Is A Pigeon Faster Than The Internet?

September 2, 2023 by Chris Lott 46 Comments

[Jeff Geerling]’s latest project is for the birds — literally. Even though he has a brand new high-speed fiber optic internet connection, online backups of YouTube video projects still take hours. He decided to see if the conclusions from a 2009 in South Africa study still hold true today — that using carrier pigeons to send files can be faster than the internet. [Jeff] sets up an experiment to send 3 TB of data by homing pigeon a distance of one mile to establish a baseline. Next, [Jeff] sends the same 3 TB of data over the internet, and donning the cap of honorary pigeon, simultaneously embarks on a journey by air to his off-site backup service in Nova Scotia, Canada.

Never underestimate the bandwidth of a station wagon full of tapes hurtling down the highway.

[Jeff] points out that you also have to consider the transfer time of your files onto and from the pigeon-suitable memory cards. He jumped through several hoops to minimize that, but it still consumed 2-1/2 hours total. Trying to keep the comparison fair, he also spent a couple days optimizing his internet connection to eek out the best possible speed. Continue reading “Is A Pigeon Faster Than The Internet?” →

Rocket Range Australia, 1950s Style

August 25, 2023 by Chris Lott 11 Comments

The Film and Sound Archive (NFSA) of Australia just released a digitized version of a 1957 film documentary on Australia’s rocket research back in the day ( see video below the break ). The Woomera test range is an isolated place about 500 km northwest of Adelaide ( 2021 population 132 ) and hosts a small village, an airstrip, and launch facilities. In the Salisbury suburb of Adelaide, a former WW2 munitions factory complex was repurposed as a research center for rockets and long range weapons.

The documentary showcases a wide variety of state-of-the-art technologies from the late 1950s. As ancient as those appear today, a lot of the basic concepts haven’t changed — careful choreography of the launch countdown sequence of events, the antenna and radio systems to receive and store rocket telemetry, photographic records of the rocket in flight, and post-flight analyses of everything to fix problems and improve your designs. They tried to do as much as possible at the Salisbury campus, because as the narrator notes, it’s expensive to work at the distant test range, a concept which is still a consideration today. There’s even a glimpse of the residents’ leisure life in the barren village. It was a different time, to say the least. Continue reading “Rocket Range Australia, 1950s Style” →

Making Electricity At The South Pole

August 24, 2023 by Chris Lott 77 Comments

In case you’ve ever wondered how the South Pole research stations are powered, then a recent blog post, South Pole Electrical Infrastructure by anonymous IT engineer [brr] is for you. Among the many issues covered, let’s look at how the electricity is made and, spoiler alert, how the specially formulated AN8 fuel blend is transported to the generators.

The main source of power is a trio of Caterpillar 3512B diesel generator sets, de-rated to 750 kW each due to the high altitude and the special fuel mixture. Unsurprisingly, all the fuel must be imported to Antarctica, a horribly inefficient endeavor. Fuel arrives initially at McMurdo Station harbor by tanker ship. From there, it can be sent to the Amundsen-Scott South Pole Station in one of two ways. The Lockheed LC-130 is a modified C-130 Hercules cargo plane developed in the 1950s specifically to support polar operations. It is the least efficient method, consuming 1.33 kg to transport 1 kg of fuel. Alternatively, fuel can be dragged by tractors via the South Pole Overland Traverse (SPoT), a 1600 km highway over compacted snow and ice. The trek takes about 40 days and only consumes 0.56 kg of fuel for every 1 kg, which is much better than air.

Continue reading “Making Electricity At The South Pole” →

A 6502 Overlay Debugger

August 18, 2023 by Chris Lott 6 Comments

Retired hardware engineer [Plasmode] recently took on the challenge of building a debugger for the 6502 designed to sit atop the microprocessor while seated in a solder less breadboard. The result is the Diagnostic Overlay for W65C02 Breadboard, consisting of 128 kB SRAM and a 1250-gate CPLD. Except being 0.8 in wide, the overlay debugger is otherwise the same size as the 6502’s 40-pin DIP package, so it doesn’t overhang other portions of your circuit.

Being an initial concept prototype, [Plasmode] mounted the chips dead-bug style on perf board — a process he himself found tiring. If he builds additional debuggers, presumably he will consider making a PCB.

The prototype was constructed using point-to-point soldering with 30-ga wire wrap wire. It was all done under the inspection microscope. There are not many connections, but they are rather tedious so I can only do a dozen or so wires per session. It took me 2 days and several hours total to finish the prototype board.

This design is based on the CRC65 Frugal 6502 Single Board Computer, of course omitting the 6502 itself. Instead of a physical ROM memory chip, he implemented a 64-byte boot loader inside the CPLD and a serial port. This lets him to bootstrap the system over the serial port. He plans on expanding this to include other DIP-packaged retro microprocessors in the future. Check out his Hackaday.io project page ( above ). If you want to dig deeper, he posted the schematics here.

Bringing An ADM-3A Back To Life

August 16, 2023 by Chris Lott 21 Comments

[David] at Usagi Electric ended up with an old Lear Siegler ADM-3A terminal in a trade a couple of years ago. But the CRT face was plagued with so-called cataracts, and the condition of the insides was unknown. The video ( below the break ) shows the restoration process, which went quite smoothly. [David] was relieved that the CRT repair in particular was easy, a fact he attributes to the Texas weather —

The temperature was 110 F / 43 C when he set the CRT outside to bake in the sun for a few hours. Afterwards, removing the “integral implosion protection” plastic screen went better than expected. Everything cleaned up nicely and the screen reinstalled. Introduced in 1976, the main electronics board is chock full of TTL chips with nary a microprocessor in sight. Fortunately the board was substantially intact, and a single missing chip was found hidden underneath the board. [David] gets the terminal up and running in short order, and is confronted with an annoyance familiar to gray-haired programmers who grew up in this era. Most terminals had different sets of commands to control features such as cursor control and clearing parts or all of the screen. Programs often assumed a certain type of terminal. Some terminals could be configured to behave in different ways, and some programs offered the user a choice of terminals. Today your terminal emulator probably still has a few choices of which kind of terminal to emulate, VT-100 being the most common. And eventually some operating systems provided a terminal abstraction, like Unix’s termcap for example.

If you were around in the era where terminals like the ADM-3A were scattered everywhere, what was your favorite terminal and/or terminal feature? And today, do you have any favorite terminal emulator to recommend? Let us know in the comments below.

Continue reading “Bringing An ADM-3A Back To Life” →

New Motherboard Improves Old CRT Television

August 16, 2023 by Chris Lott 36 Comments

While browsing AliExpress from his digital basement, [Adrian Black] stumbled upon what seemed like a brand-new mainboard for a CRT television set. He decided to take a gamble and ordered one. It finally arrived, and was indeed a brand new product from 2023.

DIGITAL MAIN BOARD OF TV, Work ath [sic] HONGXUN products with the care and precision of a sculptor in each step, wonderful have no limits

Dubious marketing descriptions like “High Definition Digital Color TV Driver Board” aside, this turned out to be a fairly well-designed analog TV board. [Adrian] pulls a 20-year-old Magnavox ( Philips ) color television set from storage and begins the transplant operation. One interesting observation is the Magnavox board has almost the same layout as the new board, except for the orientation of the sections. The new CRT neck board had a different connector than the Magnavox set, but was designed to accept multiple sized sockets. [Adrian] just removed the new socket and replaced it with one from the old set. The mechanical issues were a bit more complicated, but nothing that a Dremel tool and a bit of hot glue can’t fix. The 220 VAC power supply was eventually modified to accept 110 VAC, which also enabled him to reconnect the degaussing coil.

[Adrian] has collected some relevant documentation in this GitHub repository, including schematics. Why bother with this at all? Well, until now, he didn’t have any way to test / view PAL RF signals in his lab. He was gambling on the new mainboard having a PAL tuner. It does, but as an unadvertised bonus, it supports NTSC and SECAM as well — but still not “HD digital color TV”, as far as we know. If you want a multi-standard TV in your lab, this solution may be worth considering. It appears there is still a market somewhere for new CRT televisions. If you have any background on this, please let us know down below in the comments.

Continue reading “New Motherboard Improves Old CRT Television” →

Home Network Organization Gets Out Of Hand

August 14, 2023 by Chris Lott 59 Comments

[SpookyGhost] has a big home network, and has taken cable management and server organization to the extreme. He has written about individual components before, but this blog post brings it all together and reviews the entire system. The networking gear is installed in a closet and mounted in a 25U tall 19-inch rack. From top to bottom, here is a brief list of the gear:

Keystone patch panels
pfSense Firewall / Router
Two Cisco Ethernet switches
Redundant internet connections
Shelf of numerous servers
RAID-Z2, 12 each 8 TB SCSI, media storage
NAS RAID, 6 ea 4 TB SAS, 2 ea 800 GB SSD
Video Management System, 48 TB storage
UPS and power distribution units

Most of the Ethernet uses 10GBASE-T and Cat6 cabling and connectors, with some interconnects use fiber optical cable and LC connectors. Unsurprisingly, as this setup grew and grew, [spooky] had to pipe in air-conditioning to the closet.

This is a serious installation, but there are plenty of good ideas for folks with less ambitious networking goals and/or requirements. We liked the swappable Keystone jacks in the patch panels, and the cable pass-through panel with a dense curtain of rubber fringe to keep things looking tidy. If you have any ideas to share on network equipment and cable management, let us know in the comments.