Test Equipment Anonymous (TEA) : Discussion and Group Therapy Thread

[AVGresponding]

gotta' admit that you brits did some limited episode series that were freakin' great.

"I Claudius" and "Danger UXB" come to mind.

had long given up hope that we would ever do similar.......until "band of brothers" came along.


edit on second thought......wasn't the red headed guy who played cpt winters actually a brit doing a 'merican accent? I think of him every time we drive up to hershey to see swmbo's glaucoma doc and cross the "Major Richard Winters" bridge. as bridges go it is pretty crappy.

Yes, Damian Lewis

[tggzzz]

gotta' admit that you brits did some limited episode series that were freakin' great.

"I Claudius" and "Danger UXB" come to mind.

had long given up hope that we would ever do similar.......until "band of brothers" came along.

I have I Claudius on DVD Never bothered with Danger UXB.

American broadcasters have re-discovered the limited series on their streaming services, e.g. The Queens Gambit, Wednesday, The Diplomat. The usual (small) proportion are extremely good.

I suspect that, as with the BBC, that is because there is no pressure from the advertisers to create ever more episodes until the content becomes homeopathic. Yes M*A*S*H, I'm looking at you

There's the added benefit that there's no requirement to stick to a specific length transmission slot, so in addition to the usual 42 minute programs (i.e. content:crap is 2:1), you can find 15min, 17min etc etc. That's a great improvement; short stories have been a lost art form since the demise of magazines and word processors became available.

[nixiefreqq]

"I suspect that, as with the BBC, that is because there is no pressure from the advertisers to create ever more episodes until the content becomes homeopathic. Yes M*A*S*H, I'm looking at you"


probably why we still praise the quickly canceled "firefly" . if they had killed off "red dwarf" after 8 episodes would we still be going on about its cleverness and production quality? (ok....maybe not).

[tggzzz]

"I suspect that, as with the BBC, that is because there is no pressure from the advertisers to create ever more episodes until the content becomes homeopathic. Yes M*A*S*H, I'm looking at you"


probably why we still praise the quickly canceled "firefly" . if they had killed off "red dwarf" after 8 episodes would we still be going on about its cleverness and production quality? (ok....maybe not).

I didn't pay much attention to Red Dwarf, but I was under the opinion that it took a series (or two?) to "settle in" and decide what it was about. OTOH I'm pretty sure that it did go on too long. Skimming wackypedia, it appears that one of the writers left after series VI, and that there is differing opinion about what happened afterwards.

But <100 episodes is mere chicken feed...

There's a weekly radio programme with >3400 episodes (do the arithmetic!), but only 2492 are available on iPlayer https://www.bbc.co.uk/programmes/b006qn ... des/player , https://en.wikipedia.org/wiki/Desert_Island_Discs

Or the >20,000 episides of "an everyday story of country folk": https://en.wikipedia.org/wiki/The_archers

If you prefer to stick to TV, then

• current affairs 1233 https://en.wikipedia.org/wiki/Panorama_ ... programme)
• science, the longest with the same presenter (56 years), still running https://en.wikipedia.org/wiki/The_Sky_at_Night Patrick Moore was the archetypal boffin; gave a talk at my school once
• twice a week live childrens' programme TV, 5294 episodes https://en.wikipedia.org/wiki/Blue_Peter Caused a stink this month when it was announced that it would no longer be a live broadcast
• quiz show 1792 episodes; some of the contestants have since become very well known https://en.wikipedia.org/wiki/University_Challenge
• soap 11,526 episodes https://en.wikipedia.org/wiki/Coronation_Street

And then there are mere whippersnappers such as Dr Who, which started in '63.

[mnementh]

I can't remember the series. It was about 1958.

I remember those other series including Lost In Space and Voyage To The Bottom of The Sea. There are some episodes on Youtube. They seemed great at the time but crude and dated now. I always thought Space Patrol was silly. Star Trek wasn't much later and first appeared in 1966 and I believe 1969 in the UK. I recall it was inspired by The Forbidden Planet, which was about the first sci-fi film with a proper budget and special effects. The Forbidden Planet was inspired by The Tempest. That robot turned up in a few productions. It must have cost a fortune and they wanted a return on their investment. The usual robot in Lost in Space was based on Robby but was noticeably different. Robby did put in a couple of guest appearances.

There's a Wikipedia entry on Robby the Robot with lengthy filmography.

The robots were similar because they were designed by the same man, Robert Kinoshita. His art direction was influential in many aspects of 60s-80 American TV and cinema; from Forbidden Planet and Lost in Space to Hawaii Five-O and Barnaby Jones. A varied and interesting CV, that man.

A lot of the visual cues that Americans of the "SciFi Age" of broadcast TV take for granted... literally ingrained in our "cultural subconscious"... are a result of this man's vision of "the future".

mnem
Yes, you may touch it.

[mnementh]

"I suspect that, as with the BBC, that is because there is no pressure from the advertisers to create ever more episodes until the content becomes homeopathic. Yes M*A*S*H, I'm looking at you"


probably why we still praise the quickly canceled "firefly" . if they had killed off "red dwarf" after 8 episodes would we still be going on about its cleverness and production quality? (ok....maybe not).

American Idol (and the Gold Rush" production mentality that ensued thereafter) killed Firefly, not the quality of the program material, which was definitely above-average. If it had been allowed to continue, it would've been as highly regarded as Bab5, for the same reason: Its creator had a fully realized vision for the show, with a beginning, a middle and an end.

Even Bab5 suffered from the "money-grubbing executives" disease; the story as written was over after they told all the old ones to fuck off. But the extra season did at least give the primaries a chance to play around a little bit and have some fun with their roles, and as a viewer I appreciated the chance to say good bye to old friends as they rode off into the sunset.

As for MASH... I grew up with it on TV... and while I generally agree it lasted longer than it should have, the addition of Winchester made some of the best comedic moments on TV. There was real professional chemistry between David Ogden Stiers and Alan Alda; the slapstick and buffoonery of Frank Burns got old quickly, and when they tried to fill out his character to make him a little more human... the audience rebelled. This was the age when Neilsen was GOD, so they were quickly hammered on to make him a sock puppet again. This was in no way the fault of actor Larry Linville... he played the role he was given expertly... and other works show he certainly could have handled a meatier role.

*sigh*

mnem
Ah well... it was all commercial broadcast, which in the end exists to broadcast commercials, and any content that might go along for the ride is purely afterthought...

[tggzzz]

American Idol (and the Gold Rush" production mentality that ensued thereafter) killed Firefly, not the quality of the program material, which was definitely above-average. If it had been allowed to continue, it would've been as highly regarded as Bab5, for the same reason: Its creator had a fully realized vision for the show, with a beginning, a middle and an end.

Even Bab5 suffered from the "money-grubbing executives" disease; the story as written was over after they told all the old ones to fuck off. But the extra season did at least give the primaries a chance to play around a little bit and have some fun with their roles, and as a viewer I appreciated the chance to say good bye to old friends as they rode off into the sunset.

Fortunately that was documented in realtime, with much still available for posterity at http://www.midwinter.com/lurk/countries/us/eplist.html

Or, there is the more complete archive. I remember JMS writing this... (my emphasis)

That's the great irony of the situation. The criteria told to us right
up front while we were producing B5 was that each of the series on PTEN
had to show a profit *in that year* in order to stay on the air and be
renewed. So we'd have these meetings with studio heads who were
congratulating us on how much money the show was making for them
(again, while we were still making for it), and then look at me,
realize what they'd said, and hurriedly add, "Though technically we're
still in the red."

The show, all in, cost about $110 million to make. Each year of its
original run, we know it showed a profit because they TOLD us so. And
in one case, they actually showed us the figures. It's now been on the
air worldwide for ten years. There's been merchandise, syndication,
cable, books, you name it. The DVDs grossed roughly half a BILLION
dollars (and that was just after they put out S5, without all of the S5
sales in).

[25 CPS]

The eevblog video posted yesterday (https://www.youtube.com/watch?v=6TYtdpbFWuA) about fuse characteristics being permanently changed by exposure to low temperature was interesting. He was showing fuses in the context of current shunt overcurrent protection in multimeters.

Dave didn't mention any practical implications, probably due to being in a part of Australia where brutal winters aren't a thing, but there are many locations in the world where fuses routinely get exposed to cold ambient temperatures because not everything is in a climate controlled environment at all times. Anything in an automotive application would be affected and to continue his multimeter example, I always have at least one multimeter in my truck and those would have been exposed to many nights of sub-zero temperatures over each winter. Same with fuse boxes in unheated outbuildings etc.

I'm just puzzling over how big of an issue this actually is in practice and whether it's under-reported given we don't hear much about it or if it's a big deal at all.

[Robert]

OK lets get this back on test equipment.
I bumped into a retired work colleague in a supermarket car park last week and he asked me if I would try to repair an instrument for him. Later that day he turned up with a 1980's Roland Juno 60 synthesizer. That is a musical keyboard not a a RF signal generator
Fault was quickly confirmed as intermittent loss of output. First problem was to get it to fail again.... When it did I was able to select a programe that included noise. This resulted in noise when keys were pressed. This immediately put suspicion on the master oscillator. This is an LC oscillator that runs about 1.9 MHZ and is divided down to produce the notes. It has a Varicap to allow tuning and "bending" Uses 4 bipolar transistors in an unusual circuit. Of course once I oped the keyboard it started working...

master osc cct.jpg

Freezer and hot air failed to stop it but I managed to get a set of dc voltage readings. Thermal imiging gave no clues either. I changed the electrolytics in the MO even though there was no clear fault with any of them. A day later it finally stopped. Now probing around with a DMM would start it up. Mainly around TR61. Voltages were about the same as when it was running. Took it out and it checked ok but at the low end for gain. I fitted a subsitute (BFxxx series I don't have many Japanese series transistors in stock) and it worked for a few minutes and then stopped. Measuring tha DC levels indicated that TR61's emitter current was about 4 times what it was when it was running with the original transistor. Still well within ratings though. Put the original transistor back in and no change. After checking all the resistors I pulled TR60. The trusty Peak Atlas DCA55 said "NPN Bipolar" but the detailed specs said Hfe 4 and high base-emitter resistance. Stuck a BC182L in and it started workng. Further testing showed a a couple of keys were noisy. So I cleaned all the contacts. These do not like "switch cleaner" a wipe with a strip of paper moistened with IPA followed with a polish with a dry strip works well.
A quick check of alignment and back to a very happy owner. He had not realised that this keyboard, that he owned from new, has a bit of a cult following and now change hands for thousands of pounds. It was one of the first (second I think after the Juno 6) synths with a "digitally controlled oscillator.
TE used: Fluke 8060A DMM, Picoscope 2206, Flir E6, Peak Atlas DCA55, and ESR.

Robert.

[Robert]

The eevblog video posted yesterday (https://www.youtube.com/watch?v=6TYtdpbFWuA) about fuse characteristics being permanently changed by exposure to low temperature was interesting. He was showing fuses in the context of current shunt overcurrent protection in multimeters.

Dave didn't mention any practical implications, probably due to being in a part of Australia where brutal winters aren't a thing, but there are many locations in the world where fuses routinely get exposed to cold ambient temperatures because not everything is in a climate controlled environment at all times. Anything in an automotive application would be affected and to continue his multimeter example, I always have at least one multimeter in my truck and those would have been exposed to many nights of sub-zero temperatures over each winter. Same with fuse boxes in unheated outbuildings etc.

I'm just puzzling over how big of an issue this actually is in practice and whether it's under-reported given we don't hear much about it or if it's a big deal at all.

And the date is.....

[tggzzz]

And the date is.....

March 31st
https://www.eevblog.com/forum/blog/eevb ... msg5866735

[Zenith]

The eevblog video posted yesterday (https://www.youtube.com/watch?v=6TYtdpbFWuA) about fuse characteristics being permanently changed by exposure to low temperature was interesting. He was showing fuses in the context of current shunt overcurrent protection in multimeters.

They are crude things with complicated behaviour. There are quick blow, slow blow and weird ultra slow blow versions. Generally they work well enough and blow before real damage is done. I've run an inverter arc welder on 240V UK mains, which I calculated had the 13A fuse in the plug near the 13A limit with the inverter set to 120A, which is a bit hot for most 3.2mm (1/8th") MMA rods run on DC. After I found the fuse would blow unpredictably when using the welder set to 80A for 2.5mm rods.

I always had the impression that the fuses in multimeters were a bit special.

[tggzzz]

The eevblog video posted yesterday (https://www.youtube.com/watch?v=6TYtdpbFWuA) about fuse characteristics being permanently changed by exposure to low temperature was interesting. He was showing fuses in the context of current shunt overcurrent protection in multimeters.

They are crude things with complicated behaviour. There are quick blow, slow blow and weird ultra slow blow versions. Generally they work well enough and blow before real damage is done. I've run an inverter arc welder on 240V UK mains, which I calculated had the 13A fuse in the plug near the 13A limit with the inverter set to 120A, which is a bit hot for most 3.2mm (1/8th") MMA rods run on DC. After I found the fuse would blow unpredictably when using the welder set to 80A for 2.5mm rods.

I always had the impression that the fuses in multimeters were a bit special.

The ones in Fluke 25s and others certainly are: embedded in sand so they can deal with high interrupting currents without buggering the meter internals. You know the kind of thing; connect a 12V lead acid battery to the current terminal, so that part of your probe evaporates.

I also have some exceedingly slow blow fuses. Inside the glass envelope is a short piece of fuse wire connected to a large slab of metal that takes an age to heat up. The short length on the left of this 2A fuse is the bit that evaporates.

IMG_9002.JPG

[Zenith]

I've seen very high value (100A plus) fuses filled with sand (or something). I assumed it was there for quenching. When it blows you want it to stop conducting, not to continue as an arc.

[tggzzz]

I've seen very high value (100A plus) fuses filled with sand (or something). I assumed it was there for quenching. When it blows you want it to stop conducting, not to continue as an arc.

Well, these cigars are 30A, but also "Eaton Bussmann Series Class RK5 fuse, FRS-R, time-delay, dual-element, current limiting fuse, 30 A, non-indicating fuse, interrupting rating of 200 kA at 600 Vac and 20 kA at 300 Vdc"

[Zenith]

One of those things. The principle is simple, a thin conductor that overheats and breaks before anything else overheats and breaks, or causes a fire. The obvious example is the old style domestic fuses, which I believe were a specific diameter of tinned copper wire, which could be replaced. Clearly, a lot of engineering and research has gone into developing them for particular purposes and examining their complexities.

[25 CPS]

I've seen very high value (100A plus) fuses filled with sand (or something). I assumed it was there for quenching. When it blows you want it to stop conducting, not to continue as an arc.

Well, these cigars are 30A, but also "Eaton Bussmann Series Class RK5 fuse, FRS-R, time-delay, dual-element, current limiting fuse, 30 A, non-indicating fuse, interrupting rating of 200 kA at 600 Vac and 20 kA at 300 Vdc"

I found a blown 15A fuse in the heating circuit that didn't work on that streetcar back in February. Whenever it went wrong, wherever it went wrong, someone kept feeding in new fuses and blowing them until the fault causing that to happen burned itself totally open. I don't know if this happened at the museum after the car arrived and was put in service or if it took place at the public transportation system it came from before they retired it. Either is possible and one of my friends works at the same public transportation system and saw one of their HVAC guys blow every spare fuse appropriate for the electric strip heating on their current fleet of streetcars they had in their shop rather than troubleshooting what eventually turned out to be a wad of foil from a cigarette pack that had fallen in through the vent louvres and shorted out one of the heaters inside. If he'd started with a multimeter on ohms, he'd have been a lot further a long with a lot less inventory use. So, having heard that story, I can totally believe the streetcar's dead and damaged heating happening in either location.

The second picture, with my clamp meter in absolutely perfect pre-baboon condition, someone actually did put a 30A fuse in that fuse box and grossly over-fused the motor circuit for the front doors to try and fix a problem where one of the front doors was jamming. The result was the front door that was jamming continued to bind up and jam - but had to be moved manually after the motor burned out since it became the current limiting device after the 30A fuse was substituted for one a fraction the size.

I honestly don't get it. I guess it's hard to find good technicians whether it's a paid or volunteer environment.

[tggzzz]

I guess it's hard to find good technicians whether it's a paid or volunteer environment.

Somebody needs to train them.
If that isn't possible then have supervision.
If that isn't possible (e.g. voluntary organisation) then at least have three people working alongside each other, so that there is a better chance someone will stay "wait a minute". ("alongside" != at other end of cable).

Over here we used to have apprenticeships, where companies trained school leavers before they employed them. That was possible when it was less likely people would be "stolen" by another company and/or move to a different town.

[AVGresponding]

How about, you don't get to touch anything beyond a litter-picker, until you've proved some minimal technical competency?

[tggzzz]

How about, you don't get to touch anything beyond a litter-picker, until you've proved some minimal technical competency?

Nice idea, but who would be willing to take the responsibility for stating someone is competent? Or not incompetent?

Who tests the testers? Who trains the trainers?

With gliding in the UK (unlike elsewhere?), the Civil Aviation Authority has kept oversight but devolved responsibility to the British Gliding Association. That works well because the BGA and its members are extremely competent and very responsible and have many formal and informal mechanisms for ensuring that continues.

Plus there are some heavyweight laws, e.g. glider accidents are investigated by the same people that investigate 747 accidents. In at least one case a glider that underwent rapid unscheduled disassembly in mid air was forensically examined, and the results significantly shaped how airliners are now built from composite materials. Here's a 10min BBC documentary on it:

[Robert]

And the date is.....

March 31st
https://www.eevblog.com/forum/blog/eevb ... msg5866735

Not in OZ. They are first for the new year too...

[Robert]

It was actually a well thought out con. Freezer level temperature does affect the crystaline structure of some alloys. For example in aviation after annealling rivets they work harden at room temperature. This can be slowed by keeping them in a freezer.
The treated fuse that blew quickly was obviously caused by Dave picking up the wrong fuse.

[tautech]

And the date is.....

March 31st
https://www.eevblog.com/forum/blog/eevb ... msg5866735

Not in OZ. They are first for the new year too...

Nope, we Kiwi's beat them to midnight by 2 hours minimum.
Perth in WA is a further 2 hrs behind NZ.

[25 CPS]

It was actually a well thought out con. Freezer level temperature does affect the crystaline structure of some alloys. For example in aviation after annealling rivets they work harden at room temperature. This can be slowed by keeping them in a freezer.
The treated fuse that blew quickly was obviously caused by Dave picking up the wrong fuse.

Freezing temperatures can definitely affect the properties of metals. I live on the great lakes and there have been a number of notable wrecks in cold weather where some older steel formulations would change from being ductile to brittle when sufficiently cold and ships have broken apart from it with lives lost, so yeah, cold treating metals resulting in different properties than those encountered at room temperature is entirely believable.

[MED6753]

It was actually a well thought out con. Freezer level temperature does affect the crystaline structure of some alloys. For example in aviation after annealling rivets they work harden at room temperature. This can be slowed by keeping them in a freezer.
The treated fuse that blew quickly was obviously caused by Dave picking up the wrong fuse.

Freezing temperatures can definitely affect the properties of metals. I live on the great lakes and there have been a number of notable wrecks in cold weather where some older steel formulations would change from being ductile to brittle when sufficiently cold and ships have broken apart from it with lives lost, so yeah, cold treating metals resulting in different properties than those encountered at room temperature is entirely believable.

That's what doomed the Titanic too.