A big job.
So Gary was flushed with success.
Welcome yet again to On-Call, The Register's weekly column in which we take readers' tales of odd jobs in odd places, tart them up and present them to you as a bit of light relief on a Friday. This week, meet “Gary”, who once had a trouble ticket land on his desk stating that “the PC would reset every time the customer flushed …
I thought that read 'front bump'.
I've always found this place to be mildly amusing as it drifts across my sat-nav screen when I reach the end of the M1.
Sorry to burst your bubble, but the noise cicadas make is called clittering. So Clitterhouse is, essentially, "the house of noisy insects".
(It could also be an old word for clay ... but adobes don't work all that well in the British climate, and don't make for as good a story either.)
Beer. Because what else could follow the above, especially on a Friday.
Over 30 years ago I worked for a company that supplied minicomputer systems for pathology labs in hospitals. I was on-site at one location, where the customer had complained of the system continually restarting itself.
I was staring blankly at the machine, wondering where to start, when there was a "whump!" that was felt rather than heard, and the lights flickered.
"What was that?", I said.
"Oh, just the X-ray department next door".
Problem found!
In an existence before that, we used to have similar problems on our micro development kit. We noticed that they got more frequent around 5pm. We eventually realised that it was due to the lift in the building.
I worked for a radio station and in the studios you try and eliminate external and internal noise. So everything that can be soundproofed is and things that couldn't be were stuck in a rack outside the studio. They had good air conditioning and were generally kept cool which obviously suited the electronics. We had a new station which was going to be mostly recorded shows being broadcast from the building and a new studio was built for the existing station. The old studio was then going to be used for recording the shows on this new station. However when they came to use the old studio they complained that main computer was shutting down on a regular basis. This was used for recording the voice of the DJ into the station playout machine and that had never happened before, it had been rock solid.
It was one of the computers that we couldn't place outside the studio and so required the studio to be empty whilst we looked into the problem. It was a real mystery because the problem was only happening now and we couldn't work out what had changed since the legacy station had moved out. There was now less use of this PC instead of more so why it was suddenly crapping out every so often was head scratcher. It didn't happen when we were checking the studio over even after a period of hours and we looked at everything we thought could be the cause.
It was only when we were watching a show being recorded everything slotted into place. The fan on the PC wasn't silent enough so we'd set it up to switch off when the microphone fader was up (i.e. people could hear you on air / the recording). We realised that the fader stayed up all the time as they were just recording the bits between the songs. So after a period of time the thermal trip switch would cut the power to the PC as protection because it wasn't getting any cooling from the fan. Previoulsy it wasn't a problem because the fader would be down and the fan on during the songs and adverts. Once we'd worked that out we disabled the mic fader link to the fan and just let it run continuously.
Almost 30 years ago I had a CRT monitor on which the picture would, at regular intervals, get twisted and show a definite tilt to one side.
I was on the point of sending it back as faulty when I realised that the hospital's MRI scanner was directly above me, 2 floors away.
When I went to university many years ago, I was able to buy my first PC, a 286 clone. Just, a morning while I was writing and testing some Matlab code, the PC rebooted suddenly (losing a lot of work). And it did again in other days, always when working in the morning. Only after a while I noticed it happened when the cleaning lady was turning on the vacuum cleaner...
Mainframe O/S occasionally crashed and the customer sent us the resulting post mortem dumps. It had the whiff of electrical noise about it - so we arranged to go in when the engineers had their big weekend maintenance session.
While the engineers did their peripheral maintenance tasks we tried a few experiments. We knew from experience that the mainframe's engineer's panel - even when stopped - would show random changes if a severe noise problem existed.
Card reader - no. Card punch - no. Load a tape drive - after a few tries - bingo!.
Very pleased with ourselves we waited until the Chief Engineer was free a few minutes later so we could demonstrate it was a hardware problem. When he came over - the problem wouldn't happen.
So we asked the question - what has changed in the last few minutes? Nothing - except the engineers had lifted a floor tile to install a cable for an additional new tape deck. Put the tile back - and the problem was able to be recreated.
The space under the tiles was jam-packed with cables - one for each tape deck. Each cable had a metal box some distance away from the tape deck. The metal box for a new tape deck installed the previous week was sitting high on all the other decks' cables. It was high enough to just touch the underside of the floor tile above - but not high enough to stop it going home properly.
The false floor was an unusual design. Instead of corner "mushroom" supports - it was a lattice of steel bars. The floor tiles were backed with an unpainted steel sheet. That had connected the lattice to an unpainted area of the tape deck cable box. The lattice was grounded to the building wiring for electrical safety - and the result was the computer room's "clean" earth was being connected to the building's "dirty earth".
Back in my Central Line days with London Underground in the mid 1990s we had an intermittent earth that screwed up the signalling for about a month. As it was at Marble Arch it caused havoc with the service. Always used to happen in the AM peaks.
The whole area was cleared of any scrap metal etc, engineers on site overnight, nothing found. Points on the crossover given a thorough going over etc.
Eventually the cause was found - there had been a broken chair screw (a screw that holds to the sleeper the thing that holds the rail) in the past that had snapped below the surface of the sleeper. A new screw had been wound in on top of the old one - pushing it out of the bottom of the sleeper. Over time, the track bed had settled a little, thus meaning that the old screw, only under the weight of a fully laden train (hence the AM peak), just made contact with the iron tunnel segment. As the old screw was in contact with the new screw, that in contact with the chair, and the chair in contact with the rail - through which the current controlling the signalling runs, Bingo, a lovely hidden intermittent earth.
There was a core-based mainframe - you know those memories made up of very small magnetic cores arranged in grids and flipped by two crossing circuits. Lots of fun problems with those such as young programmers burning up a core by flipping it constantly on/off....
Anyhoo, this story is about the periodic rebooting of said mainframe. For many months on a not-regular basis the primitive system would sigh and give up its ghost. All the field engineers in the kingdom couldn't determine why this was happening. Replaced cores, replaced CPUs,, etc.
Then one night someone was standing next to the memory box and heard this whoosh, followed by the death rattle. Looking up at the tube overhead that emitted the whoosh he asked what was in the tube that would make the noise. It was determined to be one of those fancy pneumatic tubes used for sending priority messages. The passage of the carrier overhead was enough to induce a magnetic field in the cores.
Ahhh, technology.
Way back in the dim and distant 80s, I did some work for BP Minerals who had an exploratory base-station in norther Norway, just up from Trondheim. Back then we were using DEC Rainbows to download and process magnetometer data which was then saved to 5 1/4" flooppy disks. The field crew kept reporting that their floppy disks were being corrupted and they were loosing the data. These very early PC-alternatives didn't have a hard drive, just 2 floppies - one was the system drive with a CPM disk and software we ran the other was the data drive, so loosing data meant the magnetometers became unusable as we couldn't clear the data from their pathetically tiny memories.
We thought that maybe the floppies had been corrupted by the airport x-ray machine so we put them in a metal box and wrapped them in tin foil... didn't work... So I, as the programmer of the data processing software, got sent out for a week to work out what was going wrong. This was April and the snow was still on ground and I got to rid a skiddo to the log cabin in the middle of nowhere on the edge of the arctic circle to spend a week in a log cabin with a PC and 2 Geophysicists. On the first day they went out surveying and I sat with the PC checking everything I could think of. There was an electric wall heater on a thermostat/timer and I noticed that whenever it switched on the lights flickered a bit and the fan on the PC changed pitch... Lo and behold disk errors started to appear... Quick trip back to Trondheim to pick up a rectifier and bingo no more disk errors...
From that day on it became part of the standard field kit...
I believe it's pond side slang for a device that corrects brown outs. I did have a couple that came over with some kit from the states many years ago, but I never used them because... 240V. Huge great transformer it looked like, must have weighed 15kg, with a couple of black boxes slapped on the ends, one of which contained a diode pack that looked like it could have rectified the entire National Grid and a capacitor of lethal dimensions.
Words for technological devices mutate over there. I had so many customers come into Radio Shack wanting new batteries for their convertor. Now a convertor is a cable TV box, but they call the remote control for that a convertor. And there are a dozen other examples of inaccuracy in the common parlance for things electrical.
--EDIT--
Ha ha ha. Brown outs.
No. A rectifier is a collection of diodes in these parts, same as in Blighty. Not sure what you are talking about, but it sounds vaguely like an inverter. Why it should correct for brownouts is anybody's guess.
We have 240V here, in nearly every home. Yes, most small appliances run on 120V ... However, most homes have two legs of a generator's output, called L1 and L2. Each provide 120V when you connect across the neutral. But if you connect L1 and L2, you get 240V ... Heavy electricity users, like clothes driers, water heaters, ovens, air conditioners, some pumps, etc. use 240V. Yes, that's simplified. Intentionally.
Never heard of a set top box called a converter. It's a set top box.
Never heard of a TV remote called a converter, either. It's a remote (control).
That device sounds suspiciously like a ferroresonant power conditioner... Dirty great lump of transformer with capacitors and 'magical' connections that prevents the changes in line voltage from reaching the connected equipment (for a second or two) by storing power in the caps/inductors. They act also like a very short term UPS (1 second max, istr)
Damn good things, but weigh a ton (sometimes literally). Makes a noise like someone twanging a plastic ruler on the edge of the desk when you switch it on.
I can see them being called 'rectifiers' because they rectify power problems?
Also they'd not be transferrable between left and rightpondia, because of the different frequency, they're resonant at one, and only one frequency.
Also: (rightpondian here for clarification). Cable tv set top boxes are called converters, officially. The old Jerrold general instrument boxes were labelled as such. More of a technical term that a consumer one though.
"Also they'd not be transferrable between left and rightpondia, because of the different frequency, they're resonant at one, and only one frequency."
A lot of them could be tuned by changing caps around.
They were scary things, using saturated cores and dissipated a _lot_ of heat (useful in the tropics if you needed to keep your printer paper dry)
Yes, "That device sounds suspiciously like a ferroresonant power conditioner." I found one of these in the HVPSU of an Austrian designed TV transmitter/transverter that I installed in the fairly peaceful and very beautiful KSA/Yemeni Asir border area in the '80s.
the ferroresonant device was 50Hz, but the previously installed TV repeater station genset was 60Hz, I was able to fudge it once I had worked out why the tetrode EHT fuses were popping! (for some reason I ate mostly parmesan cheese whilst doing this maintenance as the local market of horribly beweaponed ghat growing tribes sold whole round cheeses) The UHF driver amplifier was also multimoding as a second fault, and had to be filled with a lot of aluminium foil inside a plastic bag, to try and dampen down the feedback/gain/sprogs, all this whilst trying to breathe at 3500 metres asl, on top of Jabel Fayfa.
Never heard of a set top box called a converter. It's a set top box.
It appears to be a holdover from when VHF-only TV sets had to have a downconverter box added when UHF transmissions were introduced. And for viewing DVB-x on a conventional analog telly you'd also need a (rather convoluted) D/A converter.
from when VHF-only TV sets had to have a downconverter box added when UHF transmissions were introduced.
Converters long predate that . The original ones were added to single-channel TVs so that they could receive Band III ITV as well as the original Band I BBC. My grandparents had one.