I'm starting to get a bit fed up with having my test equipment blow up just when it's needed. This is the drawback with vintage gear; if it's not used frequently then it can go *bang* the next time you switch it on. It makes for good practice in repairing stuff, but wastes a lot of time which could be better spent doing other things. I think it's time I modernised my test gear. I was just wondering if anyone has any recommendations they can share. Is there a particular piece of test equipment you couldn't live without? Something you're particularly impressed with? I'd be interested to know so I can perhaps acquire said item and thereby reduce the number of explosions I experience.
I have not heard a bad word said about Rigol scopes yet. Siglent do some interesting RF stuff at competetive prices, assuming the quality's good (again, not heard anything to the contrary).
I don't think any of us here truly understand what electrons do, Jan! Boat anchors don't impress anyone nowadays; they're more likely to make one look like some sort of oddball mad scientist who couldn't get laid. ;-) I'm guessing you don't have a TV. Would I be right?
Boat anchors can still be great as they require you to understand better what is being measured and don’t hide things away with abstraction and unhelpful software.
If you only use it on weekends, you'll probably continue to have problems - even if it's only remembering how the equipment is supposed to work.
You'll find that it's connectors, batteries, heaters, indicators, software and personal safety equipment that wear out most frequently. If your test gear includes any of these, maintain them regularly to avoid disappointment.
If you find that you are missing something that you need, address THAT issue.
Jan, you forget that we had the *advantage* of starting from the beginning and having to make or scrounge everything.
When I started, there was nobody with much knowledge of electronics to help me and very little material of any kind. My city had been bombed during WWII (not as bad as Amsterdam, but bad, nevertheless) and both my grandfathers showed us how to make furniture from odd scraps of wood. The family motto seemed to be "If you can't make it, you can't have it".
I eventually learned to solder with a gigantic 65-watt iron that could undo two tags of an octal valveholder while you tried to solder the third. I saved my pocket money for a year to buy a government surplus multimeter - and when it arrived, the pointer was lopsided and the safety cutout had been glued solid. There was no "Sale of Goods Act", I just had to take it apart and mend it myself.
I begged scrap radio and television sets off a local repair shop to use as a source of components - you made what you could with whatever you had to hand. Government surplus valves were available but expensive; you just had to hope they were not too low on emission, because nobody had any way of testing them. Amplifiers were 'designed' by rote: the anode load resistor of a 6J7 was 47k - or 100k - nobody knew why. A 6V6 needed a transformer to match it to the loudspeaker - any transformer, - nobody knew how to calculate ratios and it wouldn't have mattered if they had, because the chances of finding the correct transformer were nil. Data sheets were a closely-guarded secret, I never even saw one until I went to college.
My first oscilloscope was an EMI WM2 (partly designed by Alan Blumlein, I believe). It was absolutely lethal to work on and most of the components were out of specification or intermittent, so It only worked for brief periods between long intervals of failure and repair.
When I took the job of setting up an electronics workshop for an educational establishment, we could afford a 12v soldering iron but no transformer, so I begged a scrap pre-war one off my cousin's business. I set about building a stabilised power supply around it, but it had to be switched off each time I wanted to make a soldered joint, so I had to be quick and finish each connection before the iron cooled down. We had no large resistors, so I loaded the power supply on test with a plastic bowl full of salty water and a couple of pieces of aluminium plate.
Many of the huge 'boat anchors' of test gear, so despised by the modern generation are still working and still perfectly adequate ...as long as you know what you are doing.
I know they have their advantages, but they can also tell lies by showing glitches in waveforms that are internally generated by the scope rather than the DUT. For such occasions, it can be very useful to keep an old analogue scope. I've got 13 of 'em!
Yes, and more importantly, they can be *kept working* indefinitely because although they do blow up quite frequently, they're also pre-SMT, so even people with my shaky hands and poor eyesight can repair them. Thank god for through-hole! Your comment on the soldering iron reminded me of my first one which had to be heated up with a blowlamp. I managed to find one on Ebay for illustration:
Some instruments do kick crap out of their inputs. I have an otherwise very nice Krohn-Hite tunable filter box that is hard to use because of its terrible kickout.
Scopes generally don’t do that, because there are vertical amps and attenuators in the way.
However, you do need to understand a little bit about how sampling works. For instance, say you’re looking at a noisy signal. You want to see some more detail, so you start cranking the horizontal scale knob to the right. Everything looks fine until you get past the maximum sampling rate.
The scale keeps getting finer, but the display breaks up completely, turning into a lot of nearly vertical lines. Of course that’s because it’s gone from real-time to equivalent-time sampling, but it’s puzzling the first time you see it. (To the analog-only folks: ET is useful, but requires careful attention to triggering and averaging. )
In general, 1980-2005ish vintage boat anchors really rock, but you have to get the best. Just yesterday I bought a Tek TDS 684C—1 GHz BW, 4 GS/s simultaneously on all four channels, with fabulous knob response. It was $300, about 1.5 cents on the dollar versus new.
When I was at IBM, bought one brand new in the late 90s (probably $20k) and used it for nearly everything.
I’m a big fan of those too, and use them often. I have a very nearly complete collection of sampling and O/E heads, too—just missing the SD-32
50 GHz sampler.
Right now I’m working on a lab amplifier, based on three paralleled SAV-331+ pHEMTs. Characterizing its noise performance is turning out to be a bit of a puzzle, despite a pile of top-of-the-line boat anchors, but I’ll keep that for its own thread.
Very true about specifically the 1% statement. Sidebar, at an earlier employment, we needed to equip a new lab. Guys wanted GHz scopes. When asked if the ever looked at edges faster than 1ns, no one did.
It’s true that there are a lot of relatively undemanding jobs in electronics. You can get on fine with a 200-MHz scope if all you’re doing is PIC and Pi and ham radio and analog TV.
It’s also true that you can often make do with what you have—the most important test instrument is the one between your ears.
In the before times, doctors were much better with stethoscopes than they are now.
But I’d sure prefer a cardiologist who could use tomography and ultrasound over the best stethoscope guy.
And it’s a lot easier finding gigahertz oscillations if you aren’t limited to a 10-MHz scope with scale marks in cuneiform.
Good boat anchors make capability like that very affordable. My lab is full of top-of-the-line gear (over $2M at list price), for which I’ve paid about
2-3 cents on the dollar. (Not counting a few very helpful donations early on.) Of course I have some good newer stuff, such as a two-channel arb, a NanoVNA2, and a logic analyzer with protocol decoding.
It’s a bit old-school-looking, so it doesn’t impress visitors unless they actually know something, and that suits me perfectly well.
But by all means don’t buy any, so it’ll keep being cheap for me. ;)
Back in the 1970s I found that a BC109 could be used as a self- oscillating transmitter output stage at 100 Mc/s on a 1.5v supply (it was for small animal cardiography). Most "R.F." transistors wouldn't work under those circumstances.
We used to make bugging devices using '109s with button cap microphones that worked on that VHF broadcast band. They were highly effective as I recall.
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.