. The thing is, 2 bendings worked out, sometimes 3, but when i go deeper. I always roast something, blackscreen. At 1 device i blackscreened it after my 3 touch on the pcb in search of bendpoints via crocodile clips. Sometimes i can fix them by soldering random points together. I got back my image, but my effects are not the same any more, or do nothing. And no matter which points i bend, there is not close the abundance of the previous bended points. You can have luck, but the randomness, has its end, and im discovering it. So i decided to look deeper, there is a tutorial on youtube from a guy called “cusabir”, he is the most detailed. But also there, for a newbie, some steps just not rcomprehensible, for example, the step where he uses the multimeter (diodmod) to check if there is power on the pins. So im going nextlevel, i take a multimeter, im using the red pen on the middle of the transistor. The black pen goes from point to point (potencial bendpoints), to see what value is on the pins, sometimes there is 1 (1 is nothing i think? sometimes there is 1.625 sometimes there is 625, 322 and so on.

So i taught, i need to go with the ones which have no power (like cusabir says in his video) multimeter stays at 1. But nothing happens there, if i connect them. So i taught, i trie the ones with the value for example 322, 625 and so on. And see there, something happens. But also after some connections, things get out of hand. Blackscreen again.
This other tuber called “allmyfriendsaresynths”, he gives a lot of infos, this guys great and always recite himself that he has no pre-calculations and just goes for it, but when i see what he comes up with, like massive modificated machines. There is no chance, there is a way to do this without specified knowledge of the potencial of the bendpoints.

So i thinkg my mainproblem is, to idetify the right bindpoints, dont get me wrong, i really tried to see so mutch videos about, multimeters, electric, but specificly for this topic of bending, i saw nothing which gives me the right path. Maybe some of you guys, throw some stones to get me on the right path.

At the frontside on the PCB, there are this small chips with numbers on it like 471, 301,182. What are those, is this a refernce to use?

Here the video of the guy cusabir: Video Bending Tutorial | Sima Pro Edit 3 - YouTube
Greetings Caesar

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…so, lets try to call him here: @amfas

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…there are a few fully documented projects out there - problem is: you will need to get that exact hardware to do those bends…

…for starters:

LoFi Future - Circuit Bent By Design
→ [not glitch: The Pixelmusic 3000 Atari Video Music Clone - ctrl.alt.rees]
BPMC DIY Series: Fritz Telegraph Mini | Glitchart.com

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The Lofi Futrure Circuit bend, is quiet nice. Its a interesting journey to study this datasheets. In his case, i really would love to understand, how he was able to identify the power and ground pins through the datasheet, which details are the indicators. For example how much volt significant to markthem as power or ground. Input current, the vdd stuff?

In this case he is connecting the parts on the ram on the frontside on the board, i always did it on the backside, not even considering to do something on the chips.

Hiya @caesar. Thanks for the kind words. I think I saw your comment on one of my videos.

There are some tips/thoughts/tricks below from my experimentation. However, I am not an electronics guru. Take everything I say or do with a massive pinch of salt - particularly around safety.

  • In general you want to avoid the power pins/lines. You can get some interesting results in certain situations, but often you will blow chips or other components if you connect these up.
  • The most ‘sensible’ and comprehensive way to ensure you don’t hit the power connections is to find a schematic of the device.
  • Alternatively, you can remove the PCB, flip it over, and then look up the particular chip spec sheets online to identify what pins are power, and avoid them.
  • I am far too lazy for that, and so I tend to just avoid the top and bottom pins on the chips, as they tend to be where power is. I am not particularly careful about that though.
  • Experiment with the power on (to see the results), but turn off the device and disconnect the psu when soldering. That seems to put less stress on the circuit, and results in less black screens for me.
  • Sometimes black screens can be remedied by restarting the device.
  • Avoid anything that brings mains power into the device itself (as in, with an internal transformer), unless you are confident you know what you are doing.
  • Devices with DC Power - so external transformers are ‘safer’ in that the voltage inside the device is lower. Still, any device connected to mains will be risky to bend, and you want to avoid going anywhere near the power connections/look out for the power lines that come off of them.
  • You can use a resistor on one end of your crocodile clip to help find bend points with less ‘full’ contact.
  • I use a breadboard with different potentiometer values, and connect up clips to different points to see what value gives the greatest amount of control over a bend.
  • Experimenting with capacitors can be fun.
  • I don’t bother with a multimeter.
  • Forget about trying to retain specific effects that you find early on. The more elements you add into a bend, the more difficult it is to preserve or find a particular effect.
  • I enjoy the process of exploration with video-bending, and don’t bother to document the bend points on devices to any real extent outside of some general photographs. If you want repeatable results, you need to have a much more methodical approach in terms of documentation etc.
  • Generally I just poke about with crocodile clips, avoiding the power lines/pins, experiment with different potentiometer values, find particular contact points which are linked to certain portions of the enhancement circuit (e.g. look for points which are already connected to the video enhancer’s ‘contrast’ or ‘colour’ knobs), then try connecting them up to different places. Consider using momentary or latching switches etc.
  • Connecting up points to the input and output pins of the RCA connections themselves can often bring wild results.

I genuinely know fuck all about electronics (I can’t read schematics) and I am terrible at DIY, so if I can manage it, anybody can.

Hope that helps!

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Yes sir, definetly got some comments on your channel!

Thanks for your well spoken tips. I try to get to the point, there are some things i dont understand, so i edited some pictures, to get a missunderstanding out of the way.

ok, so when i look at the chip on the pcb front, and if i shine with a light on the pcb. At the backside i cant see that the chip is connected with points on the back maybe just 1 point on the back is connected via lines to the chip. Here pictures to visualize what i mean:


same here, top and bottom pins of the chips, that means you connecting dots directly on the chips? not only on the backside of the pcb?

Power lines is this?:

Power Pins?

I’ll try answer the questions above, though I am not at home at the mo, so can’t edit pictures to help.

No. I only connect points on the bottom of the PCB. What I mean by top and bottom pins are that I avoid connecting the top and bottom row of pins on the chip (generally). So if you have a chip that looks like this:

1 x x
2 x x
3 x x
4 x x
5 x x

Then I avoid connecting anything to the pins on rows 1 and 5.

I can’t tell from those pictures whether or not they would be the power lines. Usually you can identify them as coming out from the transformer - where the power supply connects.

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Ok got you man, that gives me much more clarity! So if i get it right, thats on the pictures for example the 3 pins, you call a chip: ( i marked a red x, what i understand not to connect to)

20221103_201219xxxxx
20221103_201219xcx
20221103_201219xx

It seems like you are maybe confused about what a chip is. A chip in this case is an integrated circuit. It’s one of the black rectangles with two rows of pins on each side. These control a lot of the functions that are interesting to bend. Not all contact points in a row will be connected to ic chips. It might be worth looking up some basic guides on electronic components first if you haven’t already, so you can identify the IC chips and have a better idea of what the above all means.

Jeer i was wondering, i thaught this are chips, but as i mentioned in the earlyer post, i could not see a direct connection between the chip and the points on the backside of the pcb. I definetly see the two rows of pins, like a centipede, but this pins not showing on the backside of the pcb (where im bending).
But now, i get closer to understand the connection. On this pictures, this red circled points, are more likely what you talking about? Man, thanks for your patient passion!

i mentioned this picture earlyer:

( i could not see connecting dots from the chip on the backside, but now i start to understand that the points marked, connected to the chip)

From this part of your message I understand that your main preoccupation is to achieve and realize video glitches and effects in a genuine, completely realistic way, while having control over them.
I may be wrong but I don’t see much enthusiasm about soldering in your words (personally, I don’t have any myself!). Do you actually find the circuit bending part interesting in itself, or is it just a mean that seems required to reach your end?

In other words, are you sure you need / want to circuitbend anything in the first place? To achieve all sorts of glitches and effects you do not need circuitbent devices, not necessarily. Many glitch machines at various prices exist that allow for different effects, and they likely provide better / more reliable control than a DIY project, especially if one is not expert. You can find such hardware listed here: List of Artists Who Make & Sell Analog Video Hardware

Sorry if this was already obvious to you and I misunderstood your request, but just in case…as you wrote, there’s no guide about how to do these things.

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hey, nope man, i started soldering because of the videoglitch stuff. I have to say, im proud, to know how to use this tool, now :). Dont get me wrong, im into it and i wont stop. Im just hungry for more info. But i get to know more info, mostly by myself now. For example, to scan the front plate first, to see where are those little batterylike bastards, i avoid them. But if i already shocked the PCB, and i have to overbridge points to get back the image, this batterybastards could be useful for special effects. Here i got some of my glitch stuff.I really try to go high-tech with the boards, when i have my next job where i can use them, i will deliver.
Im focused on flowing effects, which i can use for video, not just for stills.
Sadly i do not really track the glitch variations.
Here are some random references i took:



This Blue Red Glitch is Massive, its a terminator-CRT screen lookalike:


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thanks for your reply @caesar, good luck and welcome to scanlines!

(but please, do not assume someone is a dude. thanks)

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Back to give some feedback, actually its so easy, when you have the right hardware. I got a videomaster now, you just have to connect the different chips and you good. You have great effects, i have 2 push buttons nad 4 potentiometers on it now. Clean look! On the other hand, in my beginnings i just worked with vivanco videomixers, the bigger ones, the chips are not like the one in the videonics or videomaster, its much less obvious, the big chips are not really affecting much, there are other points you have to connect. In comparison to the videomaster,the vivanco are much more pain in the ass.

Honestly, i found some datasheet for the chips on the videomaster, but im not able to tell, which values i have to look out for, to know on which one is the power.

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Unbenannt
Unbenanndt

For Protocol, when i use this for example, is this info enough, to know what not to connect?
With my knowledge, i would not connect any of those pins to 1,16,8,7 = ?