HDMI For The Color Computer 2

September 2, 2026 by Zoe Skyforest 8 Comments

[Scott Baker] bought a TRS-80 Color Computer off eBay some five years ago. He’d always intended to add a CoCoVGA or CoCoDV upgrade to hook it up to a monitor, but the device was sold out and his name never made it off the waitlist. Thus, he decided to build his own solution to give the classic machine a proper HDMI output.

The concept behind the project is simple enough—grab the digital signals that feed the MC6847 IC responsible for generating the analog video output, and use them to create an all-digital video output over HDMI. [Scott] achieved this by using a Tang Nano board, which hosts a Gowin GW1N-1 FPGA. It’s able to snoop the signals heading to the MC6847 and, with some supporting components and level shifters, it can spit out video befitting modern screens. To make the system nicely complete, an analog-to-digital converter is also included to pick up the analog sound output from the TRS-80 and spit it out down the same HDMI cable. Such convenience!

There’s something strangely anachronistic about grabbing a TRS-80 off the shelf and hooking it up to a flatscreen with a single HDMI cable. Regardless, it’s a pretty great way to play with your old machine without having to futz with heavy old CRTs. We’ve featured plenty of similar projects before, too. Continue reading “HDMI For The Color Computer 2” →

Get Your Monitor Transmitting VHF With A Browser Tool

August 30, 2026 by Zoe Skyforest 30 Comments

If you’re intending to transmit on the VHF band, you’re probably going to reach for a handheld or some kind of rackmount rig in your ham shack. But you needn’t bother with all that complexity, when you can use the computer on your desk to spit out such signals using a simple browser tool from [Efe].

The concept is straightforward—[Efe]’s tool manipulates pixel clocks in order to create spurious transmissions from your computer’s graphics hardware. The math pencils out pretty easily—multiply the horizontal resolution by the vertical resolution by the refresh rate, while paying attention to the precise timing of the video standard your monitor is using, and you’ve got your transmission frequency. For example, for a screen displaying 1080p at 60 Hz, with the CEA-861 timing standard, your horizontal and vertical resolutions are 2200 and 1125 respectively when paying attention to the requisite blanking intervals. Multiply those by 60 hz, and you’ll find you’re creating a signal at 148.500 MHz. Leverage this by displaying the right pattern of black and white pixels to maximise changes in voltage state on the HDMI or DisplayPort lines, and you might create a strong enough signal that you can actually pick something up. [Efe] created a tool to display these patterns to send simple Morse code messages over VHF just by flickering your screen just right.

You can test the transmitter tool for yourself here, right in your browser. You’ll want to hold your radio’s antenna nice and close to the monitor to see if you can pick up much of a signal. After all, the monitor, connectors, and cable are all built to optimize for clear signal transmission to the display, while preventing signal from leaking out to interfere with surrounding equipment.

Of course, a fair warning—you’re not supposed to intentionally transmit on bands you’re not licensed for, even if it’s incredibly weak and unlikely for anyone else to notice in a scenario like this. Still, it’s an interesting project that shows you just how electromagnetic interference can leak out of just about anything under the right conditions.

A Capable KVM Built With The ESP32

July 30, 2026 by Zoe Skyforest 17 Comments

[Evgenij Spitsyn] spotted a KVM build on these very pages some time ago. That inspired their own build, leveraging the versatility of the ESP32-P4 microcontroller.

The concept is straightforward. Named the ESPKVM, the device is designed to hook up to a computer’s HDMI and USB ports. It captures the video output, while presenting itself as a standard keyboard and mouse device. In this way, it allows remote control of the machine over IP. It achieves this feat with the aid of the Toshiba TC358743 HDMI-to-CSI bridge, which is essentially the video capture hardware of the build.

The video output of the machine is streamed in MJPEG or H.264 format. The device is capable of serving up storage from a micro SD card or the onboard flash, as well as handling things like power/reset control and wake-on-LAN. All in all, it’s a very complete package, and full of useful features. Just don’t use it over the public internet yet — [Evgenij] notes it hasn’t been reviewed for potential security holes yet, even though it has some basic authentication features baked in.

If you’ve got an ESP32-P4 ready to go with a TC358743 HDMI bridge, you can actually head over to the ESPKVM website and flash the code right in your browser to get going. Meanwhile, if you found this build interesting, you might like to scope out the one that inspired it. If you’re cooking up similar utility hacks, be sure to notify the Hackaday tipsline.

Original PlayStation Brought Up To Date

April 14, 2026 by Dave Rowntree 20 Comments

In a satisfying blend of classic console restoration and modern modding, [Elliot] from the Retro Future channel has transformed a broken, dirty PlayStation into what they call the “ultimate PS1.”

The first step was to deal with the really grungy case. The shell was soaked in dish soap and given a good brushing before being packed and sent to a collaborator. Upon inspection of the internals, several unknown modifications to the PCB were evident. These were likely to support playing home-burned copies of pirated games, as well as an NTSC region hack (for this PAL version of the console), courtesy of a dodgy-looking crystal oscillator hanging on the end of some wires.

Luckily, the PS1 product design is highly modular, giving excellent repairability, which made reversing this a doddle. The mod wiring was removed by simply desoldering it, but the cut traces needed to be cleaned up and reconnected to return it to stock condition.

Continue reading “Original PlayStation Brought Up To Date” →

Prevent Your Denon Receiver Turning On From Rogue Nvidia Shield CEC Requests

March 5, 2026 by Maya Posch 15 Comments

In theory HDMI’s CEC feature is great, as it gives HDMI devices the ability to do useful things such as turning on multiple HDMI devices with a single remote control. Of course, such a feature will inevitably feature bugs. A case in point is the Nvidia Shield which has often been reported to turn on other HDMI devices that should stay off. After getting ticked off by such issues one time too many, [Matt] decided to implement a network firewall project to prevent his receiver from getting messed with by the Shield.

The project is a Python-based network service that listens for the responsible rogue HDMI-CEC Zone 2 requests and talks with a Denon/Marantz receiver to prevent it from turning on unnecessarily. Of course, when you want these Zone 2 requests to do their thing you need to disable the script.

That said, HDMI-CEC is such a PITA that people keep running into issues like these over and over again, to the point where people are simply disabling the feature altogether. That said, Nvidia did recently release a Shield update that’s claimed to fix CEC issues, so maybe this is one CEC bug down already.

Vintage Film Editor Becomes HDMI Monitor

February 11, 2026 by Jenny List 12 Comments

With the convenience of digital cameras and editing software, shooting video today is so easy. But fifty years ago it wasn’t electronics that stored the picture but film, and for many that meant Super 8. Editing Super 8 involved a razor blade and glue, and an editing station, like a small projector and screen, was an essential accessory. Today these are a relatively useless curio, so [Endpoint101] picked one up for not a lot and converted it into an HDMI monitor.

Inside these devices there’s a film transport mechanism and a projection path usually folded with a couple of mirrors. In this case the glass screen and much of the internals have been removed, and an appropriate LCD screen fitted. It’s USB powered, and incorporates a plug-in USB power supply mounted in a UK trailing socket for which there’s plenty of space.

There’s always some discussion whenever a vintage device like this is torn apart as to whether that’s appropriate. These film editors really are ten a penny though, so even those of us who are 8 mm enthusiasts can see beyond this one. The result is a pleasingly retro monitor, which if we’re honest we could find space for ourselves. The full video is below the break. Meanwhile it’s not the first conversion we’ve seen, here’s another Hanimex packing a Raspberry Pi.

Continue reading “Vintage Film Editor Becomes HDMI Monitor” →

Converting A 1980s Broadcast Camera To HDMI

December 1, 2025 by Bryan Cockfield 14 Comments

Although it might seem like there was a sudden step change from analog to digital sometime in the late 1900s, it was actually a slow, gradual change from things like record players to iPods or from magnetic tape to hard disk drives. Some of these changes happened slowly within the same piece of hardware, too. Take the Sony DXC-3000A, a broadcast camera from the 1980s. Although it outputs an analog signal, this actually has a discrete pixel CCD sensor capturing video. [Colby] decided to finish the digitization of this camera and converted it to output HDMI instead of the analog signal it was built for.

The analog signals it outputs are those that many of us are familiar with, though: composite video. This was an analog standard that only recently vanished from consumer electronics, and has a bit of a bad reputation that [Colby] thinks is mostly undeserved. But since so many semi-modern things had analog video outputs like these, inspiration was taken from a Wii mod chip that converts these consoles to HDMI. Unfortunately his first trials with one of these had confused colors, but it led him to a related chip which more easily outputted the correct colors. With a new PCB in hand with this chip, a Feather RP2040, and an HDMI port the camera is readily outputting digital video that any modern hardware can receive.

Besides being an interesting build, the project highlights a few other things. First of all, this Sony camera has a complete set of schematics, a manual meant for the end user, and almost complete user serviceability built in by design. In our modern world of planned obsolescence, religious devotion to proprietary software and hardware, and general user-unfriendliness this 1980s design is a breath of fresh air, and perhaps one of the reasons that so many people are converting old analog cameras to digital instead of buying modern equipment.