Articles by CuriousMarc

Another classic Hewlett-Packard instrument saved from the trash bin: the HP 410C VTVM (Vacuum Tube Voltmeter). Stuff that supports the channel: – Amazon links for the tools I use in the lab (supports the channel if you buy from there) https://www.curiousmarc.com/amazon-links – Channel merch on Teespring: https://teespring.com/stores/curiousmarcs-store – Support us …

Just a few beauty shots of my Friden STW-10 calculator. More videos about it here: https://www.youtube.com/playlist?list=PL-_93BVApb5_GbzkFwdKpuyPo8Ty83h8b Stuff that supports the channel: – Amazon links for the tools I use in the lab (supports the channel if you buy from there) https://www.curiousmarc.com/amazon-links – Channel merch on Teespring: https://teespring.com/stores/curiousmarcs-store – Support us …

We marvel at a MITE AN/TGC-14A(V) Teleprinter, a miracle of teletype miniaturization from 1958. Imagine, only 41 lbs! Stuff that supports the channel: – Amazon links for the tools I use in the lab (supports the channel if you buy from there) https://www.curiousmarc.com/amazon-links – Channel merch on Teespring: https://teespring.com/stores/curiousmarcs-store – …

Core Rope Memory, which contained the programs that landed man on the Moon in the 1960s, is insanely complicated. But that won’t stop Mike from making a custom reader for it, so he can recover Apollo Guidance Computer programs lost to history. Mike Stewart’s Core Rope Visualizer: http://apolloguidance.computer/rope/ Apollo Guidance …

Get your 3D printed parts from PCBWay: https://www.pcbway.com/rapid-prototyping/manufacture/ Usagi Electric (Electric Bunny in Japanese) is visiting us. And I have the very floppy drive his Centurion minicomputer is missing. In this episode, we repair the head actuator brake with a professionally printed 3D part, and demonstrate how to realign the …

The HP plugin we just repaired has a magic RF circuit in it: a diode sampler that goes up to 18 GHz. It is well worth playing a little more with it, and understanding how this extraordinary circuit, which is still relevant today, actually works. Previous video about the HP …

We test a pile of new plugins, and fix the king of them all: the HP 5257A 18 GHz Transfer Oscillator. While we are at it, we demo the HP 5264A Preset Unit and the HP 5262A Time Interval Unit. This completes our repair-a-thon! No kidding, we repaired them all, …

In this revenge-of-the-Teletype episode, we reverse engineer our super-modern (1984!) Whisper Writer Telex machine, and turn it into a fully featured Teletype and RTTY tester. Schematics: https://drive.google.com/file/d/1tic2lBHaCRsTtSF1C1Mao24fTiy_fqKu/view?usp=share_link Full KiCAD RTTY Modem Project Link: https://drive.google.com/drive/folders/1lMn9zfEZFg4ynLAoZNlVssesINuhuwFI?usp=share_link ROMs: https://drive.google.com/drive/folders/1GkatmPj-tZgHao2hYvjU-okzFt7mzzlX?usp=share_link Stuff that supports the channel: – Amazon links for the tools I use in …

We repair our 12.4 GHz Nixie frequency counter plugin, the HP 5255A. It takes a double length episode to get it to behave, and you won’t believe what we find at the end. 5245L Repair-a-thon Playlist: https://www.youtube.com/playlist?list=PL-_93BVApb5_MQBUOVLgdKCaUPY1zaPh_ My HP 5255A manual high resolution scan: https://archive.org/details/hp-5255-a-frequency-converter-operating-and-service-manual-05255-9022-may-1967 Further documentation on my website: …

We modify a cute Panasonic TR-252 portable TV to accept video and sound inputs, so we can use it as a retro computer monitor. Stuff that supports the channel: – Amazon links for the tools I use in the lab (supports the channel if you buy from there) https://www.curiousmarc.com/amazon-links – …