Ali Naci Erdem

For a long time, I had a dream. A network attached storage (NAS) solution to keep my backups on. I’m a little mad when it comes to backing up. Do not feel all right without at least 3 copies of the same thing on different places. When I was working on a 3d game engine project many years ago (was using DirectX8 using visual basic to be specific), I have lost 4 months of work to an MS DOS 6.22 installation disk that I carelessly used to recover my Windows 98 installation. It didn’t play well with my HDD that is larger than 2GB.

I was once into hobby RC airplane stuff – unfortunately don’t have the time to fly these days. (Check my first flight here ) Got myself a cheap 6 channel FM transmitter on eBay back in the day, not that 2.4 GHz rubbish, one with a huge antenna, you know. It was a much cheaper option then. Not of very high quality, but capable of doing many cool stuff and it is highly configurable. It is possible to change throttle curves, do mixing etc. Configuration process involves connecting it via an “apparently” serial connector to its USB dongle (which is then a serial to USB converter) and a computer. Install an old school t6config program (still not an idea where I get it) on a Windows PC and you’re good to go. The serial connection is also used for controlling RC simulations although with a lot of effort. You need to intercept serial stick commands with a software tool (I remember using ppjoy) and map them to real joystick inputs, which the TX is not very helpful a...

I am collecting vinyl for the last 10 years although I have a rather limited collection of about a 100. I really enjoy listening music on vinyl when I have the time. Large cover art, handling the physical medium, clarity and separation of different instruments and vocals, occasional posters and stickers have always been attractive to me. On the other hand, it is a demanding and expensive hobby even though the recent comeback brought the prices down a little. It is never as simple as clicking “next” on your Spotify or Apple Music playlist in the middle of a song. Every time you bring out a record from its sleeve, you need to carefully remove it and place on the platter and clean it with an anti-static brush to minimize surface noise and prevent damage to the grooves. The stylus is literally running on these grooves and vibrate to generate sound. I highly suggest you watching Applied Science’s video for a great visualization of the process BTW. Being so mechanical and r...

Previously I have started writing on fixing my korg i5m ( part-1 ). Removing the ROM chips was not fixing the problem but taking advantage of this opportunity, I have started trying to dump them out. The problem was that I was not sure if I am reading correct values or not. After working for hours and fiddling with address lines using an oscilloscope, I was able to get some consistent results. Sometimes some of the address lines was getting stuck resulting in repeating patterns in the dump. To make things worse, the memory layout of samples is not very clear except for GM1, which apparently just have 8 bit signed PCM data all aligned properly. After getting an acceptable output for this particular chip, I am pretty confident now that I am doing things right but have some connection issues due to contact resistance (or maybe CMOS-TTL incompatibility as someone over hackaday has suggested). Reading the contents of every chip and being able to sometimes get the same exact data out increa...

Recently I was working on fixing a korg i5m 1995 workstation -that I’ve bought as is on eBay years ago- which has a noise problem in the output. A mechanical but not random weird noise. I also have an i5s (a version with the keyboard and speakers) and I like the samples of that device, so ordered this module version for repairing. After checking voltages and power supply, I first suspected the DAC on the output stage. Easily found a replacement online, waited for it to arrive from China and replaced, with no luck, same problem. Service and user manuals are available for this model online and troubleshooting steps in the service manual turn out ok except for the checksums. But this was the same in my old working i5s, giving random checksum values each time I run the tests. After fiddling around for a while, I decided to desolder the ROM chips in order to narrow down the problem. The system has a 16 bit main bus connecting ROMs RAM and various IO and three MX23C1610MC-15 PCM mask RO...

Found an old (actually late 70s) TV camera and did my own mod. Removed most of its guts. Removed the lens on the picamera and mounted the camera module on the lens of this monster. Writes videos to an external USB card reader. It is fully programmable so I can make timelapse, stop-motion and stuff. Since the cost of a quality raspberry pi sound card is a little too expensive, I decided not to use this for daily shooting, instead I’ll use an external audio recorder with a clapperboard etc. Runs on a Li-Po battery and can be used as long as 2 hr with 1500 mAh capacity. The old analogue iris mechanism was replaced with a mechanical one which can be seen in the upper part of the lens right integrated on the handle. I’ve used many of the camera’s original switches and interfaces to control the pi over GPIOs. Thinking of replacing the CRT viewfinder with an LCD screen which is on its way from china. Focusing with the onboard CRT is really hard. I’ll update as the new s...