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Christopher:
Multi: Already got an Extech ex330, going to be getting another £50 china one (UT71E or something) soon.

Scope: Either RIGOL DS1052E (£250) with an upgrade to 100MHz, or the OWON 25MHz PDS5022S (£180) 25MHz but it looks easier to use and has a massive screen. Which would you suggest? I think 25Mhz should be more than enough, and I don't really want a CRT scope.

Also function gens etc, I would like a basic one but don't want to spend LOADS, and I struggle to see how it can be used, I could probably make up a basic one?

amspire:
Definitely not the PDS5022S. It only has 100mbit/sec sampling which means it is more of a 10MHz oscilloscope then a 25MHz oscilloscope.

Also it only has a memory of 5000 samples instead of 1,000,000 in the Rigol long memory. A big memory means you can capture a waveform and then zoom in looking for a problem. The Rigol is a basic screen, but it is good enough, and the 10x faster sampling speed and 200x more sample memory more then offsets the extra cost.

Richard.

rf-loop:

--- Quote from: amspire on April 12, 2012, 08:19:20 am ---Definitely not the PDS5022S. It only has 100mbit/sec sampling which means it is more of a 10MHz oscilloscope then a 25MHz oscilloscope.

Also it only has a memory of 5000 samples instead of 1,000,000 in the Rigol long memory. A big memory means you can capture a waveform and then zoom in looking for a problem. The Rigol is a basic screen, but it is good enough, and the 10x faster sampling speed and 200x more sample memory more then offsets the extra cost.

Richard.

--- End quote ---

If we look what Tektronix or Agilent talk 100MSa/s is well enough for 20-25MHz or even more. Oscilloscopes frequency range mean always sinewave bandwidth. And of course, all what ever waveforms are just sinewaves. There is not any other. If you look square or what ever, it is just couple of sinewaves. If oscilloscope BW is 25MHz it do not attenuate more than 3dB this frequency component in waveform under test. 
Hewlett Packard 100MHz oscilloscope HP54600B have 20MSa/s samplerate.
Samplerate do NOT reduce Owon PDS5022 to under 25MHz oscilloscope. If someone think so it is better to learn more. Whole this samplerate and frequancy BW have so big hassle in allwhere in talking and lot of misunderstanding.

I can tell it can not well 1kHz square wave if want look 1ns risetime edges. So can I now tell that it is not even 1kHz oscilloscope. No it is still 25MHz oscilloscope becouse this 25MHz means sine.

If I take Tektronix analog 2465B 400MHz oscilloscope. It is just 400MHz sinevawe oskilloscoe and not just any more.

It can capture signals what have up to 25MHz frequency components and even more becouse it do not have brick wall BW shape. 

Of course if look example square wave. 25MHz square wave looks very distorted sinewave. Of course becouse scope can show only mother frequency but not any harmonics what it need also show. If there is 25MHz square with around 2ns risetimes it need roughly 200MHz scope to show it even nearly right. And this need analog BW 200MHz and it need absolute minimum 400MSa/s. If analog BW or samplerate is not enough it show square but ristetimes are wrong.

In Rigol if it is modified to 100MHz it have around 3-3.5ns risetime and what ever is samplerate it do not show more details. 

Owon PDS5022x have 14ns risetime and samplerate is not any limiting factor for this 25MHz frequency band.

But example old HP 54600B 100MHz oscilloscope... it have enough analog bandwidth BUT samplerate is limiting factor and it drops this 100MHz repetitive oscilloscope to maximum 4-5MHz single shot oscilloscope. (4-5MHz real time)
This Owon is still 25MHz real time scope.
There is not any need sample more than 3 - 5 sample per cycle as long time if we use good sin x/x and as long as we talk sinewave response. And all oscilloscopes what I know with nearly 40years experience have specified sine BW.

There are lot of basic oscilloscope fundamentals availabe just after some keyword and mouse click so I do not link these here.




About this Owon.

It have one poor thing. It is old! PDS5022S have old piece of crap DSTN display!

Becouse this DSTN display, think twice before buy.
Owon have made PDS5022T  and it have real good 8" TFT.
If you have posible to first look and try somewhere with own eyes this PDS5022S (dstn) model and if  you still can accept this display ... well ... it ok entry level oscilloscope if frequency is not limiting.
(but becouse this is DSTN display and manufacturer have done time ago same model with TFT,  I think you can ask markable amount discount!)

btw, it have not channel shared memory, both channels have individual 5k (in TFT model)
I do not know how this scope sampling is arranged, do they have simultaneus sampling or do they have interleaving? (my quess is it have 2 x 100MSa/s simultaneous - just quess and I hope someone tell who know it.)

But ower the world this Canadian - Chinese  oscilloscope l is lot of used, specially in many many  schools.

T4P:
Didn't dave talk about the nyquist-shannon sampling theory before ?
A 100MSa scope is basically a 10MHz GENERAL wave scope . Nothing more .
Those low MSa scopes of the past are the past they were low back when digital scopes weren't good at all .

Christopher:
I'm only a beginner, not going to be doing any highspeed stuff (Just pissing about mainly), so I need a cheap scope that's worth the money.

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