12-07-2020, 09:55 PM
Mike, much as I steered Rob away from a DSO for his needs, I really hope my responses were more balanced and better informed than yours. Your post suggests you made up your mind based on 1980s DSOs and haven't re-considered your position since. For a text-only medium like a forum, it might be a good idea to "soften" your choice of adjectives, if you'll forgive me for saying so.
The Rigol DS1054Z is a "cheap" digital 'scope. Despite that, the sample rate is 1GHz. The input attenuation is far from "useless", and there's no way the trigger performance could be described as "poor".
The 1054Z does a really quite good X-Y mode - you certainly can't say that it "doesn't work". As well as full screen, it does a split dual display, with the two inputs on shown on a conventional scope-style display and the X-Y display beneath. Being able to see both at the same time is really very nice. However, Lissajous figures are one of those curious things that text book authors and sci-fi set designers love, but are hardly seen in the real world. But as a display for a wobulator, the Rigol would do an excellent job, with none of the flicker you'd get on an analogue screen at slower sweep rates (though my DM63 has storage, so variable persistence mode gets around that).
Yes, high sample rates are required for real-time sampling of non-repetitive waveforms, but for repetitive waveforms - which, by definition, is what you'd look at on an analogue 'scope most of the time - equivalent time sampling means that the sample rates don't have to be anything like as high as 10 times the input frequency. I have an old Philips/Fluke "Combiscope" which, because of its age, uses equivalent time sampling, and actually, it's pretty good - there's no way it can be accused of "rubbish accuracy". Being a combiscope, you can switch between analogue and DSO mode with the press of a button, so if there is any doubt about the integrity of the display in DSO mode, an instant reality check is available. It's a nice 100MHz 'scope - I would use it as my default 'scope if it wasn't for the really noisy fan (worse than the Rigol once it's been on a while).
You mention cars, but didn't specify what sort - given that cars can cost anything between free and several million, we'll have to "park" (groan!) that...
Having said all that, for the sake of balance, we do have an Owon at work - can't remember the model number, but it's quite old now. Now that really is a very bad example of the breed - as I said to my colleague before he bought it, it was in the CPC clearance section for reason! There's lots of damning things I could say about it, but it wouldn't be fair or right to do so without reporting the model number and including specific facts supported by photos and perhaps a few links to videos and reviews that back up what I'd say.
I have no problem with criticism if it's measured and supportable. Sweeping (sorry - bad pun!) generalisations, however, are much less welcome. Sorry to moan - I try to let it go most of the time, but if I don't pipe up now and again, it begins to look like that style of posting - which can be rather off-putting, especially to newcomers - is tacitly accepted or even encouraged here.
The Rigol DS1054Z is a "cheap" digital 'scope. Despite that, the sample rate is 1GHz. The input attenuation is far from "useless", and there's no way the trigger performance could be described as "poor".
The 1054Z does a really quite good X-Y mode - you certainly can't say that it "doesn't work". As well as full screen, it does a split dual display, with the two inputs on shown on a conventional scope-style display and the X-Y display beneath. Being able to see both at the same time is really very nice. However, Lissajous figures are one of those curious things that text book authors and sci-fi set designers love, but are hardly seen in the real world. But as a display for a wobulator, the Rigol would do an excellent job, with none of the flicker you'd get on an analogue screen at slower sweep rates (though my DM63 has storage, so variable persistence mode gets around that).
Yes, high sample rates are required for real-time sampling of non-repetitive waveforms, but for repetitive waveforms - which, by definition, is what you'd look at on an analogue 'scope most of the time - equivalent time sampling means that the sample rates don't have to be anything like as high as 10 times the input frequency. I have an old Philips/Fluke "Combiscope" which, because of its age, uses equivalent time sampling, and actually, it's pretty good - there's no way it can be accused of "rubbish accuracy". Being a combiscope, you can switch between analogue and DSO mode with the press of a button, so if there is any doubt about the integrity of the display in DSO mode, an instant reality check is available. It's a nice 100MHz 'scope - I would use it as my default 'scope if it wasn't for the really noisy fan (worse than the Rigol once it's been on a while).
You mention cars, but didn't specify what sort - given that cars can cost anything between free and several million, we'll have to "park" (groan!) that...
Having said all that, for the sake of balance, we do have an Owon at work - can't remember the model number, but it's quite old now. Now that really is a very bad example of the breed - as I said to my colleague before he bought it, it was in the CPC clearance section for reason! There's lots of damning things I could say about it, but it wouldn't be fair or right to do so without reporting the model number and including specific facts supported by photos and perhaps a few links to videos and reviews that back up what I'd say.
I have no problem with criticism if it's measured and supportable. Sweeping (sorry - bad pun!) generalisations, however, are much less welcome. Sorry to moan - I try to let it go most of the time, but if I don't pipe up now and again, it begins to look like that style of posting - which can be rather off-putting, especially to newcomers - is tacitly accepted or even encouraged here.
