16 Step Rectangle sequencer

The bent 486 machine has alot of potential with the right software. It can even be turned into a glitch based drum machine/sequencer. The simple Pascal code is as follows, an array of 16 elements is generated and filled with random numbers. With each step a different rectangle is drawn based in the value in the array that corresponds to the step. The result a basic random melody generator. Next step is to create a UI to allow for note editing. Here is a video enjoy.

Bent TI99 and Atari 2600 Notes from Pixel Form

Pixel Form the creator of the Modified TI99 (Pixel Maelstrom) computer contacted me and graciously shared a few hints about his marvelous modified devices just to clarify my initial assumptions about their operation. So far there has only been 2 modified TI99s, both sold on Ebay. First one utilized SK-1 circuitry with datalines patched to TI99’s dual video chips. Ofcourse the right combination of patches would have to exhist given that the user has patched version of an SK-1 or any other keyboard.

His second version utilized a a somewhat different approach. In this case, audio was split into 3 streams with the help of High Pass, Band Pass, and Low Pass filter circuitry. The signals were then further processed by comparators with individual threshhold controls. The result was a binary 3 digit stream of data. Genius! This data stream drove a transistor array electronically switching various pins on the video chips.

Pixel Form is not about to stop experimenting given the amount of success, future plans include Microcontroller inplementation as well as video bending of other platforms including an Atari 2600 Jp.

Kudos and thanks for sharing. Will definatelly keep one eye on eBay and another on his site.


By a popular request here is my take in the Coldheat device. It works! And it doesn’t suck like some people say. A friend for mine got one at RadioShack when they were GIVING THEM OUT! with a $20 purchase. Being just short of the goal, he purchased AA batteries for the Coldheat to push the amount over. At anyrate it is pretty amazing. It appers to work by conducting electricity through the solder thus heating it to the melting point. So the tip never gets hot persay. However you could get burned by the molten solder pretty easy as a result.
Is this useful for circuit bending? Possibly. If you are working with larger wires and don’t need to melt anything other then solder. Smaller tips are also avaliable. Is it worth $49 for the Ver2? probably not. Would I pay $5 for Ver1, maybe. Also consider conducting current through delicate IC pins, this can potentially false trigger a bend or crash the device.
Is it good to have one in your gig bag incase you have to fix your keyboard while playing a show? Definatelly.

2.99 soldering Iron Review

My soldering iron of 4 years bit the dust last nite. It was a 35 watt Radio Shack and it will be missed. The tip became perma fused and simply broke off when I was trying to twist it. However it was its time. Enter the $2.99 Jameco 35 watt soldering iron.
The first impression ofcourse is cheap chinese construction, yet sturdy and small. Perfect for small electronics. The tip is nice and sharp, doesn’t wobble. The cord is about 4 feet. It fit very well into my soldering stand. However did seem kind of small in it. The heating time was very short. Probably 1 minute before it was ready to go. The new iron fumes quickly filled the workstop. After a succesful evening of soldering I have this conclusion.

Its OK, the biggest and possibly a major problem with this stick is that it gets HOT in the area where you typically hold it. Possibly due to it being in the holder and all the heat traveling upwards. Solution, hold further out or come up with some sort of thermal insulation around the holding area. Another easy thing to try would be to angle the iron holder further down so the heat has a chance to escape upwards before it heats up the handle. All in all very happy with the $2.99 stick. I’ll just have to see how many soldering hours I can rack up on this cheapy.

What toy megaphones are really made of

I’ve heard of people turning these into effect boxes and for the longest time I wanted to see what those things had inside. My newest aquisition was promptly undressed and inappropriate pictures were taken. Oh My!!! Somewhere in that blob of cheap chinese goodness must be an A/D converter for the Mic and D/A that runs into a standard 386 amp. The effects must be some sort of a redementary DSP. However the board shows alot more interesting marks. OSC1 and OSC2 pins would suggest that an external oscillator can be connected. It would be interesting to hook this thing up to an oscilloscope and determine what wave alterations are being done to the signal. My current bending project is going well, so possibly Saturday this megaphone will get explored further.

Good Day for the Circuit Bent Auctions

Looking at the Circuit Bent Items on eBay, I came across some good looking stuff. One is a whacked out keyboard with Video synth capabilities and a load of patch points. Right below that is a MIDIfied Major toy with the keypad setup to send MIDI notes out. Internal tone generator works as well, although that is not MIDI. Next up is a 5 Oscillator box/synth. Sounds are pretty neat, I really love the case though, wonder what it was originally. Last but not least is a circuit bent AM/FM radio. Not sure what it really sounds like, but I have a pretty good idea that its just a feedback circuit of some sort.

Attack of the 9090 clones

www.introspectiv.org has some interesting info on building a 9090 clone.

9090 User Guide | pdf
74kb | date : 16/11/02
9090 Parts list | pdf
29kb | date : 5/Jan/04
9090 Wiring guide | pdf
86kb | date : 14/10/02
9090 Board layouts | pdf
237kb | date : 14/10/02
9090 Schematics | pdf
203kb | date : 10/6/02

There is a complete part list plus board layouts and useful links to other clone sites. It does look to be fairly complicated but the interesting part is the schematics for each individual drum sound.

EA-1 probbing deeper

One of the main ICs located on the board turns out to be H8S/2350 microcontroller.
Taken from the website of Renesas Technology.

“The H8S/2350 Group is a group of high-performance microcontrollers with the internal 32-bit H8S/2000 CPU core, and a set of on-chip supporting functions required for system configuration.

The H8S/2000 CPU can execute basic instructions in one state, and is provided with sixteen 16-bit general registers with a 32-bit internal configuration, and a concise and optimized instruction set. The CPU can handle a 16 Mbyte linear address space (architecturally 4 Gbytes). Programs based on the high-level language C can also be run efficiently.
The address space is divided into eight areas. The data bus width and access states can be selected for each of these areas, and various kinds of memory can be connected fast and easily.
On-chip memory consists of large-capacity ROM (H8S/2351 only) and RAM.
On-chip supporting functions include a 16-bit timer pulse unit (TPU), programmable pulse generator (PPG), watchdog timer (WDT), serial communication interface (SCI), A/D converter, D/A converter, and I/O ports.
In addition, an on-chip DMA controller (DMAC) and data transfer controller (DTC) are provided, enabling high-speed data transfer without CPU intervention.
Use of the H8S/2350 Group enables easy implementation of compact, high-performance systems capable of processing large volumes of data.”

C language with a serial interface, now we are talking!
From further reading it seems like this chip is perfect for music applications. However for some interesting bedtime reading refer to the full Chip Document located Here.

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