Test Equipment Anonymous

Back to our raison d'être... I've recently tested a PSU set to 40mA 30V, with a 47ohm resistor so it should limit at ~2V. It output 30V for >100ms, then exponentially fell and undershot, and after a second got to the correct value! Here are some results for PSUs available to me. The good: AIM-TTI P...

I didn't mind a few inches of snow when I was working, as long as it didn't hang around long enough to wear its welcome out.

I'll (reluctantly) agree with the above. Mind you, I looked after my kit at work exactly as I do at home; Then some of it will have been through the military, or worse, the education sector - technical colleges and universities. Sometimes the handles weren't all that robust anyway. All considered I...

Yes but in professional and industrial settings equipment isn't deliberately knocked about, but neither are people meticulous in looking after it. So handles can be broken and bits and pieces lost.

It depends on the equipment. Sometimes it has a case and the handle is not accommodated in the case and so was never there or was discarded. Sometimes the handle is completely broken, or locks unreliably and so is a nuisance. For most people the handle is a nice thing to have, but if it isn't there ...

I have various Metcal tips, but not a knife. I've never investigated knives, so I don't know their advantages. For desoldering, my presumption is that they won't be long enough to touch all the contacts on one side of an IC, and hence less than perfectly sufficient. For soldering, one-at-a-time or ...

A friend's cat. This is an evil bastard. It spent the entire evening nudging people off furniture that it clearly considered itself the owner of. Very cleverly it'd snuggle up behind them and then ratchet its way across the furniture slowly pressuring them into falling off :lol: IMG_2863_.jpeg You ...

It rather depends on the job and how much you would like it to be turned into a routine action, involving no surprises. Something you can just do and be paid for. For instance, fitting a kitchen. The first time you do it, there's all sorts of head scratching about how to go about it and there's ultr...

Thanks for that. I've done a bit of SMD work but I have a couple of serious SMD projects in the queue. I'm sure this will be very useful.

Anyway, they usually come in a fairly light proof enclosure which makes them easier to use, stops them being damaged, and would contain the mess if they were. Unsaturated - as used inside DVMs etc - yes. Saturated standalone references aren't sealed to any reliable degree. With this Cambridge Instr...

I'm fascinated to hear that Weston cells should be kept in the dark. My Tinsley cell is in a nice wooden box and is probably fairly dark inside. You'd be amazed how difficult it is to make something light-tight. Only metals stop light; it's all about Compton scattering and free electrons interactin...

Life was a lot tougher for 1920s modellers. Their lathe was highly unlikely to be electrically powered. Probably treadle. On the other hand, the materials they machined were pretty soft (which is why classic cars and motorcycles wear so quickly). But if you really want to see feats of improvisation...

You'll end up scratch building locomotives and rolling stock from the original blueprints. I've seen it happen. And that means you need a machine shop. Very useful, but expensive. Not so much these days. I came across someone building a 5½" gauge locomotive in his garage. A lot of the difficul...

What is it? An ATU - Antenna Tuning Unit.

Stay away from model railways. It's a slippery slope. You'll end up scratch building locomotives and rolling stock from the original blueprints. I've seen it happen.

There are 1 metre and 1.5 metre SDS bits. They are not particularly expensive. Aldi sell sets of three 1 metre SDS bits for £10 sometimes. They'll go through 30" of limestone wall in three or four minutes.

There are so many sketchy channels these days. I open them in a new window, and look at comments to see if anyone has immediately called them out; if not watch for a while to see how sketchy it actually is. More often than not, I find myself downvoting it, then going back to the original window and...

I have "Most Secret War" as well and don't recall him mentioning the device the video was about. What I do remember was RV Jones telling the reader just how clever he was. It must have been true, otherwise he wouldn't have kept saying so. In that case is it likely that the creator of a wo...

When I was a kid, I wondered why old people were so grumpy; now I know. If you don't become grumpy as you get older, you haven't been paying attention. The video conforms to a type which has come about recently, probably with a lot of AI involved, with misspelled subtitles and the scratchy, dusty e...

Stairs are there to be used by all and the footing should be intuitive, not like rock climbing.

It's a deathtrap.

I've seen those mains frequency meters at hamfests I didn't even pick them up :) Boxes of meters at rallies are worth a quick look over when the first pass has been done. There might be a gem, such as an HP meter of some sort, or a special for an Eddystone, Racal RA17, or Collins. There almost cert...

Yeah, I'd like one of those. But I don't want to have to clean a ham's frequency counter ;) I suppose might be interested in one of the analogue voltmeters as used as digital displays. Presumably they were used with glug-counting decade counters. I can't recall seeing one. Franlab is into weird and...

It occurs to me that a number of my teachers had probably been shot at during WWII, so sodium or calcium in water or spilled mercury were pretty small beer. I remember being impressed by physics master's demonstration of Crooke's tube where he was forcing the bungs in at each end to maintain a good...

Many years ago, there was a pick-up arm made by KMAL (Keith Monks Audio Limited). At the time, low effective mass and ultra low friction were the way to go, so unipivots were popular (especially as you can make a unipivot arm quite easily if you have a lathe). But you needed really fine wire to avo...

And then we get to exposed mercury in the home... ... and during school chemistry lessons, and in dental fillings, and a surprsing range of seafood https://www.nhs.uk/live-well/eat-well/food-types/fish-and-shellfish-nutrition/ Mercury was a mainstay of school labs. I remember an experiment which de...

I've seen a few of them around since but have never been tempted because I have no use, they are bulky, and they are usually tatty. AFAIK they didn't have a torsion wire, it was a thread of quartz. The method of making it was interesting and involved a crossbow. There was a bolt with a bar of quart...