Need a second hand oscilloscope - Page 1
Forum section: electronics / general

author: adharsh96
author_rank: Newbie
timestamp: April 10, 2020, 04:30:45 pm
content: Hello all,Am a 3rd year engineering student and i do electronics hobby project in my home from my 5th grade.I still don't own an oscilloscope and can't afford a new one. They are way heavy for my pocket, and i use the college lab oscilloscope and it sucks while am at home.Does anyone have a spare oscilloscope?Please help.Thankyou.(Budget less than $100 usd)

author: bob91343
author_rank: Super Contributor
timestamp: April 10, 2020, 05:07:51 pm
content: Too far to ship but I have a few 'scopes in the closet, available for not much money here in Los Angeles.

author: jemangedeslolos
author_rank: Frequent Contributor
timestamp: April 11, 2020, 01:01:22 pm
content: A litlle USB scope like the Picoscope 2204 series can be a great solution for youSmall BW but maybe enough for you?

author: tggzzz
author_rank: Super Contributor
timestamp: April 11, 2020, 01:14:24 pm
content: Radical suggestion: don't have an oscilloscope at all. Insteadthinkabout the theory tounderstandandpredict. Use simulators where beneficial.When prediction isn't enough, use your imagination to work out how to useindirectmeans of fulfilling your objectives. Example: when designing and building my first 6800/128byte computer from scratch, my debugging tools were switches, LEDs and a voltmeter. I did everything with those, except for verifying signal integrity.A recent example was debugging an oscilloscope fault where I knew the expected waveforms but could see them with an oscilloscope, because they were sitting on top of a -2.4kV voltage. Instead I used a multimeter across the relevant points, and observed theaveragevoltage to see if it changed as I expected. It did, and I located the fault. (N.B. for the avoidance of doubt, that wasn't safe and I could have stopped my heart if I had slipped)Those concepts and mentality have provedinvaluableduring my career, when test equipment was not available or simply did not exist.That's the reason for my .sig

author: bob91343
author_rank: Super Contributor
timestamp: April 12, 2020, 01:30:39 am
content: Well it's certainly true that having tools won't make you smarter. But they can underscore your knowledge and give confidence.So it's good to have a 'scope so you can prove to yourself what you know, and of course show what you don't know.Simulation has its pitfalls. The main one, as I see it, is keep you from getting the feeling of the hardware. What a resistor looks like, how strong are its leads, how good is the soldering, is anything too close and perhaps shorting, etc.Simulation is intellectual and a good thing, but it can only supplement hands on.I just did a repair that couldn't have been done with test equipment or software. It was part luck and part that strange mental quirk that enables one to troubleshoot. And since I am on my own time, not needing to please an employer, I can take breaks and work on other stuff or get a snack or just leave it on the bench for a while. Those are actually necessary to regain perspective.An engineering degree is nice but it takes a lot more to do good stuff. You can call it experience if you like but it's necessary to make lots of mistakes. When I teach, I tell my students that they are going to make a million mistakes so let's get some of them out of the way now.Anyway I suspect the OP isn't even in the USA so I can't offer one of my spare units.

author: james_s
author_rank: Super Contributor
timestamp: April 12, 2020, 06:43:22 am
content: Yeah simulation is a useful tool but I don't find it very engaging. It's far more interesting to use real tools that I can feel and touch, and see the effects of real world factors directly on the circuit I'm working on.

author: tggzzz
author_rank: Super Contributor
timestamp: April 12, 2020, 07:52:13 am
content: Quote from: bob91343 on April 12, 2020, 01:30:39 amI agree, but would addpractical testing is very different to theoretical designtesting has its pitfalls too, e.g. choice and use of scope probesTheory without practice is mental masturbation.Practice without theory is blind fumbling.Both are necessary, neither is sufficient.

author: Mr. Scram
author_rank: Super Contributor
timestamp: April 12, 2020, 12:36:06 pm
content: Quote from: tggzzz on April 11, 2020, 01:14:24 pmDo you have one now?

author: tggzzz
author_rank: Super Contributor
timestamp: April 12, 2020, 01:24:58 pm
content: Quote from: Mr. Scram on April 12, 2020, 12:36:06 pmI have too many now. As I'm sure you realise, that doesn't change my points.Also see my previous response to bob91343, immediately preceding yours.

author: BravoV
author_rank: Super Contributor
timestamp: April 13, 2020, 03:37:00 am
content: Posted a reply to other similar thread that an Indian begged for free scope, read it ->HEREor just read the whole thread.

author: Pcaiman
author_rank: Contributor
timestamp: April 13, 2020, 07:13:53 pm
content: Quote from: bob91343 on April 10, 2020, 05:07:51 pmhi i can send a pm?