How often do you use an oscilloscope? Analog? Or digital? Or both?

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I used an old Tek tube doghouse in the late 70s when the shop was in the garage kept me warm in the winter.;)

More modern times I used a old Tek 453 until I lost a channel about 10 years ago then picked up a tek 456 for $100 on
ebay and it still being used every day. BTW.. the old 453 still works otherwise. Cant go to wrong with a used tek.
I would be lost without mine.

Gary
 
I used an old Tek tube doghouse in the late 70s when the shop was in the garage kept me warm in the winter.;)

More modern times I used a old Tek 453 until I lost a channel about 10 years ago then picked up a tek 456 for $100 on
ebay and it still being used every day. BTW.. the old 453 still works otherwise. Cant go to wrong with a used tek.
I would be lost without mine.

Gary
I totally agree that you can't go wrong with buying a dirt cheap Tek on eBay, in fact I would advice everyone to own one, but those are basically useful only for one thing and that is as a "signal window", thats it. If you actually want to be able to measure signals with it rather that just viewing what is going on inside the cable, you need something better, a digital scope or an analog/digital hybrid like the Tek 2465b/2467b which, in my opinion, is the best analog scope ever created by Tektronix.
I own a 2465a and I love it, I just wish it had the same screen as the 2465b
 
Yes, the 24xx series are great scopes. Wish I had one. Currently I use a BK 60 MHz analog and a Hantek 100 MHz digital. The analog scope is a good, not great scope. The Hantek is a fair, not good scope, but it is smaller and usually ends up being used due to little bench space. If I had a 2465, I'd be in heaven.
 
Just to add wrt costs that with any scope you should factor in cost of calibration services. May not need it as often as a professional outfit might. But definitely advisable if you buy a used scope on the eBay or similar.
 
Damn, thank you! I had never heard of this one, but it seems like the Keysight EDUX1052G is both analog and digital and has a signal generator all in one?

I may try to save up for that, I much prefer getting started with a one and done type thing until I know more about what all I need - and space is at a premium for me.

There's a long thread over at eevblog with people complaining that Keysight refuse to repair or support their products unless you're a company. So, individuals/ hobbyists are on their own if something goes wrong!

EDIT: Keysight officially lost the plot - don't buy if you're a hobbyist
 
Anyone who claims to be a tech and only uses a scope once in 14 years isn't a tech.
Sorry, but true.

No, I'm not sorry.
Until you have learnt all that square wave responses will show you on a scope, until you have learned to spot tiny RF bursts etc, all things that tell you where the problems are, you are failing your customers and don't even know.

All my test benches have the output of any unit going to four devices at once- a scope, a dB meter, a spectrum analyser, and an amp/speaker. I am getting all the info I need at once. ( the spectrum analyser and dB meter obviously going to 100kHz- above 20kHz is where you need to concentrate- amateurs do 20Hz - 20kHz )

I've had enough over the years of 'techs' who do a course somehere in electronics, buy an expensive analyser,
and then try to sort gear out and do it badly. The world is full of them.

Use a scope. Always. Have it permanently connected. It will show up things you would _never_have noticed otherwise, and if you don't use one, you will have returned 'repaired' or 'serviced' or 'restored' gear that is still faulty, and you won't even know.

But your customers will....

What spectrum analyser do you have that can go so low?
 
Low? How do you mean? 20Hz is a reasonable, common, starting point...?

I mean that all the hardware spectrum analysers I have found have a bandwidth that starts well above 100kHz and are not suitable for audio.
 
OK thanks. I was mainly referring to more modern SA. I have a DSO that has FFT but it's not that great so I've been looking for a dedicated audio SA. To be fair I wasn't expecting much from 8-bit resolution.
 
I bought a 50mhz dual trace from Radio World classifieds for $125.00. Enrved on the top of the bezel "NDC Radio Repair shop" That was when NBC had a radio network. Have had it for 25 yrs , it still works flawlessly.
 
I just picked up a Tektronix D10 with a 5A20N, a 5A18N and a 5B10N modules, including a Tronson TSG-17 frequency generator and a friggin HUGE CI systems 110volt transformer (I assume is for cleaning up power, its 100/110 and weighs a ton)
All for $30 on face-not-a-real-book marketplace...
Still have my trusty 2213 and recently got a cheap Dreamsource Lab DSLogic Analyzer Logic Analyzer for my Macbook...
I've found that all the the computer based digital oscilloscopes are windows based and run out of drivers and favor faster than an Avid product, which is pretty damn fast.
I Have a Bitscope DSO BU IT takes a bachelor's degree in confusion to actually operate it.

Analog oscilloscopes are easy to find if you're patient.
 
I mean that all the hardware spectrum analysers I have found have a bandwidth that starts well above 100kHz and are not suitable for audio.
Ah-yes- I found that....

I have an couple of old trusty Klark Tekniks, then an old DBX orange tube one, but they stop at 20kHz, so I found a Hewlett Packard 3561a that is excellent. It really shows up what is going on in a studio control room- all sorts of nonsense between 20 and 100kHz that you really needed to know about!!
 
"I've had enough over the years of 'techs' who do a course somewhere in electronics, buy an expensive analyzer,
and then try to sort gear out and do it badly. The world is full of them."

I'm sorry, but I disagree with most of what you said. You don't need an expensive analyzer and rarely do you need a scope for things that are 20hz to 20khz if you are not designing the circuit. If you are modding a simple design with high bandwidth opamps like say Jim Williams etc. sure you need a scope cause your modifications aren't compatible with the existing circuits, but needing a scope to sort simple opamp circuits not really. You can get by with signal injection a DMM etc. I have 3 scopes I've designed and built plenty of hardware. The only time I use a scope is for biasing circuits when I need to see what the waveform is doing like distortion "fet biasing" and filters etc." otherwise it's not really needed.
DI strongly disagree about using a scope. Crazy and arrogant and unprofessional not to.
Who in their madness would decide not to be informed of a problem with a peiece of gear?

I do, however, strongly agree with you about expenive analysers. That's my problem with crap techs- I know a few with AP's etc, and I've had them phone me to sort out psu ripple or somesuch and they know nothing, thier expensive analyser can't help, and they don't own a scope...! I have said for years that you buy an analyser when you are a circuit designer.

I like having four or more items connected together on a bench to show evrything at once.
The only time I change is when I want to measure noise floor etc, and I have only a chosen bit of test gear connected.
I always liked the look of a Lindos set, but when I watched a friend using his it only went to 20kHz, and he spent his whole time pressing buttons as he changed what the Lindos did...I don't have to do that either...
 
I mean that all the hardware spectrum analysers I have found have a bandwidth that starts well above 100kHz and are not suitable for audio.
Usually it is 10kHz not 100 kHz, but yes, most SA are not optimized for low frequencies. I was surprised with the GW Instek scope I bought recently, it has a built-in SA that is able to measure from DC up to 1GHz.

But, for audio, I am truly convinced that a simple audio interface and Matlab/Octave is the best thing for signal analysis, definitely much more versatile than the most advanced AP system out there. Granted, it won't be able to have such a low Noise and Distortion residual as an AP system, but what you can do with Matlab/Octave is much more and costs a mere fraction of the AP cost. You can manipulate signals in a way AP would only dream of.
 
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I've shared this story before, back in the 70s I bought an old used "Singer" spectrum analyzer ($700 used). This old school analyzer read up to 30 kHz with 50 dB dynamic range. Not very useful by itself, but I fed the distortion product output from my Heathkit distortion analyzer into the input of the SA to get a lot more resolution floor. In fact I could see the distortion introduced by the heathkit front end and managed to reduce that by running the Heathkit's nominal 0 level down at -10dB to clean it up. This could only display up to 30kHz but with low level resolution enhanced by the Heathkit gain was more than adequate for my budget circa 70s test bench needs. Funny this cost me around $1,000 total back then and felt like a bargain for what it could resolve.

Today you can cover this and more for peanuts.

JR
 
I'm a hack that mostly does kits and repairs things. I use my scope a lot.
I guess I should say scopes. I have an old Zenith Cathode ray scope. I find it useful for audio because it's instantaneous and the resolution is really good. But only for looking at things. The Rigol 1054Z is only 8bit true, but it's a lot better calibration than my 40 year old Zenith.
I can do a lot more with a 4 channel scope with math functions and such. But sometimes the old fashioned cathode tube single channel scope is better for seeing the actual shape of the waveform. That way I can see the exact place where the trimpot moves the wave into distortion.
On the digital scope there is a half second or so of delay. And there is always this kind of noise interpolated into the signal not matter what you do to match impedances and ranges.
To be honest, if I didn't also use scopes along with modular synths I'm not sure I'd be so quick to spend though.
For one thing it's kind of useless in audio without a bench power supply and signal generator.
I wouldn't get a scope without squaring away all those and a DMM first.
And I got 100% more engaged in making and fixing stuff when I got a temp controlled iron and one of those Panavise PCB holders.
 
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