New used scope or old used scope? - Page 1
Forum section: electronics / testgear

author: knotlogic
author_rank: Regular Contributor
timestamp: August 20, 2015, 06:39:48 am
content: I'm looking at getting a "new" scope, and have generally narrowed it down to either getting an Agilent X2000 or an older DSO5000/6000. My budget means I'm looking at a used unit, and therefore also much less likely a 6000 series. I'm having a hard time deciding though which way to go as both have their pros and cons.From what I've seen:X2000The good:Readily availableScreen size 8.5"MSO option5 year warrantyThe less good:2 GSa/s Half-channel or 1 GSa/s100 kpts memory, 1 Mpts optionalScreen resolution 800x480GPIB, LAN/VGA are optional modulesThe other:200 MHz bandwidth>50,000 waveforms/s(?)Calibration availableDSO5000The good:8 Mpts memory4 GSa/s on 500 MHz at half-channel, else 2 GSa/sScreen resolution 1024x768GPIB, LAN/VGA includedAvailable up to 500 MHz bandwidthThe less good:Screen size 6.3"No (or as good as no) warrantyNo MSO option (Any possibility of triggering external LA?)The other:Up to(?) 100,000 waveforms/s(No) Calibration possible for a discontinued product?Hackable?This would be a personal unit, and I mostly dabble with microcontrollers. AVR for now, but I'm looking at getting into ARM-M which brings with it higher clocks.So I thought I would ask what people think of these two scope lines. Ideally I'd like to hear from people who have used one or both of these since there's no substitute for hands on experience. I've used a Tek and Agilent before at work and just couldn't get used to the Tek.Also, it is possible to get a DSO5000 scope calibrated? Or repaired if need be?Thanks!

author: Berni
author_rank: Super Contributor
timestamp: August 20, 2015, 07:21:08 am
content: I had my MSO6034A for some time now and it makes a great scope. If you want speed this scope will give it to you. It boots up in 10 seconds and pretty much every knob and button reacts instantly (Including the vertical trace offset knob, digital scopes often struggle with that).Personally i never found the MSO part of it all that useful, almost everything these days is serial so you never need more than 4 channels. The SPI decoder is pretty smart too in that it can guess the CS line by looking at the clock timing, so you only need 2 channels to look at one direction of a SPI bus.Screen size is not an issue if you have the scope close to you on the bench, the extra resolution on it is very welcome since it shows a very crisp image of your waveform and the 8M of memory is a pretty useful thing to have when looking at large blobs of serial data. And if you care about it you get things like VGA and LAN as standard. Also you get the smart probe interface on it if you ever buy active probes for it.Things i don't like about it is that the trigger menu buttons could be arranged better, no push to zero on the horizontal offset knob and the scope being quite power hungry, kicking out a ton of heat out the back.Also if you are doing digital its bandwidth thats the most important part. To look at a digital square wave signal you need at least 5 times more bandwidth than its frequency. otherwise it just turns in to a sine wave. If you want to have a good look at overshoot and ringing on it then its more like 10x bandwidth. This means if you want to work on 100MHz digital stuff you want to get a 500MHz scope.

author: tautech
author_rank: Super Contributor
timestamp: August 20, 2015, 08:25:03 am
content: The one with more memory, in time you will know why.

author: knotlogic
author_rank: Regular Contributor
timestamp: August 20, 2015, 02:46:58 pm
content: Quote from: Berni on August 20, 2015, 07:21:08 amYes, I actually was hoping to find a used 500 MHz scope for that reason. Which is a shortcoming of the X2000 series in my case.Is there much difference between the 5000 and 6000 series?Quote from: tautech on August 20, 2015, 08:25:03 amAnd yeah, more memory is also nice to have. But it's really going to boil down to a tradeoff of overall features, and what I can find/afford.

author: Berni
author_rank: Super Contributor
timestamp: August 20, 2015, 04:18:27 pm
content: I never seen a 5000 "in the wild" but it looks like its simply a more compact version of the 6000 .The thing is pretty much as deep as a regular CRT scope so better have a deep equipment shelf on your workbench .But it does have a useful large storage compartment under a lid on the top of it that easily stores all your probes and extra stuff (I don't use it due to stuff being on top of my scope of it but someone else might like it). Also as far as i know the 7000 is identical too, just has more of the X2000 form factor to it (I wanted one of those but they cost too much back then)It can be a pretty hard decision, i was interested in the new X series scopes back when they came out but they just got too expensive at good bandwidths.As far as memory goes you are going to be pretty disappointed with 100k of memory when doing digital stuff. 1M is okay in most cases but i found the 8M on mine pretty useful.If you work with digital a lot you might want to get one of these PC based logic analyzers. I have an original 8bit saleae logic and a chinese knockoff 16bit one. They are not super high speed at only 100MHz or so but will do for a lot of cases and because they stream the data to your PCs RAM you basically got infinite sample memory. I find it easier to browse trough the serial decoded data on the PC using a mouse and the knockoffs are dirt cheep. No replacement for a scope but its a nice compliment to one and much cheaper than a MSO option.