* Posts by Stoneshop

5954 publicly visible posts • joined 8 Oct 2009

Maplin shutdown sale prices still HIGHER than rivals

Stoneshop

Part of it

Its amazed me that the more electronics has become a fabric of our culture, the less stores are commonly available. Maybe this goes hand in hand with the dumbing down in society, and the lack of desire to understand how things work.

Well, in most cases when you think you might be able to fix the device, armed with the level of knowledge you expect will be required, it will furiously resist being opened up, then, if you manage to overcome that, will even more furiously resist troubleshooting due to lack of documentation and adequate test gear, and finally, having found the problem component despite the hurdles posed by the previous steps, it will turn out it's a HXC42276 rev.2bc made by Yum Cha Super Victorious Enterprises, a 169-pin BGA chip. The only three references to this part found on the Internet are your own search for this item, and two 'component suppliers' who claim to be able to sell you the HXC42276 rev.2a (a 144-pin PGA), only in quantities of 1000+ and for an undisclosed price, but with a lead time of 48 hours which they similarly claim for all the parts they sell, which includes OC72 transistors and AZ3 rectifier tubes (all brand new, and again in quantities of 1000+ only).

In other words, the gigantic proliferation of special-purpose ICs has made it as good as impossible even for a decent brick-and-mortar store to stock the parts that could satisfy the requirements of repairing common household electronics. Unlike 30 or more years ago.

Rant launches Eric Raymond's next project: Open-source the UPS

Stoneshop
Devil

Re: Lack of clue

"I suppose it is tempting, if the only tool you have is a hammer, to treat everything as if it were a nail."

-- Abraham Maslow, The Psychology of Science, 1966

I suppose it is tempting, if the only nail you have is ESR, to treat everything as if it were a hammer.

Me, 2018.

Stoneshop

Re: Good luck, will be nice to see the third iteration

what's good for charging SLA batteries may not be suitable (or desirable!) for LiPO. What a LiPoFe4 stack would find usable would be unusable for an SLA, or NiCad, etc.

So you would want a modular approach, selecting the appropriate charger for the various battery chemistries and the selected capacity. Different chemistry would also mean a few different parameters to monitor (cell temp, charge/discharge current and voltage for all of them, but with different warning thresholds). Then some people would want an 110V inverter (and charger), some 230/240V, and others an ATX-like or SELV output. So modular again.

In all, I myself would go for an existing UPS of the appropriate config and capacity, then bolt on a monitoring circuit that covers the appropriate parameters, replacing the manufacturer's crap. So, reinventing only that part of the wheel that apparently needs reinventing, leaving the rest, including the parts dealing with mains voltages, to (a selected few) of the existing manufacturers.

Stoneshop

Re: server based UPS

The one bit that stuck with me was the claim that 90% of power disruptions last less than two seconds(I'm assuming they were specifically referring to data center disruptions).

The VAX9000 had a power system that consisted of a 280VDC bus inside the system cabinet feeding the 5V/-5.5V/12V/whatever PSUs, supplied from a power front end that took about 2 19" racks worth of space. That held a transformer, rectifiers, control circuitry and a serious number of electrolytic capacitors. This was to ride out such short glitches (IIRC it was good for ten seconds or so, definitely not enough to shut down the system)

Stoneshop

Re: Who will compile my open source UPS?

To specialists. Someone which no clue about battery technology (architect, lawyer, dentist, astronomer, you name it) will have little to no chance translating the US specs to something locally available, and the US project brains can't make suggestions because they can't know what is or isn't available in every country/continent.

But there will be knowledgeable people from other regions who will add to this project[1], as with most open source stuff (both HW and SW) that requires some form of localisation, and a dentist from Dubrovnik would just need to drill down in the list of country-dependent modifications to get the right circuit board plus bill of material, as would an architect from Abidjan.

[1] or fork it, as there are people who may well be disinclined to cooperate with ESR and Jay Maynard. For, in my view, very good reasons.

Stoneshop

Re: ATX connector?

Because someone is bound to try and connect the ups directly to a motherboard's ATC socket...

And if the UPS output can supply the voltages and currents an ATX mobo requires, what would be the problem?

"I wasn't suggesting replicating the ATC interface, just providing the voltages the ATX interface supports."

With an approach like that you actually want to be able to hook up such an ATX-UPS directly to the motherboard, minimising cable and connector losses.

Stoneshop

Car batteries? Why not have an option for a truck (semi type) battery since they're bigger and have more capacity? So the electronics could once acquired, could be used with the user's choice of batteries

At the very least you would want to adapt the charging circuitry to the battery capacity: lead-acid batteries want to be charged at 0.1C (their rated capacity in Ah), so it's not quite one size fits all.

Stoneshop

Re: Specs

Have the batteries located where the PSU is currently located.

You can't use all of the PSU's space for batteries, as you still have to convert the battery voltage to the other voltages used in the system for which you need about one-third of the space a standard PSU takes. For low-power systems (Mini-ITX) you can use PicoPSUs of the appropriate rating which run off 12..18VDC, so easy enough to run off a battery with a charger attached. But for larger systems, especially with beefier video cards, those won't cut it

I'm not sure if for those larger systems the reduction in conversion losses is worth it regarding the various stuff you need to do it this way.

Stoneshop

Re: ATX connector?

Fairly sure your monitor and network switch don't run off 240v. Mine have external power bricks.

My server is headless, and the network switches do run off 230V.

The proposal was ATX voltages, not ATX physical connector.

Given the average motherboard power consumption you would need a multipole connector using several pins per voltage not unlike an ATX connector (so why not an actual ATX connector with some auxiliary ones for whatever else you're hooking up), or a connector capable of that 300VA total, one pin per voltage, so rather beefy. And then some converter cable to adapt that to an ATX connector plus again some auxiliary universal ones, as that will be the most common use case. Six of one, half a dozen of the other.

Stoneshop

Specs

That's why I am suggesting that the server manufacturer should provide a built-in UPS function.

Which would require sufficient room inside the server case for the batteries. And what runtime (i.e. battery capacity -> battery size) would you then aim for?

Never mind that rackmount servers tend to be rather stuffed.

Stoneshop

ATX connector?

The point is that by having the UPS delivering the standard ATX connector motherboard voltages, you can avoid the double conversion we currently have where the UPS delivers 240v to the computers PSU for it to convert into ATX voltages.

So, what about people (such as me) who want to power their server plus a network switch or two? And the DSL modem?

Also, for an UPS with an ATX connector fitted you would have to install it inside the computer case. Would there be sufficient room for the battery, and a free drive bay where you can put the monitoring panel? There have been PSUs with a battery backup fitted, but they never went past a few minutes of runtime. Save and shutdown gracefully, and that's it. The last time I had a power cut my setup rode out the entire four hours.

Stoneshop
Boffin

UPSs lack the kind of sensor information that protected car batteries, Raymond wrote

He thinks car batteries are protected? Shows how much he knows about hardware.

EV batteries, which are some flavour of Li-ion, are indeed monitored and protected (they have to be, by their nature), but that's still a minuscule fraction of 'car batteries'. Conventional car batteries (lead-acid, trend has been towards SLA for some time now) aren't.

Stoneshop
Windows

Re: Designed by programmers

All consumer devices should be designed by programmer-lead teams,

Let me introduce you to the 'programmers' I have to deal with.

UK's air accident cops are slurping data from pilots' fondleslabs

Stoneshop

Re: There's a thought....

All I was proposing was something to record some information rather than a total absence of any kind of recording at all. Preferably in a package that's cheap (compared with a Black box) and rugged enough to survive a crash.

Several gigs of flash, a GPS, an accelerometer, air pressure sensor and a microphone, plus a battery wouldn't need to be larger than a box of matches. With a robust casing you'd be well underway to provide a bit of a black box for light aircraft. Even when GPS and the pressure sensor don't provide absolute accuracy, an investigator arriving at the scene would register the exact position so that the offset with the recorded data can be calculated. Same, to some extent, with the pressure recording. And a microphone will allow both the pilot's voice "Oh bother, the left wing is gone" as well as engine noise (revs, sputtering, cutting out) to be recorded. While the AAIB can determine that, for instance, the engine cut out shortly before the crash, the recording would help to set a timeline: was it five seconds, half a minute or two minutes?

Europe is living in the past (by nearly six minutes) thanks to Serbia and Kosovo

Stoneshop

Re: For those who wonder...

I have got my own Solar power system, which exports anything I don't use locally into the Grid; and I've been considering installing a system with some big batteries and a smart charger (probably Raspberry Pi-based); which will continuously read the telemetry data from my Inverter to determine how much power is available for charging the batteries, and set the charging current accordingly so as only to use Solar energy, and no energy drawn from the Grid, for charging the batteries.

I'm contemplating something similar, except that initially I'll be going to install an electrically heated boiler (or two), powered if there's excess power from my panels. If that happens to become depleted of thermally enhanced H2O, then a valve will switch the demand to the hot water supply tied to the gas-powered central heating system. Once that's done I may start looking into electrical storage, although an electric vehicle might well cover that, in a way.

For your setup you're basically building a big-ass UPS powering (part of) your house, going into bypass mode if its batteries are down or load demand exceeds its capacity, and being charged off solar.

The Solar system does need the grid connection, though, because it has to have something to lock against -- and it stops producing AC power altogether if the grid connection is lost. This is for the protection of any people working on the line

The manufacturer of the inverter I have fitted (SMA) offers a setup that turns a standard mains-tied inverter into one capable of 'island' operation (they also have 'island'-mode inverters, but those are meant for fully mains-independent operation), one component of which is a relay fitted in your incoming mains feed. I expect that one's utility co. will want such an installation to bear all relevant certification marks and then some, not just someone's Arduino-controlled flimflam.

Stoneshop

Re: 240/230/220V

Firstly, these are not things that they mass produce and put on the shelf, they tend to be made to order and different areas have different specs anyway. In any case, the difference in winding between 230 and 240V is not major.

The really big ones are not mass produced[1], but the transformers used in local substations are used in numbers that warrant small-series production. And looking at the storage yard of one of the regional network operators that happens to be nearby, there are a few transformers in there. The largest ones you could just about load on a flatbed truck without then needing 'Transport Exceptionnel' escort, to give you an indication of their size.

[1] I occasionally go past the Smit Transformatoren factory, and they usually have four to six of those, almost always all different, standing outside being readied for shipment. Impressive stuff.

Stoneshop

Re: 240/230/220V

It didn't. They changed the % limits for Mainland Europe, GB, NI and Ireland. It's mostly 240V in UK, 220V in Germany

Nope. Germany, as well as the rest of continental Europe, is at 230V now.

Equipment marked CE has to work in any EU electrical supply, though it MUST have the local standard of plug, if it plugs in.

That's why non-grounded (doubly insulated) equipment is fitted with Euro plugs: two-prong plugs that fit the various sockets in use.

Stoneshop
FAIL

Re: For those who wonder...

Too lazy to prove it now, but it would not surprise me if it happened all over Europe.

Nope. Domestic DC was uncommon, though it has been in use in some places. In the 1960's there were still locations that had DC as well as AC, for instance the Danish island of Fanø.

If then Britain is alone with DC then, well, how surprising, not.

Only the HV interconnects to France are.

Of course there was this fight about efficiency regarding the electric chair in the USA,

It wasn't about efficiency, it was about Edison (DC) versus Tesla (AC), with Edison 'proving' that AC was more dangerous by demonstrating electrocutions using AC.

Stoneshop
Boffin

Re: Some might call that "taking back control"

Obviously it will be necessary to build a wall around Europe to keep them in their place

ITYM "wall around the Continent". The UK, and Ireland, will be part of Europe until some serious tectonic action occurs across the North Sea.

"Fog in Channel, Continent isolated"

Auto manufacturers are asleep at the wheel when it comes to security

Stoneshop

Re: What motivation car manufacturers ?

I would guess that the motivation will be when Insurers sue Manufacturers.

They won't.

Insurance premiums are calculated based on the probability of the insurance co. needing to pay out, and this probability depends on a couple of factors such as the area you live in, yearly mileage, your personal claim history and, indeed, make, model and even colour of the car. If it's one that's easy to steal and (therefore) popular with the car-nicking crowd, premiums will become a factor in not buying that car, and the manufacturer will either drop the price or fix the problem, or in an extreme case drop the model.

Stoneshop

Re: What motivation car manufacturers ?

Would you buy the same model car if your previous vehicle had been stolen ?

Depends. If the theft was directly attributable to the manufacturer's sloppiness[1], then yes, probably. On the other hand, one may have a particular preference for exactly that type of car (because of size, economy, handling, loading capacity, ergonomy or whatever else), taking any downsides as they come.

[1] which in the EU may well get the manufacturer in a spot of trouble because of consumer protection laws.

Stoneshop
Mushroom

Writing shite

Because they're not directly affected by their software failing.

It has been like that from the moment software developers didn't have to get out of bed at o'dark thirty because their crap fell over, as there were sysadmins on duty to isolate the developers from those little inconveniences. And a chewing-out the next day won't ever be quite as educational.

Stoneshop
Boffin

Blinkered

“The only difference is when you have a problem with computer it won’t affect your physical security"

One word: Therac-25

And of course the proliferation of electronic locks, fire and intrusion alarm systems and such will mean that, while maybe not directly attributable to such a system, people have gotten hurt or died because of those systems failing. And this is not going to change, ever.

Facebook Onavo Protect doesn't protect against Facebook

Stoneshop
Big Brother

VPN

Isnt that what SSL / HTTPS is for?! VPNs are generally for privacy when used to access the internet. Tossers.

HTTPS and SSL encrypt the traffic in your session with that particular site, but stuff like DNS lookups go out in the clear so everyone can see that you're visiting www.rule34.com. And with a bit of trickery the inattentive user might actually be visiting www.nottherealrule34.com instead.

VPNs establish an encrypted tunnel to what should be a trusted endpoint, from which your traffic goes to whatever sites you fancy.and no-one looking at the traffic between you and that endpoint should be able to determine what you're up to. That endpoint, however, is basically representing you, and you have to trust it's dealing with the information it can gather (connection logs, DNS lookups etcetera) in a way that you approve of.

Facebook is not on my list of entities I trust. In any way.

Suspected drug dealer who refused to poo for 46 DAYS released... on bail

Stoneshop

Re: Ah well...

Pu-Ehr tea? About maybe twice the price of a midrange common Assam. You're probably thinking of the several years old variety which can indeed be rather pricey, but you don't need that. And checking around, even the 15 year old stuff is way under a tenner for 100g.

So even that is definitely cheaper than keeping the guy in custody for nearly seven weeks, even if you have to treat him with a gallon of the stuff before his sphincter surrenders.

Stoneshop
Flame

Re: Ah well...

There is a point when Indian police approach of force-feeding bananas under similar circumstances starts to seem more humane.

I have it on good authority that a solid mug or two of Pu-Ehr tea will have the same effect.

Ocado to stock cannabidiol-infused water

Stoneshop
Coat

don't expect a quick fix for whatever ails you

... written by Richard Speed

Hackers create 'ghost' traffic jam to confound smart traffic systems

Stoneshop
Boffin

Re: Traffic flow

CSMA/CD

Problem is that a lot of traffic doesn't gracefully back off in case of a CS, interpreting MA as My Access. And CD, while working in a way, has rather a large time delay between the actual C and any traffic rerouting required, never mind that the involved cars only rarely manage to get retransmitted.

Stoneshop
Go

Re: Hackable sensors not really necessary...

but instead of flashing up your speed as a warning, they flashed up the speed you needed to drive at in order to get through the next set of lights on green.

Quite common in a fair part of continental Europe, on larger roads in/through a city. One light has a green wave signalling, indeed, a green wave, a second has the advised speed. Some even have a third light with a lower indicated speed for the case that the lights at the next crossing are still red but will turn green any moment now, and slowing down a bit will let you catch the wave

Oh honey! Oxfordshire abuzz with reports of a MEEELLION bees stolen

Stoneshop
Go

Re: Beesmode

Are they African or European type bees for example

Just check how many are needed to lift a coconut.

Stoneshop
Pint

Re: Bees with ...

but personally I feel that "Beericane" would be the name of the film

I expect a lot of people to misinterpret that.

Paul Allen's six-engined monster plane prepares for space deliveries

Stoneshop
Boffin

Re: Any other uses?

It's going to be very restricted regarding places to land, simply due to its size. So turning it into a generic cargo carrier isn't going to fly, I think. The Antonov 225 and 226, and the C5A are way less picky in that respect.

Stoneshop
Windows

Re: control

I wondered if it was for when the pilot and co-pilot had had a row.

Or one of them has a bad case of body odor.

Drones replace models on Dolce & Gabbana catwalk

Stoneshop
Coat

Re: disappointing

I assumed the drones had a clothes hanger on them with clothes on it,

In that case the only difference with live models would have been the buzzing sound.

Fender's 'smart' guitar amp has no Bluetooth pairing controls

Stoneshop
Mushroom

Re: Jazz 2.0

Good live bands have always responded to the audience.

As do bad live bands. By erecting projectile-resistant fencing at the edge of the stage.

Only mediocre live bands just play straight on.

Stoneshop

Re: I will not hear a word said against Fender

Why they didn't use the heavy duty B connector used on professional gear is unknown.

And even those are pretty crappy.

For real roadie-resistant connectors Neutrik has USB, RJ45 and several other not-known-for-their-durability computer connectors, housed in their signature XLR shells. With matching chassis parts, of course.

We all hate Word docs and PDFs, but have they ever led you to being hit with 32 indictments?

Stoneshop

Re: There's a worrying implication

Maybe when banks used Line printers and SOHO users had a daisywheel or MX80 DMP.

They were already switching to high-speed laser printers when I was in FS, so around 1990. And I mean high speed. I was told the (Siemens, IIRC) beast in the basement at a payrolling provider did triple-digit pages per minute. They were doing the payslips for a significant part of the Dutch workforce at the time, which would amount to somewhere between one and two million statements printed per month for just that one task. Banks would have similar machines, probably multiple even.

The, ehm, paper tray took what appeared to be shipping pallets with specially packaged paper (couldn't get a close look, I was working on a VAX in a different part of that basement, fenced off from where the printer was, but the sysadmin told me a few things about it)

Stoneshop
Devil

Re: Sympathy for the devil

You're going to end up making me sympathetic to Trump's team, and that's worrying.

Just remember that the devil is a man of wealth and taste. Unlike the Orange Turnip.

Stoneshop
Pirate

Re: Well, you see, now there's the problem...

You just hire Arthur Andersen.

Accenture nowadays. With that stupid accent-like sign over the capital A.

The other large accountancy firms are probably just as good, eh, bad.

Stoneshop
Holmes

Re: What

Ah yes, Mueller is being a good little tool for the Clintons.

Hmmm. Interim Deputy Attorney General under Bush I, then nominated for the position of FBI director (also under Bush I) and appointed shortly after. Being interviewed by Trump[0] for (again) the position of director of the FBI, then appointed special prosecutor by Deputy AG Rod Rosenstein. Doesn't add up to being a Clinton tool, really.

[0] doesn't actually count for much, given the quality of the Orange Turnip's picks.

Stoneshop
Headmaster

Re: Just Wow

With this administration we are all doomed.

To be pedantic: neither Gates nor Manafort are, or were, part of the administration, just part of the campaign. But looking at the actual members of the administration, they appear to be selected on the same criteria, credentials and relevant experience as Manafort, Gates, 'coffeeboy' Papadopoulos, 'obvious anagram' Reince Priebus and the others who have already, eh, left.

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

Stoneshop
Headmaster

Comprehension problem, indeed.

The government can no longer control the interent.[sic]

Ah, you mean the US government can no longer control the US Internet. With 'US Internet' actually being the US providers.

Like I said, a problem on your end.

Stoneshop

Re: A No-Weapons Policy. That's Nice...

Plus nine of them took over 150 at once (OKC's toll)

Those would be?

Stoneshop

Re: A No-Weapons Policy. That's Nice...

How many people do you think have died in mass shootings since 9/11?

1875 to date. But even if the count was 2999 the gun nuts will proclaim that it's still lower than the WTC death toll.

Data from the Gun Violence Archive reveals there is a mass shooting – defined as four or more people shot in one incident, not including the shooter – nine out of every 10 days on average.

Stoneshop

Re: Face it, dweebs

You lost the internet.

[does a few traceroutes and speedchecks]

Appears to be working just fine TYVM.

Looks like it's a local problem at your end.

Stoneshop

Re: how heavily outgunned Vietnamese

and the side whose soldiers are more expendable has a big advantage in close combat..

Plus the advantage, both physical and psychological, of fighting on home ground.

Stoneshop

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

If gun control is a precursor of communism, how come I can count the number of communist states on one hand? China, Cuba, Laos, Best Korea and Vietnam

You might want a six-fingered hand soonish then, as Venezuela is set to join their ranks.

(One may consider them effectively communist already)

Stoneshop
Facepalm

Re: A No-Weapons Policy. That's Nice...

Remember, the worst nonmilitary massacres in American history didn't use guns.

Just that for some reason, those don't happen quite as often. By far. And neither do they add up to the number of casualties that gun violence does.

Stoneshop
Devil

Re: Ajit Pai,Vice President Mike Pence, Rush Limbaugh, and Sheriff David Clarke

Oh, I would.

But only after preparing myself by way of an extremely solid meal of Chilli con Carne, in order to be able to release the most magnificent bung blast.

Stoneshop
WTF?

As is Charlton Heston

Who, according to a biography heroically defended the Aleutian[0] Islands as a gunner on a B-25 during 1944 and '45, facing "extreme weather" that "was as dangerous as enemy aircraft." He also "slipped on a patch of ice and was run over by an ambulance."

[0] Japan actually invaded the Aleutian islands Attu and Kiska in June 1942, but they were recaptured in 1943, before Heston enlisted.