

Advent of Computing
Sean Haas
Welcome to Advent of Computing, the show that talks about the shocking, intriguing, and all too often relevant history of computing. A lot of little things we take for granted today have rich stories behind their creation, in each episode we will learn how older tech has lead to our modern world.
Episodes
Mentioned books

Mar 30, 2025 • 1h 21min
Episode 154 - ACTing Up
The LGP-30 is one of my favorite computers. It's small, scrappy, strange, and wonderous. Among its many wonders are two obscure languages: ACT-I and ACT-III. In this episode we are exploring the ACTS, how the LGP-30 was programmed in practice, and why I've been losing sleep for the last few weeks.

Mar 17, 2025 • 55min
Episode 153 - The Keypact Mystery
When I was down at VCF SoCal I ran into a strange machine: the Keypact Micro-VIP. It's a terminal without a keyboard, covered in dials, with a speaker and a switch labeled "voice". This chance encounter with the unknown sent me down a wild path. It involved the creeping spread of computing, chicken feed, door to door life insurance salesmen, and at least one early hacker.

Mar 2, 2025 • 1h
Episode 152 - LIVE at VCF - Reviving Retro Panel
A special treat from VCF SoCal. While visiting I had the chance to host a panel on restoration and preservation. I was joined by: David from Usagi Electric (https://www.youtube.com/@UsagiElectric) Rob from Souther Amis (https://www.southernamis.com/) Jim, Former Executive Director Computer Museum of America (https://computerhalloffame.org/home/about/)

Feb 3, 2025 • 1h 1min
Episode 151 - The Friden Flexowriter
Have you ever looked at an old computer and seen a weird typewriter thing tacked on? In most cases that's a device called a Flexowriter. It's half electric typewriter, half teleprinter, half tape reader, and all business! This episode we are chronicling the rise, fall, and weird business dealings of the Flexowriter.

Jan 20, 2025 • 1h 5min
Episode 150 - Starting Windows Up
In the modern day Windows is a power house, but that wasn't always the case. In this episode we are looking at the fraught development of Windows 1.0. During development it was called vaporware, it was panned in the press, roasted at at least one trade show, and even called... "eclectic". Through it all a vision in lime green would take form.

Jan 5, 2025 • 59min
Episode 149 - IDRIS Is Not UNIX
This episode we are taking a trip back to UNIX world. We're looking at IDRIS, the first clone of UNIX. It was supposed to be highly compatible, but use no code from Bell Labs. IDRIS ran on everything from the Intel 8080 up to the IBM System/370. There was even a version that could run MS-DOS programs. Sound too good to be true? Well, that may be the case. Selected Sources: https://archive.org/details/aquartercenturyofunixpeterh.salus_201910/page/n196/mode/1up - A Quarter Century of UNIX https://github.com/hansake/Whitesmiths-Idris-OS - Co-Idris disk images and executables

Dec 22, 2024 • 1h 3min
Episode 148 - Is BLISS Ignorance?
In 1970 a little language called BLISS emerged from Carnegie Mellon University. It was a systems language, meant for operating systems and compilers. It was designed, in part, as a response to Dijkstra's famous Go To Considered Harmful paper. It had no data types. It used the most bizzare form of the pointer I've ever seen. And it was a direct competitor to C. Sound interesting, yet? Selected Sources: https://bitsavers.computerhistory.org/pdf/dec/decus/pdp10/DECUS-10-118-PartII_BlissReadings_Dec71.pdf - Readings on BLISS https://www.cs.tufts.edu/~nr/cs257/archive/ronald-brender/bliss.pdf - A History of BLISS

Dec 9, 2024 • 55min
Episode 147 - Molecular Electronic Computer
In 1961 Texas Instruments unveiled the Molecular Electronic Computer, aka: Mol-E-Com. It was a machine that fit in the palm of your hand, but had all the power of a much larger computer. This was in an age of hefty machines, which made the achievement all the more marvelous. How was this even possible? It was all thanks to the wonders of molecular electronics, and a boat load of funding from the US Air Force. Selected Sources: https://web.archive.org/web/20160304071831/http://corphist.computerhistory.org/corphist/documents/doc-496d289787271.pdf - Invention of the Integrated Circuit, Kilby https://archive.org/details/DTIC_AD0411614/page/n15/mode/2up - Investigation of Silicon Functional Blocks, TI https://apps.dtic.mil/sti/tr/pdf/AD0273850.pdf - Silicon Semiconductor Networks, TI

Nov 25, 2024 • 58min
Episode 146 - The Z4
The Z4, completed by Konrad Zuse in 1945, is a computer with a wild story. It was made from scrounged parts, survived years of bombing raids, moved all around Berlin, and eventually took refuge in basements and stables. In this episode we will follow the Z4's early days, and look at how it fits into the larger picture of Zuse's work. Along the way there is looting, rumors, and even... IBM! Selected Sources: The Computer, My Life - Konrad Zuse's autobiography https://web.archive.org/web/20090220012346/http://delivery.acm.org/10.1145/370000/361515/p678-bauer.pdf?key1=361515&key2=3342588511&coll=&dl=acm&CFID=15151515&CFTOKEN=6184618 - Plankalkul, F.L. Bauer and H. Wossner https://ieeexplore.ieee.org/document/9787324 - Architecture of the Z4, Rojas

Nov 11, 2024 • 1h 1min
Episode 145 - Zuse's Mysterious Machines
Dive into the intriguing journey of Konrad Zuse, whose passion for computing led to the creation of groundbreaking machines during WWII. Discover the innovations behind the Z1, Z2, and Z3, and the political landscape surrounding their development. Gain insights into the Z3's design simplicity while exploring the pivotal concept of Turing completeness. The discussion challenges our understanding of what differentiates calculators from true computers, revealing Zuse's lasting legacy in the tech world.