USB Oscilloscope

[Captn Dave]

I went over to a friends house today to troubleshoot a problem that was vexing me. Rather than use his Tek Oscilloscope we used his Parallax USB Oscilloscope. I was very impressed with the quality of the interface and the price. It was less than $150 shipped. Here is the LINK.

I really liked it but I have two complaints. First, it's only good for 20 volts. Nuf said. Second, it uses really basic probes. I'd like shielded 10x probes. It's far from a toy but inadequate for most tube work.

Another brand, Stingray, looks good too. And it has BNCs so you can use shielded probes but the max voltage is limited to 50V.

Are any of you using a USB Oscilloscope that you can recommend that is more appropriate for higher voltage audio work?

[janneman]

Originally Posted by Captn Dave

I went over to a friends house today to troubleshoot a problem that was vexing me. Rather than use his Tek Oscilloscope we used his Parallax USB Oscilloscope. I was very impressed with the quality of the interface and the price. It was less than $150 shipped. Here is the LINK.

I really liked it but I have two complaints. First, it's only good for 20 volts. Nuf said. Second, it uses really basic probes. I'd like shielded 10x probes. It's far from a toy but inadequate for most tube work.

Another brand, Stingray, looks good too. And it has BNCs so you can use shielded probes but the max voltage is limited to 50V.

Are any of you using a USB Oscilloscope that you can recommend that is more appropriate for higher voltage audio work?

Well, you can always use a 1:10 switchable probe to extend the input voltage.
Check out picoscope as well.

jan didden

[Arnulf]

Originally Posted by Captn Dave

I was very impressed with the quality of the interface and the price. It was less than $150 shipped.

Ouch, double that price and get 10+ times more value for your money ? OWON DSOs (standalone units which can connect to PC if needed, they also come with something that resembles real scope probes by default) start at just under $300 for the 25 MHz (100 MSPS sampling rate) model, shipped, and I distinctly remember seeing even cheaper DSO variant somewhere (possibly with monochrome LCD instead of color ?) but I forgot the brand name. It started with a 'U', I believe.

1 MSPS sampling rate might just be enough for audio though, barring experiments with square wave signals.

[jrenkin]

I have one from Velleman. It was a bit more expensive, maybe $200+ and is rated for 30V. I have a 10x and 100x probe, so should be ok to even high voltages. It has 2 channels and a function generator (which has a 2dB drop around 10kHz, but otherwise is flat). It seems to work pretty well.

[chrish]

Check out Rigol. There is a software hack that turns the 50MHz to a 100MHz (they are physically identical units with a software switch and different pricing).

[jrenkin]

I would think 50MHz is more than sufficient for audio applications.

[SY]

On the face of it, yes, but... especially with a lot of high speed circuits (and high gm tubes), you can get oscillations much higher than 50MHz that nonetheless affect the sound. And digital datastreams are likewise fast-moving, especially when you want to analyze risetimes and ringing. 1

100MHz is a reasonable minimum, but 300MHz or higher is often useful.

[levelfive]

Originally Posted by Captn Dave

Are any of you using a USB Oscilloscope that you can recommend that is more appropriate for higher voltage audio work?

Hi, Dave

I have used Digital USB Oscilloscope (see Specifications). It's very easy to use and is not picky about the computer resources, so as not to depend on the parameters of the audio card. As advantage can also note the presence of galvanic decoupling.

This very well made device, with 15MHz bandwidth - exactly suitable for audio applications. The oscilloscope is supplied with a special software - I have used its successfully for THD measurements (you can see spectral analyzer screenshots here).

[wwenze]

100MSPS for $175 shipped

DealExtreme: $175.00 DSO-2090 PC-Based 40MHz 2-Channel USB Digital Storage Oscilloscope

[revintage]

What about this one? Sells for ca 190USD/140EUR ex. VAT in Sweden.

Velleman nv