Do you need both analogue and digital scopes for your lab?

[raymond2000]

Hi do you need both analogue and digital oscilloscope for electronic hobbyist lab, I have an HP 65600a, and there are some good priced analogue scopes on eBay.
Watching some YouTube tutorials videos and reading some discussion from this blog, have highlighted some characteristics that an analogue have, knowing that my digital scope is more than 20 years old, so does adding the analogue scope such as hp1740a complement my digital hp54600a scope.
Thank you

[mikeselectricstuff]

If you have a good digital with intensity-graded display & fast update , that's enogh, but an analogue can be useful if you only have a cheaper digital scope.
Cheap digital + used analogue will be cheaper than a good enough digital to not need the analogue.

[raymond2000]

Thank you Mike,
I am on a tight budget the Digital HP54600A 100 MHz + analogue HP1740A 100 MHz both dual channels. The cost is £180+£70= Total £250.
Is there a £250 good digital scope with your suggested specs that can replace these 2 scopes?

[c4757p]

No, there is not.

[raymond2000]

Thank you c4757p
So with £250 budget, the combination of dual channels Digital HP54600A 100 MHz + analogue HP1740A 100 MHz is the ideal option.

[nanofrog]

I am on a tight budget the Digital HP54600A 100 MHz + analogue HP1740A 100 MHz both dual channels. The cost is £180+£70= Total £250.
Is there a £250 good digital scope with your suggested specs that can replace these 2 scopes?

Unfortunately, No.

Given my budget, I'm taking the less expensive DSO + analog route as well (still need a DSO, but it will wait). Still need to go through the analog and do some work to it, and they're a lot more fun to play with IMHO anyway (I really like the tactile feel of real knobs & switches vs. soft keys and encoders). 

[raymond2000]

yes nanofrog,
it looks like it for me too       2 scopes better than one  

[jpb]

The drawback of analogue scopes is their size. My lab has to fit onto a small workbench (desk really) so size becomes a rather important consideration when acquiring new equipment.

If you have the room then there is a lot of bulky but quality kit from a few decades ago, I sometimes feel tempted when browsing e-bay but then I look at the dimensions! 

[Smokey]

There should really be an "Analog vs DSO" sticky somewhere.  It might even be the topic of a quick video.  There are a lot of good threads on this but it still seems to confuse people.

1) Make a list of all the things you CAN'T do with a cheap modern DSO.
2) Make a list of all the things you CAN'T do with an old used analog scope.
3) Notice the list for #1 is really short.
4) Notice the list for #2 is really long. 
5) Take the money you were going to spend on the old used analog scope and put it towards a better modern DSO.
6) ? ? ?
7) Profit!

Despite a lot of people pushing the analog scope route, I haven't seen a good list of things you can't do with a modern DSO but you can with a cheap used old analog scope that doesn't include only inferred results from specialized measurements on once really high end specialized analog scopes that your average person probably wouldn't need to do.

Going back to the cell phone analogy, say your daily driver phone is an ancient Nokia brick with no camera.  It makes basic calls but doesn't have a camera and that's a feature you really want.  Are you going to get the oldest stand alone digital camera you can find even though it is crappy by modern standards? And then carry around two basic outdated pieces of technology that together give you only the basic features you want even through you are compromising on both of them?  Or are you going to get one modern phone that has both those basic features but with modern quality, plus a HUGE number of other additional features on top of that?

(Once again, just talking actual performance here.  Nothing beats an old analog scope sitting on the bench, functional or not, for making your lab look cool.)

[HackedFridgeMagnet]

The old HP analogue scopes look good on your bench. Especially to non electronics people.

My HP1741A currently looks even better than normal, as it is in pieces. <sigh>

[raymond2000]

Yes Smokey having a new digital scope is good
For a starter, when the budget is tight for a beginner, any scope is good for learning       ; and having both is a bonus.
I liked the phone analogy    ; old phone + old camera combination is also achievable, the picture seems to suggest.

[nanofrog]

For me, in terms of where an analog scope is more favorable, would instances where you'd need more than 8bits of vertical resolution. Granted, there are DSO's that can do this natively, but they're rather expensive, and likely out of reach for a home lab (stand alone scope, not Picoscope or similar that requires a computer).

Audio would be a good example of this IMHO, and since there isn't a need for a massive amount of bandwidth, it's far cheaper to go with an analog model.

YMMV though, so the potential buyer would need to weigh their needs carefully, and determine what's the best use of their available funds.

[EEVblog]

Surely you can get a useful new DSO for £250
Even here in Oz you can get a useful 60MHz DSO for AU$269 (£183):
http://www.triosmartcal.com.au/1764-uq2062c-digital-oscilloscope-60-mhz-500-msas.html

Sure, not the best, but more than adequate as a cash strapped starter scope.

The trick with anaog scopes is not to pay anything for it!

Dave.

[EEVblog]

Thank you Mike,
I am on a tight budget the Digital HP54600A 100 MHz + analogue HP1740A 100 MHz both dual channels. The cost is £180+£70= Total £250.
Is there a £250 good digital scope with your suggested specs that can replace these 2 scopes?

Yes:
http://www.ebay.co.uk/itm/ATTEN-ADS1102CAL-100M-Hz-1G-Digital-Oscilloscope-7-LCD-/321063391763?pt=UK_BOI_Electrical_Test_Measurement_Equipment_ET&hash=item4ac0de9213
100MHz, 1GS/s, 40K for £239

The HP54600A is useless as a digital scope, it's only 20MS/s.

Dave.

[Smokey]

OMG that picture is almost exactly what I had in my head when I wrote that.  The phone is spot on.  My mental image had duct-tape holding it together though.  That's too funny!

Be careful with the "resolution" of an analog scope.  After all the trace is just an electron beam scanned across a phosphor screen.  In addition to the scan bandwidth, that beam has a physical width associated with it.  It has an inherent "resolution", and I'm not sure it's better than 8-bit digital.

As far as using an analog scope for audio, it's true you can determine a lot about signal quality that way, but DSO opens up HUGE other analysis options for audio with the math functions like FFT.  That will tell you way more about audio quality than just looking at a section of sine wave, even with a cheap digital FFT.

[raymond2000]

Thank you Dave i recently purchased an HP54600A DSO around £180, in very good shape, with original folders and floppy disks, its dual channels 100MHz. The rest of the specs are in the manual, and i don’t know what they mean, will learn and find out with time.
I will have to upgrade , the ATTEN scope have the modern scopes specs and it is in that price range, thank you for the advice Dave.

[raymond2000]

OMG that picture is almost exactly what I had in my head when I wrote that.  The phone is spot on.  My mental image had duct-tape holding it together though.  That's too funny!

 it shows you, Necessity is the mother of all invention   

[raymond2000]

As far as using an analog scope for audio, it's true you can determine a lot about signal quality that way, but DSO opens up HUGE other analysis options for audio with the math functions like FFT.  That will tell you way more about audio quality than just looking at a section of sine wave, even with a cheap digital FFT.

Thank you, I’m learning a lot from you experienced specialists, appreciate your inputs   

[EEVblog]

Thank you Dave i recently purchased an HP54600A DSO around £180, in very good shape, with original folders and floppy disks, its dual channels 100MHz. The rest of the specs are in the manual, and i don’t know what they mean, will learn and find out with time.
I will have to upgrade , the ATTEN scope have the modern scopes specs and it is in that price range, thank you for the advice Dave.

The two key figures are the sample rate in MS/s and the memory depth.
The HP54600A only has 20MS/s, that makes this an ancient and fairly useless digital scope by modern standard, as it only has a single shot bandwidth of 5MHz tops, essentially not worth having on your bench apart from nostalgic value.
And that is a very common beginner mistake. They think the 100MHz bandwidth is the same as a modern 100MHz bandwidth digital scope, but it's not, that only applies to repetitive sample mode, and not to single shot waveforms.
Of course it's better than no digital scope at all, but you can do much better for your money.
Sell it and get a cheap modern DSO, it will be infinitely more useful.

Dave.

[raymond2000]

The two key figures are the sample rate in MS/s and the memory depth.
The HP54600A only has 20MS/s, that makes this an ancient and fairly useless digital scope by modern standard, as it only has a single shot bandwidth of 5MHz tops, essentially not worth having on your bench apart from nostalgic value.
And that is a very common beginner mistake. They think the 100MHz bandwidth is the same as a modern 100MHz bandwidth digital scope, but it's not, that only applies to repetitive sample mode, and not to single shot waveforms.
Of course it's better than no digital scope at all, but you can do much better for your money.
Sell it and get a cheap modern DSO, it will be infinitely more useful.

Dave.

Yes i will sell it and upgrade, thank you Dave for the advice, certainly its more clearer for me now.
 i came to the right place to ask for advice , got the right answer.
Thank you for the inputs   

[nanofrog]

As far as using an analog scope for audio, it's true you can determine a lot about signal quality that way, but DSO opens up HUGE other analysis options for audio with the math functions like FFT.  That will tell you way more about audio quality than just looking at a section of sine wave, even with a cheap digital FFT.

True.

But given the cost of a 12bit DSO (best of both worlds), it's far easier on my wallet to have a used analog (have a 2445B) + decent DSO.  Not as convenient as a single 12bit DSO, but is an acceptable compromise IMHO (and provide a lot of capability for the funds vs. just a DSO or analog scenario). 

[jucole]

A couple of years ago I bought a Trio CS-1577A (35mhz) and a HP1661 AS (250Mhz)  they were £25 and £75 from Ebay;  But 2 years on, the HP is just a pain in the arse as the memory depth is so small;  you know, if a Hackerspace opened where I live - I think would take them down and leave them there! ;-)  I'm currently looking for a modern DSO for my next set of lab gear projects; one with I2c is a must have!

[Smokey]

I bet a lot of beginners get this analog scope thing from that one drive time rant suggesting everyone get an analog scope.  It might be time to do a follow up video and clarify when that's actually appropriate.  Maybe when an older DSO compared to a modern DSO is appropriate as well.  Like this, it's not always obvious and may be misleading people into spending money they could be putting towards a better piece of equipment. 

[EEVblog]

I bet a lot of beginners get this analog scope thing from that one drive time rant suggesting everyone get an analog scope.  It might be time to do a follow up video and clarify when that's actually appropriate.  Maybe when an older DSO compared to a modern DSO is appropriate as well.  Like this, it's not always obvious and may be misleading people into spending money they could be putting towards a better piece of equipment.

I do recommend every beginner has an analog scope for learning, if they can get it free or cheap enough. That advice remains true regardless of what DSO you have or haven't got.

I do not recommend anyone buy any DSO that is not "real time", old or new. i.e. "real time" is one that has at least 4-5 times the bandwidth in sample rate. I'm pretty sure every new DSO on the market now is real time, but cheap portable ones ones like the DSO Nano are usually not.
With an old 2nd hand DSO, it's almost always not worth buying, when compared against a new modern cheap DSO.

Dave.

[FenderBender]

I guess it depends on the price. If you can find a good working analog scope for less than..I don't know, $50-100, I'd say go for it, but don't go spending $400 on an analog scope that was state of the art...35 years ago. They are great pieces of equipment, but it's not fun finding unobtanium parts and trying to fix the old buggers.