The Case Of The Vintage Computer, The Blown Fuse, And The Diode

July 20, 2019 by Jenny List 7 Comments

If you are the operator of a vintage computer, probably the only one of its type remaining in service, probably the worst thing you can hear is a loud pop followed by your machine abruptly powering down. That’s what happened to the Elliott 803B in the UK’s National Museum Of Computing, and its maintainer [Peter Onion] has written an account of his getting it back online.

The Elliott is a large machine from the early 1960s, and because mains supplies in those days could be unreliable it has a rudimentary UPS to keep it going during a brownout. A hefty Ni-Cd battery is permanently hooked up to a charger that also serves as the power supply for the machine, ensuring that it can continue to operate for a short while as the voltage drops. A spate of fuses had blown in this power supply, so we’re taken through the process of fault-finding. Eventually the failure is found in a rectifier diode, the closest modern equivalent is substituted, and after testing the machine comes back to life.

We’re used to reading these stories from the other side of the Atlantic, so we welcome TNMOC saying that this is the first of a series of technical posts on their work. We visited the museum back in 2016, and also featured its famous recreated Colossus.

A Microwave Kiln, From Scratch

July 20, 2019 by Jenny List 15 Comments

We are normally told that microwave ovens are strictly for food only, and that anything else will cause all sorts of bad things to come our way. There can be few readers who haven’t at some time seen the shower of sparks when an inadvertent metallic object finds its way onto the turntable.

A particularly useful non-food application for a microwave oven comes in the form of the small kilns sold for glass fusing. These are ceramic cylinders coated internally with silicon carbide, and [ShakeTheFuture] shows us how to make your own.

Key to the process is ceramic fibre insulation, which is bonded both to itself and to the fused silicon carbide grit by a cured solution of waterglass, sodium silicate. The result can easily reach the required temperature for fusing glass, but also has an application in burning out surplus wax or PLA from a plaster mould. It’s particularly interesting to see the technique with the waterglass in action, and you can see a run-down of the whole thing in the video below the break.

Continue reading “A Microwave Kiln, From Scratch” →

Blacksmithing For The Uninitiated: Curves And Rings

July 18, 2019 by Jenny List 9 Comments

You know the funny looking side of the anvil? That’s where the best curves come from. It’s called the anvil horn and is the blacksmith’s friend when bending steel and shaping it into curves.

The principle of bending a piece of steel stock is very easy to understand. Heat it up to temperature, and hammer it over a curved profile to the intended shape. A gentler touch is required than when you are shaping metal. That’s because the intent is to bend the metal rather than deform. Let’s take a look!

Continue reading “Blacksmithing For The Uninitiated: Curves And Rings” →

BornHack Tease Us With Their Badge

July 17, 2019 by Jenny List No comments

Every August for the past four years, there has been a summer hacker camp on the Danish island of Bornholm, that may be a relatively new kid on the block but is slowly evolving into one of the summer’s essential stop-offs. This year for the first time they are moving to a larger site in an easier-to-reach part of the country, and in the usual build-up to the event they have released a teaser image of their badge.

Of course, you will want to know a little more about it than the picture can convey, so the BornHack folks were kind enough to give us a few more details. At its heart is a Silicon Labs Happy Gecko EFM32HG322F64G microcontroller, the same 25 MHz ultra-low-power ARM Cortex M0+ part that has featured in the previous BornHack offerings. Power comes from a pair of AA cells, and it sports a 240 x 240 pixel colour IPS display and an SD card holder. Connectivity is via USB and an infra-red interface for badge-to-badge communication, and human interface is via a mini joystick switch. Finally, it has a six-way v1.69bis Shitty Addon connector.

By some standards this is a relatively modest offering, but by using an evolution of their hardware from previous years as well as the same proven Geckoboot bootloader they are far more likely to deliver a satisfactory user experience than had they opted for a more ambitious design. We’ll be attending the camp, so we’ll report on the finished article once we have it.

BornHack will run from the 8th to the 15th of August, on the Danish island of Funen. There are a range of tickets still available, from single day visits to the whole week for 1200 DKK (about €160, or $181). Compared to some other events on our community’s calendar, we think that represents a bargain.

A Baby’s First Year In Data, As A Blanket

July 16, 2019 by Jenny List 5 Comments

New parents will tell you that a baby takes a few months to acquire something close to a day/night sleep pattern, and during that time Mom and Dad also find their sleep becomes a a rarely-snatched luxury. [Seung Lee] has turned this experience into a unique data visualisation, by taking the sleep pattern data of his son’s first year of life and knitting it into a blanket.

The data was recorded using the Baby Connect app, from which it was exported and converted to JSON. This was in turn fed to some HTML/Javascript which generated a knitting pattern in a handy format that could be displayed on any mobile or portable device for knitting on the go. The blanket was then knitted by hand as a series of panels that were later joined into one, providing relief as the rows lined up.

The finished product shows very well the progression as the youngster adapts to a regular sleep pattern, and even shows a shift to the right at the very bottom as a result of a trip across time zones to see relatives. It’s both a good visualisation and a unique keepsake that the baby will treasure one day as an adult. (Snarky Ed Note: Or bring along to the therapist as evidence.)

This blanket was hand-knitted, but it’s not the first knitted project we’ve seen. How about a map of the Universe created on a hacked knitting machine?

Review: Shi Yi Tool Sy365-8 Desoldering Iron, Second Cheapest You Can Find

July 15, 2019 by Jenny List 21 Comments

Is the second cheapest tool you can find any better than the cheapest one?

Readers with long memories will recall there was a time when I amused myself by tacking inexpensive tools or electronic devices to my various orders from the Chinese electronic Aladdin’s Cave. Often these inexpensive purchases proved to be as disastrous or ineffective as you might expect, but sometimes they show unexpected promise, true diamonds in the rough. It’s been a while and life has intervened over the last year, but it’s time to resume this harmless diversion.

Memories Of An Explosive Conclusion

A particularly memorable review came in April 2018, when I bought a five pound ($6.30) desoldering iron. I described it then as an “unholy lovechild of a cheap solder sucker and an even cheaper soldering iron“, and while that was an accurate portrayal it also showed promise as a useful tool that would fill a niche in my requirements. Desoldering is always slightly annoying, and a heated desolder pump genuinely does make a difference. Unfortunately for me, the cheap desoldering tool was not a product I’d recommend that anyone try for themselves. A combination of questionable electrical safety and a propensity to explosively deconstruct itself meant it has languished unused in my big box of cheap junk, and I’m still without a decent desoldering solution. It is time to buy something better, and in the rich tradition of reviewing inexpensive stuff I decided to pick up the next cheapest desoldering iron I could find. Eight pounds ($10) secured me a Shi Yi Tool Sy365-8, and I set to on this review. Continue reading “Review: Shi Yi Tool Sy365-8 Desoldering Iron, Second Cheapest You Can Find” →

Alan Turing To Be The Face Of Fifty Quid

July 15, 2019 by Jenny List 24 Comments

The Bank of England has announced that the new face of the £50 note is to be Alan Turing. This news follows a round of public nominations for a scientist to fill the space, and Turing was in the running with some stiff competition from the likes of Stephen Hawking and Ada, Countess Lovelace.

The fifty is not a note you’ll see very often even if you’re a Brit, it’s the one you’ll usually only come into contact with if you’ve bought a second-hand car, but the importance of this move goes beyond whether or not the note will be proffered at the bar for a foaming pint of mild ale. It’s not an honour that is handed out lightly, and it is particularly poignant in the case of Turing who despite his wartime codebreaking and genesis of the discipline of computer science was disgraced and pushed to suicide in the 1950s when he was discovered to be gay.

Will Hardware Pictured on the Bill Be as Famous as Turing Himself?

The bank has not yet set the engravers to work, but they have generated this mock-up that features alongside Turing himself a table from a Turing machine example superimposed on a picture of an early computer rack. We don’t think it’s EDSAC or Manchester Baby, it’s not a Bombe and it definitely shouldn’t be Colossus as he had little to do with it, but we are sure that among our readers will be someone who can provide a positive identification. We hope that whatever the final design may be, it does justice to Turing’s legacy.

Continue reading “Alan Turing To Be The Face Of Fifty Quid” →