* Posts by Nicko

32 posts • joined 19 Apr 2012

Google Project Zero zeroes in on Google project: Security hole spotted in gVisor sandbox fence

Nicko
Facepalm

Can't really blame Google Groups...

...if a lazy group owner/administrator doesn't set up verified membership checking...

I'm a moderator of a reasonably popular group (over 1,000 members, been going 10 years on Google and on Yahoo! before), and we get almost no spam. Probably had one bit in the last 5 years or so.

If you create a phpBB forum and don't moderate new member applications because you're useless, would you blame phpBB for that?

Solid state of fear: Euro boffins bust open SSD, Bitlocker encryption (it's really, really dumb)

Nicko
Flame

Missing something here?

Crucial no longer make the MX100, MX200 or MX300 series stuff.

Yes, there a lot of these in the field, but folk learn. It'd be good to see the MX500 tested...

Das blinkenlights are back thanks to RPi revival of the PDP-11

Nicko

Happy, happy days...

Happy days. We had an 11/34A at school, running RSTS/E (can't remember the version) - my first ever commercial product (written with another EE at the same university) was a BASIC+ Decompiler.- very popular product,=.

I loved RSTS/E, RT-11, RSX-11,... I still have a J11 chip on on "Shelf of Doom", along with my Sinclair Scientific calculator (still works), my British Thornton slide rule and a set of PDP-8 manuals (among much other detritus).

Somewhere in the loft is an AXP-433 workstation running Windows 2000...

(ex. DECUS Europe OpenVMS Chairman, ex-DEC employee in France, UK & Switzerland).

Chilly willies: Swedish nudie nightclub opens in -11°C to disgust of locals

Nicko

Re: Northern winter habits...

@Nicko; 'a face that was best described as "a cake that's been left out in the rain"'

@AC And hair that looked like sweet green icing flowing down?

I wan't referring to MacArthur Park & Richard Harris (1968), it was originally a W. H. Auden quote from 1963 (said to René Bouché, an artist who sketched him):

"My face looks like a wedding-cake left out in the rain"

https://www.brainyquote.com/quotes/w_h_auden_148305 and many other places.

Nicko

Northern winter habits...

Ah. I had some Icelandic colleagues, one, now sadly deceased (*), had a face that was best described as "a cake that's been left out in the rain". He was only 35 and looked like the nastiest Viking you could image - gentle soul, though.

He could drink a bottle of vodka with no visible effect - I once asked him how he could do that and he replied: "there are only two things to do in the winter, and one of them is drink".

He once woke up in a hotel wardrobe - he'd gone in there thinking it was a toilet, had a pee and fallen asleep...

(*) RIP Gunnlaugur - he knew he'd die young - all the males in his family died from cancer - the Icelandic gene pool is/was limited and there are a lot of families with genetic propensity to certain diseases.

NRA gives FCC boss Ajit Pai a gun as reward for killing net neutrality. Yeah, an actual gun

Nicko

Re: This isn't tone deaf - it is purposefully intended to threaten death

In the UK in 1996 we had a school shooting in Dunblane - shortly after, private ownership of handguns was pretty much banned - the public have never been allowed to own fully- or semi-automatic weapons.

After that one, awful, event, there have been no more school shootings.

Just since 2010 in the USA, in schools there have been:- 146 separate events leaving 156 dead and 247 injured.

https://en.wikipedia.org/wiki/List_of_school_shootings_in_the_United_States#2010s

Absolutely tragic.

Sysadmin crashed computer recording data from active space probe

Nicko

Re: Hmmm ...

Not strictly so - originally there was 10base5 which was over a very very chunky yellow coax with type N connectors and terminators.

In my very early days in this industry, we had lots of it - nominally you had to cut it, add connectors etc., then "T" in a new node, but DEC (Digital Equipment Corporation) produced a tap connector. the H4000, that basically drove a spike into the middle of the cable. This made life a lot easier, but wasn't particularly reliable as if it was moved about a bit, sometimes connectivity would be lost and sometimes the cable would short out.

The manual for the H4000 is here http://manx-docs.org/collections/antonio/dec/MDS-1997-10/cd2/VOL002/0341.PDF

The cables, just like any bus, relies on running as a transmission line - if the end is open, any signal reaching the end will reflect back down the cable, thus neatly messing up all the signal following on.

Simply put, the terminators absorb the signal, stopping reflections. That's a gross simplification, but essentially correct. You had to use the correct terminator for the impedance of the cable - 50ohm terminators at each end for 50 ohm cable, 75ohm terminators for 75ohm cable.

Europe waves through Qualcomm's NXP slurp

Nicko

Re: Bad news

True. All the old stuff from Signetics, Philips, Motorola (Freescale) and a host of others is in there...

Thank the Lord I'm not an EE any more...

Cops jam a warrant into Apple to make it cough up Texas mass killer's iPhone, iCloud files

Nicko

Re: Wrong end of the crime?

Size of the magazine is a detail - I'm not sure of the specifics in the USA, but in the UK for each calibre of ammunition, you have two limits - the number you can hold and the number you can buy at any one time.

e.g. Typically, for .22LR rimfire rounds (used for vermin control), that would be 1,200 holding and 1,000 purchase - the holding is larger so you can purchase in bulk as you run out to save money.

So, even in the UK, a person could have a LOT of ammunition. You just have to buy a lot of spare magazines and pre-fill them. You don't need a license for spare magazines.

Note that in the UK we're not allowed fully- or semi-automatic firearms as private individuals, or for that matter, pistols (except "black-powder") or assault weapons etc.

Oh, and we have a proper licensing system with vetting which, generally speaking, is extremely firmly enforced by each regional force.

Brit broke anti-terror law by refusing to cough up passwords to cops

Nicko

Saudi Arabia has a constitution (of sorts): See https://en.wikipedia.org/wiki/Basic_Law_of_Saudi_Arabia

The UK has the laws of Tort, which are basically a historical record of judgments which act as precedent in protecting individual rights.

Several other democratic countries follow suit: New Zealand, Canada & Israel.

Fancy that! Craft which float over everything on a cushion of air

Nicko
Thumb Up

Built one (or two)...

When I were but a lad at school in SE London, a group of us tried to build a two-man hovercraft powered by (ISTR) a Vauxhall Viva engine, It wasn't very good - too heavy, even with the tubular chassis welded by the metalwork/DT teacher, Terry Kent. The chassis was too flexible and even with one schoolboy in it, it wasn't practical.

We subsequently built one or two (can't remember) single-person smaller craft powered by motorcycle engines. Lift fans were laboriously constructed out of beaten sheet aluminium and a huge number of pop-rivets (which meant that they weren't balanced very well) - thrust was from a commercial small prop. These were "OK" and were flown around the playing fields at the back of the DT workshops...

Sometimes wondered what happened to those...

Google tracks what you spend offline to prove its online ads work. And privacy folks are furious

Nicko

Complete and utter rubbish...

Not untraceable at all - in the UK at least, any substantial cash purchase is likely to raise warning flags with the bank when it's deposited as the bank is an FCA regulated authority.

If someone deposits GBP 26K, you can bet that the bank will want to know where it came from, and why - it's a criminal offence for the bank not to do due diligence (KYC) under the Anti Money Laundering regulations as they are FCA regulated - other bodies who may deal in cash are also covered, regulated or not see https://www.gov.uk/guidance/money-laundering-regulations-introduction

Anyway, what a prattish thing to do - giving the rude salesman the commission on a sale he patently didn’t deserve....

On an almost identical note, many years ago I had been working as a contractor abroad and had a nice pile in the bank. I fancied a new BMW M3 (this was before I was married...), so went to the local BMW dealer, L&*, and had a browse - I was wearing jeans & trainers. Long hair. Bit grungy - dunlop green flash ISTR (them was the days).

A salesman ‘executive’, let's call him Dominic, came over and asked what I was doing there as (and I paraphrase here) I didn't seem to be the sort of person who would own a BMW. I was incensed.

I left. At an NFU BBQ a few weeks later, we arrived in my new M3 bought from a dealer in Scotland who had put the car on the overnight train from Edinburgh to London, driven down to our house in the SE and did me a deal. Amazing service.

So, at the BBQ, I met with the owner of the BMW dealership, let's call him Tim. Tim asked about the M3 as he had one (mine was silver, his was red - he also owned two M1s) and where I'd got it from – he knew it wasn’t from L&*…

I told him the story - Dominic "left" a week later.

BA IT systems failure: Uninterruptible Power Supply was interrupted

Nicko

Complete and utter rubbish... and Unforgivable.

"...our source said, the power control software controlling the multiple feeds into the data centre didn’t get the switch between battery and backup generator supply right at the critical moment – or, potentially, if someone panicked and interrupted the automatic switchover sequence – it could have resulted in both the battery supply and the generator supply being briefly connected in series to the power bus feeding the racks. That would result in the data centre’s servers being fed 480v instead of 240v, causing a literal meltdown."

Hogwash.

No. No. NO. Any modern DC has a sequence where the utility feed comes into a box called an ATS (Automatic Transfer Switch). Under normal circumstances, ALL the equipment in the DC is powered from the UPS which is on-line at all times.

The UPS has two roles - maintain the output voltage at a steady 230V to cater for input supply power fluctuations, and to load-balance the input currents across the three supply phases (most modern UPS systems don't care much about output load balancing, though it's good practice to try to balance them to get the most out of the UPS).

On-line UPS systems take the input power feed, convert it to DC to charge the batteries, then they have inverters that take the DC from the battery and convert it into clean AC for the data center. Unless the UPS is in bypass mode for maintenance, this is the case at all times for all modern data center UPS systems.

If the utility feed fails, the ATS detects this and immediately sends a signal to the genset to start the generators.

The UPS should have about 10 minutes of run time with no utility input - this is to cover the start-up of the genset, and if the genset doesn't start, time to send a signal to the servers that they need to do an orderly shutdown (this is done by s/w agents on the servers - signalling normally by IP).

At NO TIME should there be a detectable fluctuation in the power to the data center - all that happens when the input utility supply fails is that the batteries in the UPS are no longer being charged and start to discharge (hence the 10 minute run-time) and the genset starts up..

As soon as the ATS detects that the genset is producing the correct voltages, the utility supply (which has failed anyway) is automatically disconnected from the UPS and the genset output connected in its place - this happens in fraction of a second, automatically, and again, there is NO interruption to the supply to the data center - as the servers are, as always, running off the batteries, not the UPS input supply.

The UPS batteries are now being charged by the genset, and life continues as normal. Normally, gensets spin up and stabilise in a couple of minutes (our one, a 450kW jobbie on the roof, takes under two minutes). The genset should have at least 24 hours of fuel on-site.

When the ATS detects that the utility supply is restored AND STABLE, it disconnects the genset from the input to the UPS and connects the utility supply in its place. After a few minutes of stable running, the genset is switched off.

There is simply NO EXCUSE for a modern (read "last 10 years") DC to lose power the way BA did. Just unforgivable.

BA's 'global IT system failure' was due to 'power surge'

Nicko

Re: Really a power failure?

I too was wondering about LD4/LD5/LD6... been in those loads, but they are serious DCs... can't believe that Equinix would get that wrong. It's one of their key sales points...

NY4 is under the flight path into Newark - Do Equinix just happen to like building DCs near airports?

MP3 'died' and nobody noticed: Key patents expire on golden oldie tech

Nicko

> m0rt: but signal degrades every time you do anything with it, therefore you MASTER @ 24bit 96khz to ensure you don't lose any of it.

Not so. Digital is digital - you may reclock it, but there should be no bit-lossage.

Also, it's worth remembering that most studios have analogue front-ends, i.e. they are analogue through the mixing desk up to the final ADCs that convert the mixed and engineered recording to digital.

During that process, the ANALOG signal will travel from the microphones (analog) through maybe 100s of opamps (all analog - probably NE5534s or some of the more exotic Burr-Brown/TI/Linear Tech/Analog Devices ones), though a mixing deck (probably analog) where someone with expensive (analog) ears and (analog) monitors will mix it into something the producer likes, before committing it to digital.

So, the argument is about turning that hugely-messed-around-with digital representation back into something analog that you ears can handle.

I've spent many years designing amps, solid-state (linear & class D), valve and hybrid as well as a lot of speakers. At the end of the day, a technically perfect amplifier is a straight piece of wire with gain - it is possible (fairly easily) to design such an amplifier. Doug Self, one of the real gurus of professional audio design and a terrific engineer, hates audio-phoolishness and some years ago published a design where distortion levels were vanishingly small - these are known as "Blameless Amplifiers" (look them up). But they sound cold, because oddly, people like distortion of various types, specifically with speakers (which are a HUGE source of distortion) - this is also the reason people like the sound of valve amps - they sound "warm" due mainly to 2nd harmonic distortion.

The human brain & ears are infinitely complex & subtle - this is why audiology is such a complex subject. People go to enormous trouble and expense to get the "perfect" sound, but it's mainly b*llocks - it might be right for them, but it' all in the mind and won't be right for someone else. If you spend $5,000 on speaker cables, your mind will probably tell you they make a huge difference and sound fantastic; you listen to someone else's $5,000 speaker cables, and you'll probably not hear any difference.

UK.gov job ads entice IT bods with promise they will be OUTSIDE IR35

Nicko

Re: Project went to Capgemini

I was a contractor for many years, then went perm when the offer included a golden hello to cover outstanding tax liability.

I had both an IR35 and a section S660 review from HMRC and got through both, but it was a tough set of interviews - essential to have an accountant who really and truly understands these things and preps you well.

Now I hire contractors, but in my sector, the move is towards permies. Realistically, there is not a whole world of difference in job security between permies and contractors - employers have screwed down notice periods for both so can shed either pretty easily (so long as you've been there less than 2 years).

The main reason in my sector (finance) for using contractors is they appear differently on the balance sheet - permies are "fixed overheads" and contractor costs are "expenses" - this is really important for public companies that need to be seen to be managing overheads, so hiding the cost of staff in expenses is a good call, i.e. it's an accounting game.

My fortnight eating Blighty's own human fart-powder

Nicko

Re: Food is not only sustenance

I lived and worked in France for a while (not in Paris - that is a different world again).

After two months, the French director of the unit were were in called myself and the other English contractor in for a chat...

"We have a problem", he said, "you are embarrassing your co-workers and stressing me out". We were shocked - we'd thought we'd been doing pretty well - getting stuff done quickly, not sitting around waiting to be given something else to do - we went out looking for ways to fill the time and help others - i.e. a completely normal Northern European work ethic - just what we'd normally do in London or wherever...

However, it seems we were doing WAY too much, embarrassing our French colleagues (just by working normally) and stressing our managers because we kept looking for work.

So, we changed our habits - did what we had to do, worked probably at 60%, filled the rest with socializing and going round other teams in the company asking if there was anything we could do for them. Effectively a three-day week.

After 6 months of this, we were bored stupid - money was excellent, but not a way for a professional (by our or any sensible standards) to carry on.

Sure enough, as the project end date loomed, panic set in among the French - they were way behind - "Can you work weekends?". "No". "We'll pay double". "Fine". So Karen (the other Brit) and I came in on the weekends. Of course there was nothing to do because the project management was sh*te. We drank coffee and timed our day by the fresh bake cycle of the local patisserie.

Switched jobs at the end of the year. To make it clear, out colleagues were all lovely people, but their work ethic was awful.

NB. I've lived in, worked in and went to school in France - love the country, but would never ever run a business there,

King's College London staggers from outage, replaces infrastructure services head

Nicko

Re: CIO, Nick Leake

What's wrong with being called Nick?

Ghost of DEC Alpha is why Windows is rubbish at file compression

Nicko

Thanks for the memories...

Still got an AXP 433 NT4 workstation in my workshop loft somewhere - in its day, it was an absolute beast. ISTR that MS had a whole building on DEC's campus (or was it the other way round), just to make sure that the Windows builds could be processed quickly - forget not that Dave Cutler, one of the (lead) progenitors of NT, OpenVMS (or just plain "VMS" [previously "Starlet"] as it was at the start) and was heavily involved in the Prism project, one of several that eventually led to the development of the AXP. He also drove the NT port to AXP and later, to AMD architectures.

He got around a bit. The only downside was the truly abysmal DEC C compiler, which he co-authored. I had to use that for a while and it was a dog - Cutler admitted none of them had written a compiler before, and it showed.

Anyone want a lightly-used AXP-433 - was working when last used in about 1999...

Source code unleashed for junk-blasting Internet of Things botnet

Nicko

Chicken Nuggets? WTF?

The source code makes for interesting reading.... translating the embedded Russian, the Command and Control Centre prompt is....

"I like chicken nuggets"

???

A year living with the Nexus 5X – the good, the bad, and the Nougat

Nicko

Real USB-C bits and happy, year-long, user of the 5X...

Got my 5X when they first came out - agree with a lot of what's been said here, except that I put a glass screen-protector on it and a really nice slim case (not the Google one). I've had no problems at all with Nougat - phone is very happy.

Living and working in Dubai, as I now do, there is almost NO USB-C presence here - all the stuff below I bought from the UK after careful research - it's all TRUE USB-C and supports "rapid" (3A) charging, not just the "fast" charging mode which all the ersatz stuff does.

Hopes this helps those USB-C types trying to hunt down good stuff !

5X glass screen protector:

http://www.ebay.co.uk/itm/Genuine-Premium-Tempered-Glass-Screen-Film-Protector-for-LG-Nexus-5X-/331686456251

5X good quality slim case:

http://www.ebay.co.uk/itm/171946411800

Regarding charges, the new Anker kit, which is very high quality, supports USB-C correctly, including rapid charging. Anker USB-C 40W Powerport:

http://www.ebay.co.uk/itm/172246241783

A really nice Anker powerbrick for USB-C (solid aluminium case):

https://www.amazon.co.uk/gp/product/B00M0EWED0/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

Good quality USB-C to USB-C cable:

http://www.ebay.co.uk/itm/152162551240

Third-party USB-C charger that works well (this is my one in the office):

https://www.amazon.co.uk/gp/product/B019Q67ORK/ref=oh_aui_detailpage_o06_s00?ie=UTF8&psc=1

USB-C car charger - again, this is the one I use:

https://www.amazon.co.uk/gp/product/B01KFTXY8U/ref=oh_aui_detailpage_o07_s00?ie=UTF8&psc=1

HTH

Nick

Google splats more bad Android security bugs with patches your mobe will probably never see

Nicko

I'm all right, Jack!

Bought a Nexus 5X a few months back - used to have an Samsung SIII - last full update was 1st Feb. It isn't seeing these new updates just yet. 30 quid up front plus agreeing to sign up for another two years with O2 (O2 is the only network that has decent coverage out where we live).

I wish people would just stop moaning all the time. It's depressing - software is complex, especially multi-threaded, real-time stuff. It will always have holes regardless of who made it - the whole iOS/Android/Windows/Linux/whatever is just navel gazing. Get a life (and a tin-foil hat), guys (and you are almost exclusively guys). It really isn't that important.

Libertarian hero: 'Satoshi Nakamoto', government funds, the NSA and the DHS

Nicko

They've got the wrong person...

https://www.reddit.com/r/Bitcoin/comments/3w027x/dr_craig_steven_wright_alleged_satoshi_by_wired/cxslii7

Nice bit of detective work... Basically, the PGP key used on the evidence emails (as used by Wired & Gizmondo) uses cipher-suites that weren't in PGP at the time the emails were supposed to have sent. Theories vary, maybe he's a time traveller, the co-creator of PGP, or both?

Bitcoin inventor Satoshi 'outed' as Aussie, then raided by cops – but not over BTC

Nicko
Alert

Possibly all a giant fraud/mistake....

https://www.reddit.com/r/Bitcoin/comments/3w027x/dr_craig_steven_wright_alleged_satoshi_by_wired/cxslii7

Nice bit of detective work... Basically, the PGP key used on the evidence emails (as used by Wired & Gizmondo) uses cipher-suites that weren't in PGP at the time the emails were supposed to have sent. Theories vary, maybe he's a time traveller, the co-creator of PGP, or both?

Dark Fibre: Reg man plunges into London's sewers to see how pipe is laid

Nicko
Holmes

No sh*t Sherlock!

Happened long ago - when the London Hydraulic Power Company shut up shop in 1977, its had over 180 miles of iron piping under the centre of London...

Mercury Communications, part of Cable and Wireless bought the assets, including the right (as a utility provider) to dig up London's streets. Nice bit of lateral thinking...

http://en.wikipedia.org/wiki/London_Hydraulic_Power_Company

All those pipes, all filled with fibre, and with little expense as only some "tails" into newer buildings had to be laid.

GOD particle MAY NOT BE GOD particle: Scientists in shock claim

Nicko

We're doomed...

"By the way, the world may end on Friday, because there is no absolute guarantee that Saturday will happen."

http://www.hasthelargehadroncolliderdestroyedtheworldyet.com/

LOHAN test flight: Results in from Oz jury

Nicko

Re: Zeners

Only problem with using an SMPS is the resultant EMI which is not going to sit happily with the remote telemetry - however well you shield & suppress it, SMPSs can be problematic.

I'd stick with a modern LDO regulator - zeners have never been that good anyway - they are noisy, prone to wander, and can have high temperature coefficients - most are not true zeners anyway, they are avalanche diodes.

US astrophysicist Neil deGrasse Tyson: US is losing science race

Nicko

USA is not that great in science really...

Rather than just pick abstract assesments ("I'm the leader", "No, I am" etc.), apply some metrics.

A useful table for science is the number of Nobel Laureates per capita for different countries.

Using that metric, of the major winners (*), Switzerland is 3rd with 24 per 10,000 pop, the UK is 8th with 15.4 per 10,000 pop and the USA languishes in 12th with 9.9 per 10,000 pop.

What is interesting is that 9 of the top 10 countries are in Europe. So much for the USA leading the world in science - they do so by virtue of having a large (320 million) population only, not by any special aptitude they think that they may posses that differentiates them from others - indeed, compared with many European countries on this metric, they're pretty poor!

http://en.wikipedia.org/wiki/List_of_countries_by_Nobel_laureates_per_capita#Scientific_prizes

* Small countries that win one or two Nobel Prizes completely skew the figures

Mine Bitcoins with PENCIL and PAPER

Nicko

Reverse SHA256?

Anything is possible, even if very unlikely. If the NSA/GCHQ/Unit 8200/etc. had found a way to compromise some of these central tenets of modern cryptography, do you think they'd let it be known? It'd be the best secret ever.

Our LOHAN spaceplane ballocket Kickstarter climbs through £8000

Nicko

Nice dog...

Done the Kickstarter bit, but only because of your exquisite taste in dogs...

...but been following the project for a while - excellent job!

Inside Facebook's engineering labs: Hardware heaven, HP hell – PICTURES

Nicko

Re: Send reg reporters on an engineering refresher

Definitely a Bridgeport Vertical Milling Machine - no way its a lathe - Google Image it...

And, yes, using an anti-static bag (which is conductive, albeit only slightly) as the base testing a PCB is nuts.

Reg Picture puzzler

Nicko
WTF?

Re: Reg Picture puzzler

From an ex-DECcie and ex-EE (Soton Uni)...

1. An IBM 704 logic module from the mid-50s – difficult to know which actual module this is but it looks like a set of ECC82s which are in a multiplier.

2. Packard Bell 250 from early 1960s

3. PDP 12 from late 1960s – worked on those

4. PDP 8/E from the 70s – still got a manual from that!

5. DEC/Digital PDP-10, model KL-10 also known as a DECsystem 10 from mid-to-late 70s complete with its power controller

6. a few bits of core memory – used to be made by hand in the far east – the first case of off-shoring technology?

Looking at this, it looks like it comes from a Honeywell DP-516 or one of its earlier siblings – a 316? – I worked on one of these in the electronics dept at Southampton Uni in about 1976 – it also had a “drum memory” and a fantastic high speed optical paper tape reader…

They also had a Modcomp MAX4 there which replace the DP516 eventually.

7. A diode gate array – they look like IN914s or IN4148s, but could be pretty much any small signal silicon diode – diodes were (and still are) used for “wired-OR” logic.

8. This is definitely DEC again – probably a DECsystem 10, maybe a KL-10 – the colours used give it away - DEC even made their wire-wrap match the company colours…

Out of interest, to try to make some of their cabinets less boring, for some of the PDP-11 range they introduced “environmental side panels” that were garishly horrible in what can only be described as a 1970’s way…

9. We’re back to Honeywell here – when this system and the Modcomp mentioned in #6 were patched, engineers used to come in and re-do bit of the wire wrap. Them was the days… Still got my own wire-wrap tool and some spools of that nice Teflon-coated, silver plated, fine wire that was used.

10. Back to DEC PDP-8 again – These are “Flip Chips” all dating from the late ‘60s to early ‘70s - The “M” in the numbering stood for “Magenta”! There’s a surprise…M310 is a delay line (timing module), M360 is a variable delay line (another type of timing module), M113 & M115 are NAND gates, M216 is a 6 unit flip-flop (bistable), M617 is a set of 6 NOR gates. The timing modules were used to get round race-hazards in gate time – an early kludge basically. Flip chips were eventually discontinued as they were unreliable for a number of reasons, mainly due to the edge connectors – we were always having to reseat them.

11. This is obviously from a drum line printer from an old mainframe. It looks like the ones used in the ICL 1904T series units, i.e. mid ‘70s again but can’t be sure…

Still got some of this sort of just in my workshop (aka shed)...

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