A little over 17 years ago, I realised that if I wanted to continue designing electronics equipment, I needed to upgrade from my flaky old analog scope to a digital storage scope or ‘DSO’.
So I took a deep breath and invested in a shiny new 100MHz 2-channel DSO from Tektronix (the TDS320).
It cost around $4500 if I recall, which seemed like a massive sum; but it also seemed to offer pretty well all the features I’d need for some time to come.
And this indeed proved to be the case, as the trusty TDS320 served me faultlessly until a few weeks ago.
But then its traces flew out of sight, off the top of the screen and couldn’t be persuaded to come back. The front panel board had developed a fault and I found that replacement boards were no longer available.
These two shots give a good idea of the width and depth (or more accurately, the lack thereof!) of the DST1102B. The rear panel is pretty spartan, with just the power input and that second USB port.
My only options were to send the scope back to Tek in the USA together with a cheque for US$1550 to cover a ‘best efforts only’ repair, or to use the TDS320 carcase as a trade-in on a new DSO.
Since sending the 7kg TDS320 back to Beaverton in Oregon would probably cost about $400-500 anyway, with no guarantee that they would fix it, the decision was easy – it was clearly time to upgrade to a new DSO.
So I began searching the web, to see what might now be available in my price range. And straight away I started to
realise just how far DSOs had come since I had invested in the now-ancient TDS320.
Just about all of the latest models offered full colour LCD displays, for example, instead of the hefty 7” monochrome CRT monitor I had become used to.
This made them dramatically smaller and lighter in weight, while at the same time making the display much clearer and easier to analyse.
There had also been a significant increase in sampling rates and an even more dramatic increase in sample memory depth. Many of the latest models offered real-time sampling up to 1GS/s with a memory depth of well over 10KS (kilosamples) and in some cases up to 500KS or 1MS – a big advance on the 500MS/s sampling rate and modest 1KS memory depth per channel offered by my old DSO.
Most of the new models also offered a wider range of automatic measurement functions, including FFT frequency analysis, plus a more comprehensive range of triggering options. Just about all of them also offered the ability to save waveform screens and setups in either internal memory or a plug-in USB flash drive – or both.
Yet at the same time, the price tags on all of these latest models had dropped dramatically from the $4500 I had paid for the old TDS320. Some of the 2-channel 100MHz models were down to below $1000, in fact.
So I was faced with picking my way through a bewildering array of models offering all kinds of fancy bells and whistles, with prices ranging between about $1000 and $2500. If you’ve been looking for a new DSO you’ll know exactly what I mean.
Now I’ll cut to the chase by telling you that after quite a bit of downloading and comparing specs, I finally settled on the new DST1102B scope made by Tekway Technologies in its factory in Hangzhou, China.