Chris Judevine's Electronics Blog

  This is post from my old blog. I’m not sure how useful this is, seeing how the C64 direct to TV is no longer in production, but if you happen to find yourself in possession of one. There are all sorts of fun mods you can do. For those that don't know the C64 DTV is a joystick that connects directly to your TV and emulates a Commodore 64 computer with 30 games burned onto its internal ROM. It was produced for 2 years between 2004 and 2006. Awhile back I acquired one off eBay, with the intention of modifying it. Inside the DTV there are labeled solder points to connect a PS/2 keyboard and IEC lines to connect a Commodore 1541 drive. There is quite a lot of information on the web on how to modify one of these, and I've been wanting to give it a try. My DTV was a version 1 NTSC board. It has an Atmel ASIC at its core emulating the 6510 CPU and the video and audio chips of the C64, it has 128K of Ram and 2MB of ROM. Internally it has connections for an IEC drive, a Keyboa...

This following is re-post of an article from my old blog from 2008: This is an FM radio transmitter I made using an arduino and a NS73M FM Transmitter. I got the idea from an article on hack a day, if you’re interested in building your own you should check out Mike Yancey's page he built the one that made it on hackaday.com and he does a very thorough job of documenting how all the components hook together. I was impressed by the level of finishing he was able to achieve on the housing; it looked like a commercial product. I wanted to see if I could achieve a similar result, it’s amazing what you can do with some simple hand tools. If your patient with the file, you can make perfectly square holes in aluminum.   On my implementation I omitted the de-bouncing circuit that he has connected to his rotary encoder, and I used a two-line display. Since I omitted the de-bouncing circuit, I couldn’t use the original rotary encoder library since that code uses a hardware interrupt a...

 This is re-post of a blog post I did about 15 years back, I don't know if I would use an Attiny microcontroller if I was to do this today. The price of chips with built in USB is now cost comparable, and hardware USB is more reliable. But it's a fun project and if you happen to have a microcontroller compatible with V-USB it's worth a try.   I was digging though some of my old junk and found a box of old Nintendo stuff and I thought that it might be cool to turn one of the controllers into a USB game pad. Now you can buy a USB NES style gamepad, but what's the fun in that. So, I started looking though my box of electronic parts and found a couple of Atmel Attiny 85 micro controllers. Sweet a chance to try out the AVR-USB library . Now you would think you need a clock crystal to sync the micro controller with the USB, but the AVR-USB library has an algorithm to calibrate the internal oscillator to within +/- 1% accuracy. Which is fortunate because if we had to use a cl...

If you’ve ever tried to browse the web in split-screen mode on a small laptop, you know the struggle. Most websites stubbornly cling to their "grid" or desktop layout, leaving you with tiny text and horizontally overflowing content. Force Phone View is a Firefox extension designed to fix exactly that. By tricking websites into thinking you're on a mobile device, it forces them to deliver a clean, column-based mobile layout that fits perfectly into narrow windows. Key Features Mobile Spoofing : Automatically sends an Android User-Agent to ensure the site delivers its mobile-optimized version. Width Constraint : Constrains the page viewport to 720 pixels , a width that reliably triggers column views instead of desktop grids. One-Tap Control : Toggle the effect on and off instantly using a simple button in the Firefox extension popup. Enhanced Readability : Perfect for researchers, students, or anyone multitasking in side...