I got a Chinese toy. £40 and big as a phone. Has a battery too, so I can use it on the car easily. It's also a signal generator, simultaneously. So I was able to offer a triangle to my amp, to look at crossover inaccuracy, when I was playing with the bias. I kinda like it, and while I was advised as you are here, I decided the generator function alone was worth £40, so why not?
If I ever need to eye up a CD player, it might fall short. I'm pretty much in the analogue audio domain though, with a few older items crossing my path, which this can poke at adequately.
This post is really about buying what you need. Maybe my toy scope could fix up an old analogue, and offer some rough calibration points. These cheap one's (<200) are often reviewed on youtube. I would cross reference a few of the ideas given, with the videos, and see how they perform in the tasks set them.
I'm not going to recommend the one I got, simply because it needs the instructions keeping. It has a momentary rocker switch, that can also be pressed down, and some features such as record and calibrate involve long holds. Or something like that. You see.. I can't remember. I know what function I want, but there will be some <back> and forth before I get there. The bench version has no sharing of button functions. You kinda know just looking at one, if you can work it or not. Unfortunately, I have no bench. I'm mostly mobile. Crawling around the carpet. So actually, my toy (dso510) meter is what I need.
Someone suggested a $200 meter. I would look that over. It buys a lot today. Unless it needs an IEC lead, because they start at $300 for a good one 🙂
If I ever need to eye up a CD player, it might fall short. I'm pretty much in the analogue audio domain though, with a few older items crossing my path, which this can poke at adequately.
This post is really about buying what you need. Maybe my toy scope could fix up an old analogue, and offer some rough calibration points. These cheap one's (<200) are often reviewed on youtube. I would cross reference a few of the ideas given, with the videos, and see how they perform in the tasks set them.
I'm not going to recommend the one I got, simply because it needs the instructions keeping. It has a momentary rocker switch, that can also be pressed down, and some features such as record and calibrate involve long holds. Or something like that. You see.. I can't remember. I know what function I want, but there will be some <back> and forth before I get there. The bench version has no sharing of button functions. You kinda know just looking at one, if you can work it or not. Unfortunately, I have no bench. I'm mostly mobile. Crawling around the carpet. So actually, my toy (dso510) meter is what I need.
Someone suggested a $200 meter. I would look that over. It buys a lot today. Unless it needs an IEC lead, because they start at $300 for a good one 🙂
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So I went ahead with the Siglent 814 - it comes with some standard probes but what specifically should I buy in addition to these? I just don't want to unknowingly blow this thing up before learning how to really use it lol - total newbie here when it comes to scopes. Planning on working on the 24v based pass DIY style amps but also my tube gear once I get some experience so will need something for higher voltage. Any recommendations? Any other "nice to have" accessories I should pick up while I'm at it?
We have some local electronics and HAM swap meets in my area so I'll keep my eye out for a nice analog scope this summer as well. I like the idea of learning how to use that in addition to a digital. Or maybe I'll restore my old boat anchor Conar 255
We have some local electronics and HAM swap meets in my area so I'll keep my eye out for a nice analog scope this summer as well. I like the idea of learning how to use that in addition to a digital. Or maybe I'll restore my old boat anchor Conar 255
I would restore your Conar 255. It isn't cutting edge, but it is a great learning tool. A nice Tek 2235 or similar is a great addition to the bench.
As for scope probes, absolutely! Do not even look at tube circuits without using x100 probes! Some signals are low voltage, but you just have to hit a high voltage point once to end something expensive. They can tell in service, so don't expect warranty to cover it.
Probes are not cheap for decent ones. My x10 500 MHz probes were $270 each (x4), then I had to buy x100 probes. Decent probes are not switchable. They have fixed attenuation. If you do get switchable probes, lock them in the x10 position with epoxy or something permanent. Melt with a soldering iron, just make certain they will never go into the x1 position. If you lose that x10 attenuation you can easily blow up a modern scope. It just isn't worth the chance.
As for scope probes, absolutely! Do not even look at tube circuits without using x100 probes! Some signals are low voltage, but you just have to hit a high voltage point once to end something expensive. They can tell in service, so don't expect warranty to cover it.
Probes are not cheap for decent ones. My x10 500 MHz probes were $270 each (x4), then I had to buy x100 probes. Decent probes are not switchable. They have fixed attenuation. If you do get switchable probes, lock them in the x10 position with epoxy or something permanent. Melt with a soldering iron, just make certain they will never go into the x1 position. If you lose that x10 attenuation you can easily blow up a modern scope. It just isn't worth the chance.
@anatech Which probe would you recommend for this scope - it can go up to 200MHz. I'm not familiar with which brand is worth while or not - Could you recommend something readily available either on Mouser , Digikey or even Amazon?
So a 100x for high voltage and 10x for every day / low voltage?
https://www.digikey.com/en/products/detail/cal-test-electronics/GE3231/6041715
So a 100x for high voltage and 10x for every day / low voltage?
https://www.digikey.com/en/products/detail/cal-test-electronics/GE3231/6041715
You have two voltage ratings to be aware of. One is the breakdown voltage of the probe. The second is the maximum input voltage for the oscilloscope. Pay attention to both.
A x10 probe is used mostly to isolate the circuit under test from the capacitive load from your instrument. The input impedance drops with frequency, be aware of that. The higher attenuation you have, the lower the frequency response will be. Normally passive probes are made to about 500 MHz maximum, you need active probes beyond that (= expensive!).
The frequency rating for the probe really depends on what you are measuring. If you will be measuring tube amplifiers, you shouldn't see much in the way of above 1 MHz signals. So buying to support the full bandwidth of the scope is wasting money if you don't need it. Keep an eye on input capacitance between probes in addition to voltage breakdown.
The expensive probes I have are not "daily drivers". Probes wear out through use, so I use cheaper probes with lower bandwidth for normal audio troubleshooting. If I am poking around in tuners and other high frequency circuits, out come the good probes.
A x10 probe is used mostly to isolate the circuit under test from the capacitive load from your instrument. The input impedance drops with frequency, be aware of that. The higher attenuation you have, the lower the frequency response will be. Normally passive probes are made to about 500 MHz maximum, you need active probes beyond that (= expensive!).
The frequency rating for the probe really depends on what you are measuring. If you will be measuring tube amplifiers, you shouldn't see much in the way of above 1 MHz signals. So buying to support the full bandwidth of the scope is wasting money if you don't need it. Keep an eye on input capacitance between probes in addition to voltage breakdown.
The expensive probes I have are not "daily drivers". Probes wear out through use, so I use cheaper probes with lower bandwidth for normal audio troubleshooting. If I am poking around in tuners and other high frequency circuits, out come the good probes.
In addition to high voltages, be carefull with the scope ground. It's common, for new users, to short non-isolated circuits, such as the mains voltage - never touch the mains with the probes. Same thing with some parts of switch mode power supplies, which are galvanic connected to the mains and cannot be touched by scope gnd. GND probe is connected to earth connector, so be careful here.
Some differential outputs, such as amp in bridge mode, might have problems if you connect the scope gnd to one of the leads (none of two are gnd). For measuring this type of amp, it's better to have differential probes (sometimes expensive for broadband) or you build your own cheap differential audio pre-amp with an opamp so as to convert the signal to a single ended output with gnd reference where you can safely connect the scope.
Right!
I've seen so many things damaged because the technician wasn't aware of what they were doing, they didn't pay attention. In other words, they were not thinking about the entire situation. When you see a smoking ground clip ... Or ex-test equipment because the ground traces vaporized - suddenly and loudly!
I've seen so many things damaged because the technician wasn't aware of what they were doing, they didn't pay attention. In other words, they were not thinking about the entire situation. When you see a smoking ground clip ... Or ex-test equipment because the ground traces vaporized - suddenly and loudly!
All this stuff becomes second nature if you pay attention. Mostly based on basic rules and common sense. Either that you you grow very old always doing thing wrong without a clue. lol!
Here you go:
https://download.tek.com/document/ABCs-of-Probes-Primer-60W-6053-17.pdf (stuff starting on page 40 about grounding is important)
https://download.tek.com/document/03W_8605_7_HR_Letter.pdf
https://download.tek.com/document/ABCs-of-Probes-Primer-60W-6053-17.pdf (stuff starting on page 40 about grounding is important)
https://download.tek.com/document/03W_8605_7_HR_Letter.pdf
If there's an adjustment, they are either X10 or x100 probes. It should say which on the probe.
But make the adjustment using the scope's reference square wave before using them for anything else.
https://www.tek.com/en/documents/primer/setting-and-using-oscilloscope
Use a plastic tool, which should come with the probe. It will look something like this one.
https://4gte.com/products/tektronix-003-0675-01-probeadjustment-tool/
But make the adjustment using the scope's reference square wave before using them for anything else.
https://www.tek.com/en/documents/primer/setting-and-using-oscilloscope
Use a plastic tool, which should come with the probe. It will look something like this one.
https://4gte.com/products/tektronix-003-0675-01-probeadjustment-tool/
x100 probes are not that common. Many are made for higher voltages (mine withstand 2 KV), so insulating surfaces are larger. Longer creep path. Chances are you have x10 probes.
If you see a switch, almost guaranteed you have a x1 / x10 probe. Lock that switch in the x10 position.
If you see a switch, almost guaranteed you have a x1 / x10 probe. Lock that switch in the x10 position.
Again, I'll have to haul out the scope and probes and have a look so I can see what I'm dealing with. I actually have some cheap 100X probes I bought on Fleabay.
Looking back in my memory bank, the first scope I purchased was a Tektronix 535 which had been liberated from Grumman on Long Island! It was wonderful and I learned a lot about cleaning the ceramics without damaging! Then kids started coming along so no more scope action (or golf) for a decade or so. I gave the boat-anchor to my high school in Cleveland. It was a really wonderful instrument.
You'll do well with the Sigilent. I use mine and a Tek 7704 most of the time.
You'll do well with the Sigilent. I use mine and a Tek 7704 most of the time.
My problem with the source in the DSOX1102G wasn't so much that it was a pain to set up. I got it set up to make an amplitude response measurement pretty quickly. But then I wanted to change the number of measurement points per decade and got stuck. Seriously? That's pretty fundamental. I also couldn't find the -3 dB frequency as I couldn't figure out how to change the Y axis. It's entirely possible that it was an issue with the user and not with the scope. I don't have a lot of patience for tools that are hard to use. But it's not exactly my first go-around with tools either. I've had no issue getting the -3 dB frequency of a circuit on an HP3562, HP3563, HP3577, HP35670, HP4194A, AP SYS-2700, APx500, or any other analyzer really...
Tom