As a kid in 1998, I was given an old IBM PS/2 to play games on. It only had one problem: with no USB (naturally) and no optical drive in it, I could not add more games to the hard drive, since the floppy drive didn’t work properly. However, I was curious to see an orange light come on, instead of the more familiar green, and there was “2.88” written on its eject button. What… [more]
Something I’ve crafted for the new X-ray experiments: a half wave, eight stage Cockroft Walton multiplier (or a Villard cascade, whichever name you like), submerged in oil, providing a theoretical maximum output voltage in excess of 220 kV with a maximum supply voltage of 10 kV AC, with headroom.… [more]
A real-time, fluoroscopic X-ray setup of my previous attempts with the beryllium-window tube. However, radiographed objects are now placed on a slow moving turntable motor, thus creating a spectacular 3D effect, captured on camera.… [more]
That’s right – the very first IBM Personal Computer, the IBM 5150 – a business-oriented machine and a hallmark platform that started it all, shipped along with an integrated cassette port. Too bad it could only be utilized through the cassette BASIC contained in ROM… Or shall we say thankfully? Yes, this interface was abandoned soon after, for obvious reasons.… [more]
This is a follow-up to my previous article about connecting old 8″ drives directly to a PC equipped with a classic floppy disk controller. Since there is a way on how to do it on a hardware level without paid or proprietary equipment, there still needs to be a free and available software solution that enables the OS to interface these drives, as they were not officially supported… [more]
Unless professionally required, a lot of high voltage enthusiasts do not wind their high voltage transformers at home. This task would be nearly impossible to do without proper coil winding, insulation potting and vacuum-sealing machinery. Thus, high voltage transformers from everyday electronic appliances, such as CRT TVs and computer monitors, microwaves, automobile ignition… [more]
Description: An x86-compatible, ARCnet based thin client.
Manufacturer: Alloy Computer Products, Inc.
Made in year(s): mid to late 1980s, my model in 1987
Country of origin: Massachusetts, U.S.
Status: Working, in good condition… [more]
Earlier this year I’ve got a cheap old Amiga 500 for tinkering purposes. Now, I never really had any Commodore paraphernalia around here, and my first PC was a 486 to play games on, but – some of my DOS favorites were actually ported from an Amiga, so I have decided to give this one a try… [more]
Some five years ago, I had a RepRap 3D printer setup running the Marlin firmware on an Arduino Mega 2560 board. With that long gone, I was thinking about some other projects I could try on it: a floppy drive controller, and perhaps a clock, with some neon indicators I have managed to salvage from a 1970s benchtop multimeter of Czechoslovak provenience. Even though I have to admit that it… [more]
Most PCs tend to boot from a primary media storage, be it a hard disk drive, or a solid-state drive, perhaps from a network, or – if all else fails – the USB stick or the boot DVD comes to the rescue… Fun, eh? Boring! Why don’t we try to boot from a record player for a change?… [more]
The BootLPT/86 project was created to allow booting of classic and vintage x86 systems through the parallel interface using a cross-over LapLink null printer cable. Originally inspired by Martin Řehák’s ROMOS project, it is defaultly provided as a ROM image for any PC-compatible systems, and can also serve as a fallback boot option, should all the other boot options fail… [more]
A third version to go with the third anniversary of CMOS De-Animator!… [more]
With a predictable demise of CRT screens that’ve been phased out of production since the late 2000s, the owners of vintage TVs, monitors or other displaying equipment, kept in a condition that’s just too good to be thrown out, will eventually bump into a problem concerning each and every CRT – or any vacuum tube in general – of decreased cathode emission, … [more]
This article describes three different ways on how to cope with the digital-level RGB videosignal, often found in various computing equipment of the 1980s and early 1990s, so that it can be connected to other display equipment, besides vintage monitors… [more]
This is a great little battery powered PLL-tuned LW/MW/SW/FM receiver with support for single-sideband reception. I got it off eBay one year ago, for approx. 49 EUR including shipping. Receives 100-29999 kHz AM with SSB and FM 76-108 MHz, has 255 station presets, a backlit faux-analog display and small power consumption. I did a full review of its features on Priyom.org as a member… [more]
Derrick was a hybrid monolithic 16/32-bit kernel which I wrote in FASM in 2008, to learn myself low-level Intel x86 assembly along the way. Derrick can be executed on a machine equipped with at least an 80386 CPU, runs from a floppy disk and will execute everything in ring 0 to be as fast as possible… [more]
Description: A regenerative MW/LW AM radio receiver.
Manufacturer: various manufacturers
Made in year(s): 1938 to 1944, as far as originals go
Country of origin: Third Reich and its territories
Status: Working… [more]
Description: Soviet army Geiger counter.
Manufacturer: Unknown
Made in year(s): mid 60s-early 80s
Country of origin: U.S.S.R.
Status: Working, last calibration March 1990… [more]
Apart from flyback transformers or MOTs, automotive ignition coils are also used as high voltage sources by many enthusiasts. Especially those classic cylinder-shaped ones, used in carbureted engines pre-1990, since these were driven directly from the battery (through contact breakers)… [more]
Description: Czechoslovak cumulative γ dosimeter.
Manufacturer: ČSLA
Made in year(s): 80s, my model in 1982
Country of origin: Czechoslovakia
Status: Working, last calibration in 2003… [more]
Vinyl revival, anyone? Yes indeed! Nothing beats the sound of a dust-filled groove, pressed into a biscuit of PVC, mastered from ones and zeros and released today. Plastic disks not your cuppa? Substitute them for wax cylinders! Recorded and played back with a big old horn for that overall analog experience. Oh wait… [more]
This might be the craziest documented experiment/project on my page – a fluoroscopic radiograph of my hand, utilizing my beryllium-windowed vacuum tube setup. For the sake of your own safety and the safety of others, do not attempt to recreate without proper knowledge and protection, as hazards include radiation sickness, increased risk of cancer… [more]
Back in 2008 before starting with high voltage, I have made numerous experiments with flyback transformers and with simple single-transistor drivers, most of these were undocumented. However, this was one of my very first high voltage circuits and my first -electronic- circuits in general, which were marked with some success… [more]
This single transistor flyback driver topology was created in response to achieve higher efficiency and higher output voltages from ordinary CRT television flybacks (diode split flybacks), for experiments such as x-rays or ionic lifters, without having to make any external HV multipliers. Since these flybacks are normally sealed in epoxy and can withstand an output voltage … [more]
The ZVS flyback driver, made popular by Vladimiro Mazzilli, is one of the most efficient and powerful flyback drivers used by high voltage hobbyists from all over the world. The main advantages of this driver are simplicity of the circuit itself, very high efficiency and easily obtainable parts. By tuning it properly you are able to get insane power outputs; beefy flyback transformers… [more]
Now, let me begin this article by stating that this *is not* a so-called “conversion” with an LM317 (or any other linear regulator in general) like you might have seen on thousands of other web pages, nor a so-called “lab” supply that was made just by shorting the PS-ON pin. This is a real ATX to regulated supply conversion, which might come in handy for you.… [more]
Description: Czechoslovak army radiation indicator.
Manufacturer: TESLA or Czechoslovak army
Made in year(s): late 50s-early 60s; 1962 was my model
Country of origin: Czechoslovakia
Status: Not available… [more]
Description: IBM’s failed aim at the home computer market.
Manufacturer: International Business Machines
Made in year(s): 1984-1985
Country of origin: U.S.
Status: Working… [more]
Description: The very first IBM PC that started it all…
Manufacturer: International Business Machines
Made in year(s): 1981 to 1987
Country of origin: U.S.
Status: Working… [more]
Description: Czechoslovak army Geiger counter.
Manufacturer: Rudi Čajavec and TESLA
Made in year(s): late 60s-mid 80s; 1969 is mine model
Country of origin: Yugoslavia & Czechoslovakia
Status: Working, last calibration Feb 2006… [more]
As a follow-up to my previous article about the IBM PCjr and its quirks and features, I have decided to create KeybJr – a small open-source project, that allows the PCjr to use a regular keyboard of the era, through both cable or the infrared link. This is because the system did not contain any provisions of connecting a normal PC keyboard… [more]
Description: A portable full-track tape recorder.
Manufacturer: Kudelski SA
Made in year(s): 1958-1968
Country of origin: Switzerland
Status: Working… [more]
If you have a sweet spot in vacuum tubes, used in vintage electronics, you might have seen a special kind of a tube that was used in many pre-war AM radios as an indicator of signal strength, thus, proper tuning. And with a simple circuit like this one, you can make it bounce to the rhythm of your music!… [more]
In other words, finding a more creative use for the Arduino Mega than a neon clock: to be able to read and write all sorts of old data storage media and send’em over USB, blending old technology with new.
Originally inspired by the ArduinoFDC project, I have decided to try a different approach: instead of using the Arduino to talk to a floppy drive directly, why not leave the hard … [more]
This very simple circuit can be used to verify the proper functionality of each cathodes in a Nixie tube, which was the predecessor of the solid-state LED 7-segment display, back in the 1960s and early 70s. The main anode voltage is obtained from a simple, battery-powered flyback inverter with just enough voltage to strike the glow discharge, and an adjustable resistor current limiter… [more]
The infamous PC junior celebrates 40 years since its day of announcement, and for this “special occasion” I have decided to make a short re-visit to one of the experiments I did 3 years ago: booting from a vinyl record utilizing the cassette tape interface… [more]
Description: Czechoslovak military Geiger counter.
Manufacturer: ČSLA
Made in year(s): early 1960s
Country of origin: Czechoslovakia
Status: Working, last calibration April 2004… [more]
Tried searching the keyword “geiger counter” on Google, or even better, on YouTube? Now, how many of them contained a multitude of transistors, analog microchips or even digital microprocessors, and no shielding at all? Well, whatever the count is, a majority of them – if not all – are going to fail miserably, due to a huge electromagnetic pulse, when the… [more]
Description: A laptop notebook computer.
Manufacturer: Siemens Nixdorf Informationssysteme AG
Made in year(s): 1993-1996, my model in 1996
Country of origin: Germany
Status: Working, in good condition… [more]
To go along with flyback drivers, X-rays and other high voltage stuff, I have decided to build myself a Tesla coil. Because I live in an apartment building though, there would be no place to accommodate and run monstrous coil designs, not mentioning interference, so that is the reason why I’ve opted for small and sweet portable setups like this one is.… [more]
As a teenager, I used to publish small freeware Win32 applications and system tools under the name ST-WARE Softworks. Because the original site is now defunct, I decided to put up a mirror for all of them here. Feel free to share… [more]
Description: A semi-professional 2-track tape recorder.
Manufacturer: Willi Studer GmbH
Made in year(s): 1977-1997
Country of origin: Germany/Switzerland
Status: Working, in good condition… [more]
Description: Single speed, 4-track stereo tape recorder.
Manufacturer: TESLA Pardubice
Made in year(s): 1980-1983
Country of origin: Czechoslovakia
Status: Working, in good condition… [more]
Description: Two speed, 4-track “Hi-Fi” tape recorder.
Manufacturer: TESLA Přelouč
Made in year(s): 1982-1986
Country of origin: Czechoslovakia
Status: Working, in good condition… [more]
Description: Two speed, 4-track mono tape recorder.
Manufacturer: TESLA Pardubice
Made in year(s): 1973-1976
Country of origin: Czechoslovakia
Status: Got rid of it… [more]
Description: A portable black and white TV.
Manufacturer: TESLA Orava, k.p. Nižná
Made in year(s): 1982-1989
Country of origin: Czechoslovakia
Status: Replaced it with a Merkur II… [more]
Description: Two speed record player with radio.
Manufacturer: TESLA Bratislava, k.p.
Made in year(s): 1983-1985
Country of origin: Czechoslovakia
Status: Working… [more]
Description: An 8080-based 8-bit computer.
Manufacturer: TESLA Piešťany (later TESLA Bratislava)
Made in year(s): 1983-1989
Country of origin: Czechoslovakia
Status: Working… [more]
Description: Composite monochrome monitor.
Manufacturer: TESLA Orava, k.p. Nižná
Made in year(s): mid- to late 80s
Country of origin: Czechoslovakia
Status: Working… [more]
Triple333, or 333-333-333, is a Wolfenstein 3D-like first person shooter I’ve made, heavily inspired by -among others- the Wyoming Incident, a fake television hijack, the Max Headroom WTTW TV pirate, who was for real, Russian “Wyoming incident parody” БЕЗНОГNМ and the scary ВИD mask, which itself was a logo of a Russian private TV company.… [more]
Now here’s a novelty, besides high voltage! A two watt 445nm “M140” diode in heatsinked, focusable housing, all with a regulated constant current driver. So, here’s the result of jumping on the bandwagon of lasers… [more]
I have once stumbled upon an interesting article from 2018 published on retrocmp.de, discussing about provisions on connecting an 8″ floppy disk drive to a PC. You know, those huge “boat anchors” that accept flexible disks just four inches shy of an LP record, in exchange of a couple of hundred kilobytes data storage. That sort of type.… [more]
The WKSW (Windows / Workstation Kill Switch) is a small, “anti-boss” system-wide utility, which allows you to set up a global hot-key to power down your Windows machine within seconds, making it handy in such situations, where locating the power button or a classic shutdown would cause more trouble… [more]
In 2010, me having already exploited the DY86, a Czech experimenter nicknamed “DANYK” came up with an oddball Soviet vacuum stabilisator tetrode “6VS-1”, which produced copious amounts of X-rays in hot-cathode mode. He got pretty good radiographs, nevertheless. So, I have got an inspiration and obtained a few:… [more]
While lurking on eBay on a nice spring day of 2012, I have been lucky to obtain a real gem, for a very cheap price indeed: a special micro-focus X-ray tube, with a Be window on the beam port, mostly for spectral analysis or fluoroscopic scanning purposes, for up to 150 kilovolts with forced oil cooling at high powers; made by a now-defunct American EG&G Astrophysics company… [more]
After receiving a donation of two nice X-ray intensifying screens from Mr. Máca, a Czech radiologist (many thanks!) in 2011, it wasn’t long before I got a hand on a real X-ray tube, obtained through barter trade, with some luck, too. Only then were my previous failed X-ray attempts with DY86‘s and 6VS-1‘s marked with success, at least!… [more]
The DY86 (DY87, DY802) vacuum rectifier was used in most European black and white tube television sets. In hot-cathode mode, it was capable of rectifying up to 18 kilovolts at 0.5 mA. In cold-cathode mode, however, it withstands 40 kilovolts DC inverse for a short time, while providing some soft X-ray radiation enough to set classic Geiger counters off.… [more]
Recently I have been drawn before the commission of a local telco bureau, to take part in an amateur radio examination, by a fellow attendee. The motivation? Well, each time I tinkered with a radio, I always skipped scanning of “ham” bands as I never really found debates regarding signal reports, the weather or their next planned doctor’s visits to be of particular… [more]