Their demo video has the 'scope window sized about 1350x450px. It seems likely it could be displayed bigger. It can never (in our life) approach the 65,536 pixels of a 16-bit ADC.
If you're connecting to the computer via USB, I can vouch for these cheap little isolators -- they can seemingly do miracles in some test setups. I have used three at a time in some setups. Only work for FullSpeed (12Mbps), though, but good enough to pass 96kbps sampled USB audio.
Cheap USB Isolator
There are some USB3 compatible ones, but I haven't tried them (haven't needed yet, and they are pricey
iFi Audio Galvanic3.0 Isolation for USB 3.0 Digital Audio - Authorized Dealer | eBay
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I remember 320x200 (EGA) resolution on 13-inch CRT monitors connected to IBM PCs. That was very jaggy.
After a while we got 640x480 (VGA), which was still jaggy.
A few years later, we got 1024x768 (XGA) resolution. For me, that was the point where (with CRT monitors) jagged images stopped being a bother. With the soft-edged pixels painted by an electron spot, there wasn't really enough jaggedness to bother the casual eye any longer (though I'm sure graphics professionals would disagree vehemently).
My current Rigol scope with its 7-bit converters - only 128 steps - has worse - much worse - vertical resolution than the tragically inadequate 200-pixel vertical resolution of a 320x240 EGA monitor connected to a 1984-model IBM PC. Thirty years of progress in digital electronics all went towards more bandwidth for the Rigol, while display resolution actually went backwards.
But it doesn't take a lot more bits to make an enormous improvement. A mere ten bits of vertical resolution would get us to 1024 vertical steps, which is probably about the point at which jagged traces would cease to be a problem for most practical purposes.
I still have reservations about the sound-card-as-oscilloscope plan, but a big "Thank you!" to everyone for their helpful suggestions. (That USB-to-USB isolator board is a great find!)
-Gnobuddy
I actually have one, which I rescued from the recycling bin after it was chucked there by an employee from the electronics department of a local university.
It's huge, very heavy, and buzzes when plugged in, but it works.
-Gnobuddy
IMO, even for audio 200 kHz isn't really enough. When a circuit is behaving well, it's fine, but I've seen a lot of amplifiers oscillate well above 200 kHz, sometimes even above 10 MHz. Tube amps as well, 6L6s will have no problems oscillating at 10 MHz- hams have been doing it for decades.
There is one major downside to most 4-channel oscilloscopes on the market, and that's that most of them don't have dedicated knobs for each channel's vertical adjustment. It's a selector button and one knob for all of them. To me, this makes scopes like the 1054Z rather clunky to use IMO.
The quality of Tektronix is nowhere near what it was back in the 1970s, but we have a couple of fairly new Tek scopes at work and they're really pretty nice. The only thing I don't like is that because they have every bell and whistle imaginable, they are confusing if you aren't used to them. Also, let's not forget that Tektronix has made some amazing products and some real dogs over the last 40 years (and I'm not talking smart dogs like border collies). Some of their digital scopes from the 90s have not held up well and have awful user interfaces.
I have a 2235 and like it quite a bit, but there are a few things that aggravate me. The trace isn't as sharp as it really could be, and the vertical position controls are really twitchy even after cleaning. I'm sure that a lot of this has to do with it being an ex-university scope, and it's pretty worn out. Still, it triggers better than either of the other two analog scopes I have.
There is one major downside to most 4-channel oscilloscopes on the market, and that's that most of them don't have dedicated knobs for each channel's vertical adjustment. It's a selector button and one knob for all of them. To me, this makes scopes like the 1054Z rather clunky to use IMO.
The quality of Tektronix is nowhere near what it was back in the 1970s, but we have a couple of fairly new Tek scopes at work and they're really pretty nice. The only thing I don't like is that because they have every bell and whistle imaginable, they are confusing if you aren't used to them. Also, let's not forget that Tektronix has made some amazing products and some real dogs over the last 40 years (and I'm not talking smart dogs like border collies). Some of their digital scopes from the 90s have not held up well and have awful user interfaces.
I have a 2235 and like it quite a bit, but there are a few things that aggravate me. The trace isn't as sharp as it really could be, and the vertical position controls are really twitchy even after cleaning. I'm sure that a lot of this has to do with it being an ex-university scope, and it's pretty worn out. Still, it triggers better than either of the other two analog scopes I have.
I have this one:
https://www.amazon.com/gp/product/B06XZML6RD/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
Very happy with it.
https://www.amazon.com/gp/product/B06XZML6RD/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
Very happy with it.
Admittedly I do not own or know Siglent scopes, but I bought a Rigol DSZ1054 some years ago when there was offered some discount. Accustomed with real CRT scopes, I can't exactly say that this Rigol can be operated intuitively. Yes, it offers lots of gongs, bells and whistles, but I don't even know if I'll need all of them.
In conclusion, mostly I operate my old Hameg 412, 'cause my HP 104 mainframe that basically is superior by far shows some issues
.
Best regards!
In conclusion, mostly I operate my old Hameg 412, 'cause my HP 104 mainframe that basically is superior by far shows some issues
.Best regards!
Very true, but there are some relatively simple ways to check for that, not requiring the use of expensive high-bandwidth 'scopes.
The simplest is to bring a radio and / or TV near the test amp. Squeals and misbehaviour that disappear when the test amp is powered down are a pretty good clue that RF oscillation is occurring.
Another check uses a couple of 1N4148s, a low-pF coupling cap, and a DMM set to read DC volts. If there is substantial AC, the diodes rectify that to DC, which shows up on the DMM.
-Gnobuddy
Checking for it doesn't mean you can efficiently figure out where the problem is and fix it - a good 'scope is pretty helpful for this.
These days 100MHz is entry-level for a 'scope. High bandwidth would be anywhere from 500MHz to 100GHz - the latter being _extremely_ expensive.
People love to think they're "getting something for nothing" - even if the "something" is not actually of any use to them.Maybe this was the main drive for the well known hack to enable 100 MHz for the Rigol DSZ1054 scope
-Gnobuddy
People love to think they're "getting something for nothing" - even if the "something" is not actually of any use to them.
-Gnobuddy
True, but in many cases that extra bandwidth is useful. If you want to look at a 25 MHz square wave, for example, 100 MHz is really borderline. Only sometimes do we have to look at digital signals when dealing with audio equipment, but I won't say it never happens.
I for one have found my 100 MHz bandwidth of my Tek 2235 to be a bit of a limitation at times. Given the fact that it probably does have 10k+ hours on the CRT, that may be a factor (focus isn't great, especially at high sweep rates, and it isn't the focus resistors). It came out of a university EE department.
I think for 99% of what I do, a 20 MHz bandwidth would be fine. Still, at least in the US, the cost of a new 50 MHz scope has dropped down to about $200. I've passed up used analog scopes with 20 MHz bandwidth for $35 before.
I'm not a fan of a sound card as an oscilloscope. For a distortion analyzer, sure, since there aren't many better options that don't cost upwards of $3000. Even the QA401 is basically just a sound card. A decent sound card with a bandwidth greater than 20 kHz isn't much cheaper than a used oscilloscope with 1000 times the bandwidth, and the latter has a proper front end designed for the task.
IMO, we're only just getting to the point where digital scopes have the resolution to be really good for audio work. I've used a TDS2024 for testing power amps, but it's not ideal. I'm very tempted by the Siglent SDS1202X-E though.
Well, that hack enables also the software support for protocol decoding (serial, I2C, etc.) which I found very useful several times. Also for checking DAC/ADC master clock signals the extra bandwidth (gained by disabling the model-discriminating LPF) comes handy.
The Digilent Analog Discovery 2 is an interesting USB oscilloscope with 14 bit resolution. The software works on Linux. It has Network, Spectrum and Impedance analyzers.
USB Oscilloscope and Logic Analyzer - Digilent Analog Discovery 2
Not too expensive either, about the same as basic oscilloscopes.
This is definitely something I would consider in addition to a basic oscilloscope.
I've finally bought my first oscilloscope this year (had a really basic handheld and an old PC oscilloscope before). I went with the Siglent SDS1104X-E. It has four channels and some extra features that I'm unsure I will ever use. I bought a Siglent signal generator, too, so it has the possibility to make Bode plots (the oscilloscope drives the signal generator over USB). The problem in audio use is limited resolution, though. This is where an USB scope or soundcard wins many times over a conventional oscilloscope.
Now to high voltage measurement. Oscilloscopes are restricted by the electronics in the frontend, mainly the AC capacitor voltage rating (and of course other electronics as well). The cheap 100x probes I've seen for sale do not have voltage dividers built-in, which means that if you accidentally put the scope in AC mode, the oscilloscope input capacitor will receive the full voltage you are measuring! So keep to DC mode with such a probe if the voltage is higher than what the scope is rated for. A differential high voltage probe would be safer, though.
USB Oscilloscope and Logic Analyzer - Digilent Analog Discovery 2
Not too expensive either, about the same as basic oscilloscopes.
This is definitely something I would consider in addition to a basic oscilloscope.
I've finally bought my first oscilloscope this year (had a really basic handheld and an old PC oscilloscope before). I went with the Siglent SDS1104X-E. It has four channels and some extra features that I'm unsure I will ever use. I bought a Siglent signal generator, too, so it has the possibility to make Bode plots (the oscilloscope drives the signal generator over USB). The problem in audio use is limited resolution, though. This is where an USB scope or soundcard wins many times over a conventional oscilloscope.
Now to high voltage measurement. Oscilloscopes are restricted by the electronics in the frontend, mainly the AC capacitor voltage rating (and of course other electronics as well). The cheap 100x probes I've seen for sale do not have voltage dividers built-in, which means that if you accidentally put the scope in AC mode, the oscilloscope input capacitor will receive the full voltage you are measuring! So keep to DC mode with such a probe if the voltage is higher than what the scope is rated for. A differential high voltage probe would be safer, though.