oscilloscope

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I don't own or have access to an oscilloscope, but I will desperately need one, especially when it comes time to make my big amp. I don't have the money for a new one. There are several ADCs that can be used with a computer and software to form a DSO. Does anyone know of such a thing for less than $300? Maybe even less than $200? By the way, I'm looking for one that can read signals up to almost 200V because I will be dealing with peak signal voltages up to almost 170V. Many such peices of hardware don't go that high. I don't want something with a crappy bandwidth either, and I want at least two channels. I'm sure many of you know what else to look for in a good scope better than I. Another option would be to build my own scope. I have several good CRTs laying around, and I might as well use one. They're all quite big though, and would make for a very cumbersome piece of equipment. Is there anywhere I can find all the information to do this? I have no idea what that would involve. It might be way too hard and/or too expensive.

Any recomendations?
 
My oscilliscope cost less than my multimeter. Ok, it's old, only has 10MHz of bandwidth, and has some drift. But seriously, you should be able to find (or fix) something from Ebay for the price of the ADC/computer solution, and this has the benefit of being a dedicated tool with robust inputs which is unlikely to blow up your computer.

I may be very wrong, but I think you will need to use a shunt to measure voltages up to 200V with any inexpensive equipment, ADC, scope, or otherwise.
 
When looking for a scope, the first thing I did was eliminate anything non-Tektronix. Definitely a biased choice, but I've used Tek equipment for many years, so I'm accustomed to it and quite familiar with their products. I've also found that Tektronix equipment is all very reliable and easy to use. Given my relative lack of experience with other brands, I cannot say the same about any other equipment.

I managed to find my current scope on eBay at an excellent price ($425 for a Tek 2445 4 Channel 150MHz scope in great condition!). So, I think for $300 you can buy an excellent scope. Here are some useful websites to help you get started:

Tek scope prices on eBay (a very handy compilation of eBay stats):
http://www.vaxxine.com/phil/scopes/scope$.htm

This website has useful descriptions of most Tek scopes:
http://www.tucker.com/manufacturer/Tektronix.asp

A nice Tek scope reference page:
http://www.reprise.com/host/tektronix/home/default.asp

A very popular and inexpensive scope is the 465. While a little older than other models, it still has 100MHz bandwidth, dual trace, and it has probably one of the sharpest traces of any scope Tek ever made.

Anyway, good luck with it. :)
 
I just got a hp 1715a 200mhz scope off ebay for $73, so there is hope of getting a good used scope for cheap. It should be even easier for you since you don't really need the high freqency. I originally lhought about a ADC, but after looking at ebay I decided to get a real scope. It took a few weeks of watching ebay until I found what I wanted in my price range. There are divide by 100 probes that will make 1.7v out of you 170v.
 
Hi all,
Talk about the forum answering questions before being asked, I was about to start a new thread on scopes as I have been offered a Tektronic 5111 storage scope, 5A22n Diff amp, and 5B10N Time base amp.
I have no idea how good it is, or if its good enough for basic audio work. Can anyone help on suitability or advise if I should buy it.
Just for laughs, it has been offered to me for South African Rand, R400.00, about 35 odd American Dollars. For once it seems that our very weak currency is working my way!

Dieterd
 
Hello kilowatt,







Originally posted by Kilowatt



I don't own or have access to an oscilloscope, but I will desperately need one, especially when it comes time to make my big amp. I don't have the money for a new one. There are several ADCs that can be used with a computer and software to form a DSO.








if you are new to oscilloscopes, you should stay away from DSO for a start. Yeah, I know, I sound grandpa-like, but a DSO is just the right thing to observe waveforms you already know the shape of.



But if you do not know the waveform's shape, you do not know whether the DSO shows you the reality or an artifact i.e. a waveform not having much to do with the signal. Such signals could be HF-oscillations or glitches ot oscillator jitter or random signals or causal/single events.







For causal events a DSO seems to be the right thing, but as the event is singular, not repeated, who knows its real shape? The DSO is perfect in telling you such a signal has taken place.



I have an HP 1741A analog storage scope and a Fluke 123 scope meter. For most occasions I prefer the enormously convenenient scopemeter/DSO. But artifacts on tricky signals are usual.



I compared my HP 1741A (which has a single shot option among its storage options) to the LeCroy at the company on a single event spike signal with disturbed rising and falling slope. They looked different on the analog and digital scope. So I know.







Modern super-expensive DSOs like Tek and LeCroy and HP/Agilent have advanced circuitry for avoid artifacts or make them less probable to happen. However I would not count on that cheapo soundblaster-based software-DSOs or lil'boxes containing ADCs and connected to the parallel port have such. And they are not chaep for what they are delivering.




If I would be you, I would buy an ordinary analog scope with atleast 20MHz, better 100MHz of bandwidth. Provided you can trigger the signal, the analog scope tells you the truth. Add a DSO later when you have become acquainted with scopes and never give away your analog scope.






Does anyone know of such a thing for less than $300? Maybe even less than $200? By the way, I'm looking for one that can read signals up to almost 200V because I will be dealing with peak signal voltages up to almost 170V. Many such peices of hardware don't go that high. I don't want something with a crappy bandwidth either, and I want at least two channels. I'm sure many of you know what else to look for in a good scope better than I.








Look for used Tektronics or HP scopes. Tek 465 ,466, 468 is a good choice.
Why not ebay or your local surplus store? My HP comes from our surplus store.
Before I forget it: buy probes with atleast 3 times the bandwidth of your scope.







Another option would be to build my own scope.








Do you want to build scopes or amplifiers?



Do you want to hone your tools or get progress in your projects? ;)



Bernhard, you hear me?? :)







Greets,
 
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