New scope for Xmas

[ed731pdh]

After getting highly miffed at the difficulty in getting my old analogue scope to look at digital signals and with Christmas rapidly approaching I decided "Hang The Expense" and treated myself to a Siglent digital storage scope.

A few weeks in and I don't know how I managed without one.

[Radio Fixer]

Very nice Ed and their prices aren't bad either. Never had a lot of use for storage capability.

Have fun

Gary

[ed731pdh]

Made life so much easier when chasing errant digital timing signals between chips but it came into it's own diagnosing recommended replacement parts for the video stage in the computer pictured were just not up to the job. A pair of ZTX313s went whuff and the recommendation was a pair of BC548s would do the job, which they didn't as the MHz rating was so low they just stuck their collective thumbs in their mouths and clammed up. A real pleasure tracing all the chroma signals etc. from chip to chip and how they interacted with the two transistors in the final mix stage to produce a composite signal. A pair of MPS2369 transistors restored full operation.

[Mark Hennessy]

What model did you go for?

I'm rather tempted by the new Rigol DS1054Z. It's certainly getting a lot of positive feedback at the moment, but it's very new, and issues have emerged (and been fixed with firmware updates). Stock levels are very low as well. I'll give it 6 months or so to settle down, while keeping an eye on the competition...

It's an astonishing amount of functionality for the money. At just shy of £300, it's more than £100 cheaper than a Fluke 87V DMM. I read somewhere that Agilent worked with Rigol a few years back - Rigol produced the entry-level Agilent models, and in the process, Rigol learnt a lot from Agilent... These cheap models are having a good effect on the prices of 'scopes from the big names - you can get a Agilent Keysight DSO1052 for not much more.

I like analogue 'scopes, but there are some tasks that require the storage of a digital 'scope. I have an old Fluke Combiscope, which switches between analogue and storage modes at the press of a button, and it is quite useful at times. But it is a product of the time. The sample rate is only 100MS/s, and as far as I can tell, it lacks the ability to "pan and zoom" the captured trace. To be honest, I bought it because I needed a decent 100MHz analogue 'scope, and I regarded the digital sections as a bonus. But what I do like about the digital processing is the measurement capability - even simple things like getting a direct (and pretty accurate) RMS voltage readout without having to reach for a calculator are really useful.

Based on my experience of digital 'scopes so far, I'd say that a digital 'scope compliments a good analogue 'scope, and a well-equipped workshop should have both (though obviously it depends on exactly what you're doing - YMMV). The thing is, digital 'scopes can tell lies. Just recently I was demonstrating this to a newly recruited graduate - during his degree course, he only used digital 'scopes and had never clapped eyes on a good analogue model. While assisting with a practical (which involved using a Tek 2465 to measure the length of a drum of cable), we got chatting about analogue vs digital 'scopes, and as the conversation developed, I decided to fetch an oscillator and a digital 'scope (just a basic Owon model) to demonstrate aliasing. He was somewhat shocked by this! As always, you have to know your gear

All the best,

Mark

[ed731pdh]

It's a Siglent SDS1102CML model, comes with 2 x probes, reasonably written basic manual to explain the functions, and a software CD which I have not had the chance to go through yet. The first thing that strikes you about it is size, or rather a lack of it, 6" in depth if that. Build quality is quite decent for the price, no floppy plastic that's going to break within a few weeks of use. The TFT screen is very clear and sharp, especially as the older I get the more my eyes get lazy.

I did the usual looking around on the net for specs and complaints / faults before I decided to take the plunge and get one. OK, it's not going to set the world on fire with it's performance when compared to makers like Tektronic etc, but then it doesn't have that extra zero before the decimal point in the price. For what I'm doing, as a home hobbyist and odd repair work, it's good enough for me and my requirements. If anybody else is interested, website at http://www.siglent.eu/.

[ed731pdh]

Couple of extra photos of the scope screen and operation panel.

[Mark Hennessy]

Thanks for these additional images. It's certainly on my short-list, thanks to this thread

I like that it has separate controls for the two vertical channels. The Rigol DS1054Z has one set which control the currently selected channel - not a big deal, but it's an extra button press.

In timely fashion, Dave Jones has just released a couple of videos about the latest Rigol:

Brief features summary: https://www.youtube.com/watch?v=ETCOhzU1O5A

In-depth review (1 hour, 18 minutes!): https://www.youtube.com/watch?v=W2qdtQkBKhc

And he did a few a while back:

Tear-down video: https://www.youtube.com/watch?v=kb9P1Am9aFU

Reverse-engineering the analogue front end: https://www.youtube.com/watch?v=lJVrTV_BeGg

Jitter problems (now fixed with a firmware update): https://www.youtube.com/watch?v=kcOdzFaIYNE

Quick health-warning: not everyone appreciates Dave's style, but there's no doubting his industry experience or enthusiasm for sharing knowledge. I enjoy the bulk of his output, but if you don't like him, don't watch

Anyway, we seem to be living in a "golden age" for test gear, thanks to competition from the east. HP Agilent Keysight and Tek are reducing their prices in response, should you want the comfort of a "big name" (not that Tek are really in the game at the moment, sadly), but the new upstarts are producing quality products at unbelievable price points. For those who are new to the game and aren't sure about committing a few £hundred to the hobby, the kits from eBay are an amazing way to get started (just look at Alan's LCR meter!). We've never had it so good

Thanks once again,

Mark