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Today at school I borrowed an oscilloscope and a few capacitors and used a circuit I made at home to just demonstrate the discharge of a capacitor, since my physics teacher asked me to teach the class about this on Friday
So it's one of those old analogue scopes, so to get a nice line I turned the speed right down and did a long exposure shot with my phone and it turned out brilliantly!

Comments
  • 10
    Insta fav.

    @GyroGearloose
    @Condor CONDOR Ya have to see that!
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  • 18
    Face reveal!
  • 5
    I always wanted one of those old boys... Especialy with a ton of buttons and knobs!

    I like my 1054z but good analog one is just the best toy ever :D
  • 7
    I love how the other person puts his hands like that to prevent distractional light to be catched by the camera sensor
  • 15
    Like the reflection... took me 3 seconds to realize it wasn't a girl :D :D :D :D :D
  • 3
    @-ANGRY-CLIENT- yeah we had 3 people involved! One to control the circuit, two for the photo
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  • 9
    @j4cobgarby sounds like a solid base for a joke:

    How many people are needed to capture the discharge process of a cap?
  • 11
    This looks amazing!! Me want scope 😍
    @7400 @Fast-Nop check this out 😁😁
  • 6
    That's exactly why analog, even non-storage scopes often had a single sweep option, despite it not being very useful when viewing it by eye. You'd attach an oscilloscope camera (like this one: https://amplifier.cd/Test_Equipment...) to it and get going. The camera's shutter would be directly controlled by the scope for your convenience, of course.
  • 2
    @7400 wow! I did not know that
  • 4
    @Condor: Thanks for the tag! Go and buy an old analog scope! It's cheap and beats not having any scope anytime. And as @Gregozor2121 said, no DSO can beat the feel of a good analog scope.
  • 1
    @7400 what makes an analog osci. so special?
  • 2
    Accidental face reveal?
  • 1
    @-ANGRY-CLIENT- CRTs are awesome
  • 1
    @7400 that's actually a great idea, now that my current oscilloscope lost some functionality after me trying to flash another firmware onto it. Any particular models you'd recommend? I guess that I'd be looking at a budget of about €100-150 but of course if there's significantly more bang for the buck elsewhere in the range, I'll also consider it 🙂
  • 1
    @Condor I'd love a suggestion too, I'm looking to buy one
  • 3
    @-ANGRY-CLIENT-: Compare it to using Eclipse with a rubber dome keyboard vs. (default configuration) vim with a Model M.

    Firstly, no rotary encoder and rubber pushbutton can have the feel of real rotary switches, pots and mechanical pushbuttons. You know instantly what you're doing based on the sound and the force feedback, without needing to look at anything.

    Secondly, with an analog scope what you do has an instant effect. For a DSO, there always is an ever so slight lag. You're using software after all, which is of course much more powerful, but at the baseline it is simulating an analog experience.
  • 2
    @Condor, @j4cobgarby: Best take some time and look around eBay every now and then. Compare specs and sprices, but also dimensions, weight and availability of documentation and replacement parts. For most scopes full service manuals with schematics and everything are available online, but not for all of them. Some contain hard to obtain parts like ASICs, tunnel diodes or nuvistors that might be an issue if you need to repair your scope.

    Speaking of which, repairing a scope generally needs another scope. Buying scopes thus gets a lot easier after the first one as there are a lot of semi-defect scopes cheaply available.

    I'd recommend to steer around analog storage oscilloscopes. They tend to be fiddly to set up and you can be really unlucky in terms of burnt-out CRTs (they wear a lot faster with wrong usage than non-storage CRTs). I don't have any experience with early DSOs, so I won't go into those. There are combi scopes (e. g. Hameg HM205), though, which might be interesting.
  • 1
    Let's start with 80s scopes!

    The classic first scope is a Hameg HM203 with a bandwith of 20 MHz. It's rather compact, has a sharp trace and is excellently serviceable, because nearly all parts are pretty standard. You see them quite often, but prices vary from 30€ to over 100 as it is a well-known model. There are similar scopes in similar form factors from other manufacturers like Hitachi and Philips (more on Philips scopes later) but I've never seen the insides of one of these. Then again, I dom't think you can get much wrong in this range. Hameg did make higher-bandwidth scopes, but these seem to be pretty rare.

    Tektronix had scopes in the same form factor (2000 series), too. These are generally high quality and feature-filled and naturally rather high-priced. There will be ASICs inside. I lack experience with Tek scopes, so I can't recommend particular models.

    Sometimes you see similar scopes by R&S, which I think are just relabeled Tek scopes (but I never actually checked).
  • 2
    Philips made good quality scopes, too. Their main drawback is that their early switching power supplies tend to screech during operation. A good heuristic for Philips scopes I found for skimming through eBay and Craislist-like sites quickly: If it has the horizontal knob centered above the two vertical knobs, it is a simpler scope with a bandwith around 25 MHz. The better ones tend to have the knobs in one line.

    Older scopes might give you more bang for the buck (especially 4 channel versions), but you're paying for that with desk space and weight, as these things can get huge.

    Tek 5000/7000 series equipment seems to be still quite sought-after and consequently expensive, though.

    You see HP 180 series scopes and plugins quite often and they're not too bad, either.
  • 0
    @7400 thanks a lot for these explanations!!! I'll certainly use this information in my search for a new scope. Turns out that someone here in Belgium is actually selling this Hameg hm203-7 with the highest bid currently at €60. Who knew?
  • 1
    Time to subscribe to this thread
  • 0
    These are the worst take they take time and patience to calibrate. CRT in them sometimes malfunction. And don't get me started on the measurements
  • 1
    Long exposure... That explains why your reflection has four hands. I was wondering about that.
  • 0
    @Gophyr only two two of the hands were mine, in fact
  • 0
    Ok... Btw.... What is the oscilloscope used for?
  • 1
    @GyroGearloose to measure the voltage across a capacitor as it discharges
  • 1
    good shot
  • 0
    hahahaha
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