For the analogue delay line, I never bothered to figure it out. Never had a need. It was designed so you didn't miss the waveform at the trigger point. For those who haven't seen a delay line, it is usually a coil of shielded wire inside the scope chassis. The amount of delay wouldn't be very long at all. Useful only at very high sweep speeds.
For sure! I am more used to seeing the display begin on the left, not center. Curiously the default for most digital scopes is center.
I have used it set to both center and right if I was most interested in what happened before the trigger. This isn't the normal case.
Yup. You gotta know your tools!
For sure! I am more used to seeing the display begin on the left, not center. Curiously the default for most digital scopes is center.
I have used it set to both center and right if I was most interested in what happened before the trigger. This isn't the normal case.
Yup. You gotta know your tools!
The "basic problem" is your definition of an oscilloscope.
It is a device for viewing a change in electrical signal over time. It can be analogue, digital or in the case of the first oscilloscopes- electro-mechanical.
This is an early storage oscilloscope.
All oscilloscopes offer storage. The first were on paper/drums, CROs store by the persistence of the phosphor coating on the screen (otherwise we would see nothing at high sweep rates) and digital stores in silicon for as long as we want.
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Some years ago, I bought a DSO at a local second hand buy/sell store (don't know the english term). The DSO is a Fluke 196B Scopemeter with monochrome lcd display. It is portable because it has a build-in NiMH battery. I believe the scope when new, costed about 5000,- Euro back then 😶, I paid 250,- Euro. But after a while, it wouldn't boot up anymore, even with mains power (adapter) and I thought it was defective. I kept it in storage for some time. After renewed interest from my side to try to fix it, it appeared that the battery had died and without a functioning battery it would not boot. I was able to order a new battery (pretty costly) and now it works great, and portable. The scope has also a multimeter build in that handles 600V CAT-III and 1000V CAT-II, as well as resistance measuring and diode measuring. There is also a "recorder" function.
The dual channel scope probe inputs handle 300V CAT-III (as printed on the back), the probes that came with the device have 10:1 attenuation. So I could measure up to 3000V if I am correct? As I also tinker with tubes, it would be very handy to see waveforms etc. The specs say 200MHz, 1GS/s.
What I also would like to know is what is the difference between CAT-II and CAT-III regarding the voltage rating? Also, as it is portable, it has no earthed ground as is. What are the consequences/differences compared to a common scope which are likely earthed? Is this kind of scope useful for audio circuits?
Thanks from a noob in ocilloscope land....
The dual channel scope probe inputs handle 300V CAT-III (as printed on the back), the probes that came with the device have 10:1 attenuation. So I could measure up to 3000V if I am correct? As I also tinker with tubes, it would be very handy to see waveforms etc. The specs say 200MHz, 1GS/s.
What I also would like to know is what is the difference between CAT-II and CAT-III regarding the voltage rating? Also, as it is portable, it has no earthed ground as is. What are the consequences/differences compared to a common scope which are likely earthed? Is this kind of scope useful for audio circuits?
Thanks from a noob in ocilloscope land....
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Hi Horneydude,
I am familiar with those. I calibrated many. Not bad for rough field work. Yes, they were very expensive.
Your voltage breakdown with probes depends on the breakdown of the probes while keeping the voltage on the scope input terminals below their maximum rating. You have to look at both figures, the scope input is less than the meter input voltage rating, but I couldn't remember exactly what it is from memory. A 3,000V probe is larger than a standard probe and will probably be 100:1.
Sure, it is useful. Your minimum range, noise may well come into it. I think that is 8 bit, so a choppy waveform with the LCD display. Try it. If it works for what you need, great. I would also use an analogue scope, but try it. Compare with an analogue scope if you ever get the chance.
I am familiar with those. I calibrated many. Not bad for rough field work. Yes, they were very expensive.
Your voltage breakdown with probes depends on the breakdown of the probes while keeping the voltage on the scope input terminals below their maximum rating. You have to look at both figures, the scope input is less than the meter input voltage rating, but I couldn't remember exactly what it is from memory. A 3,000V probe is larger than a standard probe and will probably be 100:1.
I believe that is a safety rating between probe or instrument to operator. It's been a long time since I had to know that, so be safe and look it up please. Don't just accept what someone tells you.
Sure, it is useful. Your minimum range, noise may well come into it. I think that is 8 bit, so a choppy waveform with the LCD display. Try it. If it works for what you need, great. I would also use an analogue scope, but try it. Compare with an analogue scope if you ever get the chance.
Hi restorer-john,
What's your point? You've gone off on a tangent with that.
We call those chart recorders, not oscilloscopes. I had to certify those as well. More than familiar with chart recorders, are you? There is nothing wrong with the normal definition used by most people between the two types of waveform viewing instruments, three adding your mechanical one. Feeling good about yourself now?
My analogue scopes all had digital storage, and before that 35 mm film. Yup, a camera. My digital scopes also had camera backup when the software had issues.
What's your point? You've gone off on a tangent with that.
We call those chart recorders, not oscilloscopes. I had to certify those as well. More than familiar with chart recorders, are you? There is nothing wrong with the normal definition used by most people between the two types of waveform viewing instruments, three adding your mechanical one. Feeling good about yourself now?
My analogue scopes all had digital storage, and before that 35 mm film. Yup, a camera. My digital scopes also had camera backup when the software had issues.
Hi,
Sure it's usefull for audio, switching circuits (inverters, nobreaks etc), digital circuits etc.
200Mhz, 1GS/s and 8-bit resolution can do a lot for most of applications.
And the fact that it is battery operated, you can measure differential voltages such as in bridge power amp output and you can measure mains voltage since there is no GND reference - you can check nobreak, inverters output waveforms, for example, without the risk of shorting anything or hurting yourself.
Being 8-bit based, keep in mind that there are 256 levels, so S/N or distortion observable level is around -48dB or 0.4% in voltage.
Also, the display has limited resolution (not as good as a high end smartphone or workbench good oscilloscope, for example), so, if observing some "noise", you will not be able to know if the noise comes from the signal or if it is just lack of resolution.
If what you need to observe is very low level of noise, then this equipment is not appropriate.
It's not a lab equipment for observing minimum details such as 0.001% distortion, S/N -90dB measurements or things like that.
But, as long as you know the limitations, you can do a lot with it.
From the user's manual (comment in blue is mine):
The graph below is probably showing a perfect smoth sinewave signal, but the lack of display resolution will show the sinewave as a non smoth trace.
As long as you are not worried about smothness, no problem.
On the other hand, if you are troubleshooting a sinewave inverter and want to observe the superposed high frequency (let's say 40kHz) over the 60Hz sinewave resulted from the low pass filter, then you need a better resolution or you need to filter out the 60Hz first and then amplify only the high frequency. The creativity and experience with circuits can help to overcome some limitations.
I'm guessing @ctrlx wants something like this:
That should be possible if the scope will sweep fast enough.
Tom
Yes you can. There were several hybrid scopes early in the digital era. The Tek 7854 below is an example. Its max sample rate is 500 KHz but it can capture the screen at whatever the plugins can manage (mine stop at 12 GHz) and share via GPIB. (I have one for when my Siglent 1204-XE is not adequate to the job).
Attachments
More huge advantages of modern scopes
(1) Lots, LOTS cheaper.
(2) They work as a analog signal analyzer... press the button and it acquires the signal and you can see things like rise and fall times in the time domain. HP1980B was the first with its built in RAM. Before that we had to buy different boxes for frequency and time domain analyzers.
(3) Storage... storage... storage...
I love the old Tektroniks... awesome, but we had to use Polaroid cameras to do the "storage"... Now you know how old I really am...
I remember when we'd pay 10K for a scope for the lab... and HPIB was option 1.
The old joke was the menu at the HP HQ.... you got the basic entree menu, Option 1 was the plate, Option 2 was the utensils, Option 3 was the salad....
@1audio: I swore at an early hybrid 'scope in mid-80s. It was a Tek, although not nearly as fancy at that 7000 series. The ergonomics of using its digital department were appalling. We also discovered that its B time base was triggered after delay rather than running after delay, or perhaps it was just erratic. That caused a lot of grief when timing PAL video into a vision mixer. Nobody trusted that 'scope after that discovery. You have to be able to trust your test gear...
I've never sworn at an analogue CRO, but I have sworn (under my breath of course) at DSOs.
You have to have both (at least one of each, maybe more...) in your lab. Thing about a CRO is the controls are always where you left them and visually obvious, usually logical. You can operate them with your eyes closed. But DSOs have more "menus" than a large restaurant, rotary encoders and 'soft' buttons. I'm just old-skool I think.
The suggested rigol power supply is not bipolar , it is a 3 channel power supply. I would like to preserve the word bipolar for 4-quadrant power supplies, the ones that can sink and source current, or present a certain impedance when connected to a circuit, like a battery simulator in charging systems.
it was my first scope ever, after my failed attempt to build my own, using an old radar tube from army surplus.
I checked the imprint on the probes. They are Fluke VP200 10:1 probes. Rating 600V CAT-III and 1000V CAT-II. At the inputs the labels say 300V CAT-III. I guess high enough for the usual audio tubes and good to go. Yes, safety first. The limited resolution is pity but I guess with my level of electronic DIY I don't really need it, and there are other ways/instruments/analyzers to measure specific things like harmonic distortion and such. Nice to have though and looks good on the bench 😉
35mm film? I have never seen a scope attachment for that... Did it need a specific ISO? It would appear that all things analogue and vintage (check the prices for Sansui and Marantz 70s designs) are sought after by today's hipsters. The Polaroid Tek attachment doesn't appear to have joined the list. This one comes with some NOS film stock and he's asking $38 or near offer. You can thank me later -)
That's almost the 'scope I bought for £35 (mine didn't have the x5 gain switches). Twiddle the "TRIGGER LEVEL" control to see the sloping edge. Be careful not to overstress those four lever switches at the corners. Inside is a little gold-plated beryllium copper wiper that operates directly on gold-plated PCB contacts. It's secured to the plastic by two tiny studs that easily break, stopping the switch from working. The wiper can be Araldited to the plastic when those studs fail, but it's a fiddly job because you have to unmangle the wiper first and work out where it should be.