I thought as the weather is so very bad here in the Northeast of England right now, I’d spend some time reviewing equipment – so I’ve a load of stuff coming in the next few weeks – first off is the Owon SDS1102 oscilloscope.
Before I start, you need to be aware of where I’m coming from. I’ve been using a World War 2 scope since the late 1980s. That’s a slight exaggeration, the SS3510 50Mhz scope has kept me in good stead for many years – a dual beam scope able to handle many of my day-to-day tasks. It has two problems which I’m no longer able to put up with… 1) weight – it is heavy and I do a fair amount of lugging back and forth. I could not even conceive of selling it on Ebay as the postal charges would likely exceed the selling price… and 2) size. It takes up a significant part of my bench space.
So – the SDS1102 is a mains-powered desktop scope and is as light as a feather. Now, before you starting thinking “cheap” – actually despite the lack of weight, no, it doesn’t feel or look cheap and I hope that shows through in the video. The scope is one of a range of scopes, there is a lower-cost 20Mhz version called the SDS1022 as well.
Some time ago I looked at a desktop LCD scope and compared to my shiny green analog scope the display was washed out, particularly at an angle and the whole thing seemed a little “slow”. Well, I’m here to tell you that this new scope is neither of those.
The display, despite being only 800px wide is excellent at ALL angles and as for speed, clearly, the first thing I did when plugging the scope lead in was to give it the finger test… the response was instantaneous – by which point I was beginning to realise my scope experience was out of date. After I did the finger test and froze the image, I gave the “measure” button a go and after selecting channel 1 was greeted with a screen-ful of information including period, mean, rms, minimum, base, overshoot, duty cycle and much more – just an amazing amount of information on the signal.
The funny thing is, when I last looked at my old scope, after giving it the annual clean up, I was thinking how it still kind of looks right on the bench. After a day of playing with the new scope I can hardly remember how I could possibly feel that way – the old tube-based SS5310 is going in the bin when it stops raining. Time to move on.
This particular own scope is described as being a basic model and yet is a 100Mhz, 1GS/s dual beam job with PC interface. Aside from the power plug, absolutely everything is on the front panel so if you’re tight for space, it can squeeze in without having to worry about getting around the back for anything.
The scale goes from 2ns per division to an amazing 1000 seconds per division – yup – 1000 seconds. Looking forward to using the latter for battery testing, something I'd never thought of until I started watching Robert Murray Smith videos...
Obviously it comes with two scope leads (I say obviously but my recently acquired BitScope came without any), power cable and manual – the manual being in full English. There is a full manual on the web but in true experimenter fashion I’m leaving that as a last resort.
I would say in all honesty, in order to do anything useful with the scope I had to play with it for maybe half an hour, by which point I felt entirely comfortable. The unit has it’s own calibration software as well as the usual 1Khz test connector.
Much has been said about digital scopes and their display of noise. Anyone with an old analog scope, coming to these will notice the noise on the waveform, well, part of that is due to the old analog scopes averaging the signal over time and hence somewhat disguising said noise. If you want to pretend you have an older scope, you can usually apply limit filters and the Owon is no exception, there is a 20Mhz filter option on those buttons down the right hand side of the screen.
It is also fair to say, for someone not familiar with scopes at all, that you would not want to be trusting the waveform display at anywhere near the stated maximum (100Mhz) - for more on that, check in once my signal generator turns up - but for general work, for example checking signals on small IOT microprocessors etc., this unit should be more than sufficient and unlike my older scope, the input levels appear to be quite accurate. Given a meter reading of 3.76v, the scope showed 3.8v.
In a matter of days I should have my new function generator from Banggood so I’ll be able to update this blog with more useful info – I’m sure you don’t want to see endless photos of a square wave.
In the video are some technical specs… and of course all of that is available on the OWON website.
Since writing the original review I've discovered that the USB connector on the front is for storing images and on the right side is another USB connector for connecting to a PC.
The 1.32 version software that comes on the SD appears to be fine – at first I could not get it to work but then I looked in device manager and realised that (unlike many UART products) this was not going to work without the driver (Windows 10, 64 bit) – I installed that and loaded the scope software and everything worked fine. On the website there is version 2 software and for some strange reason, version 1.2 – neither of them are any good so the software that comes with the CD seems to be the best.
The software however does not form a live scope for the PC – as best I could tell you can capture readings. Changing the volts/div on screen and the scale affects only the scene you have recorded… not the scope itself. So this might be useful for examining some data – but that’s about it.
Update December 2017: Having had this scope on my desk for a while now it is certainly invaluable. The twin view (HOR) allowing you to see the entire captured wave and zoom in on part of it is good and also the ability to slow right down to 1000 seconds per division is useful for monitoring supplies etc..
Another really neat feature I just discovered is somewhat like the old phosphor memory – which you can turn on and off… older traces remain on screen momentarily, fading out over a programmable number of seconds. This is called PERSIST and it just one of many, many features as you wade through the menus.