Inexpensive USB Oscilloscope / Logic Analyzer (under $200)
 

I satisfied a long-time dream of owning an oscilloscope, and got a logic analyzer with it :) It's the one advertised in Servo Magazine this month - Hobbylab PC USB Oscilloscope

So far I have only used the oscilloscope and spectrum analyzer function, but it seems perfect for hobby use and robotics.

Re: Inexpensive USB Oscilloscope / Logic Analyzer (under $200)
 

that is pretty cool. I have seen USB pod scopes and logic analyzers on ebay for $400 to $500 (new), that have better specs.

the scope bandwidth on this one is a little low (200kHz sampling rate). You can get used digital scopes on ebay for $200 with a 100MHz bandwidth.

I have been keeping an eye on these USB pod instruments. They are very nice if you have a laptop to run them from, for testing stuff in the field. It will be interesting to see if they make a dent on lab bench scopes, like Tektronix or Agilent equipment. When you are testing and debugging in the lab it is nice to have a separate display and knobs to twiddle on each piece of test equipment, instead of trying to keep multiple windows visable, and pushing slider knobs with a mouse.

For a FIRST team this is definately a great find!

Re: Inexpensive USB Oscilloscope / Logic Analyzer (under $200)
 

I highly recommend a tool like this, there are many different options out there. A nice one for learning is available from Parallax which comes with an "understanding signals kit."

I decided on a Bitscope which I have been very happy with (runs on both windows and linux).

Re: Inexpensive USB Oscilloscope / Logic Analyzer (under $200)
 

Ok it seems to me that most these board-type oscilloscopes run in the neighborhood on 200 kilosamples/second....

I use a techtronics runnining at 1 megasample/second. Are there any higher sample rate usb scopes out there? somewhere around the 750~1000kilosample range?

thanks,

-Q

Re: Inexpensive USB Oscilloscope / Logic Analyzer (under $200)
 

try searching ebay, both the current and the completed listings

I found one there spec'd with a 40MHz sampling rate, ebay listing: 290026298161

there is nothing stopping a USB pod scope from sampling at any speed you want, the USB cable only has to supply the data you see on the display, and you can only see screens change so fast before its all a blur.

Re: Inexpensive USB Oscilloscope / Logic Analyzer (under $200)
 

When I looked at this product, I was aware of the low sample rate - but it seemed more than adequate for hobby use and the robotic sensors involved with FIRST.

I successfully used it to (a) prove that pulses were being output by the 2006 Gear Tooth sensors, and (b) measure the pulses, verifying that they were 25 microseconds and 90 microseconds respectively, as the gear turns in opposite direction.

After using the tried-and-true method of "fiddling with the controls" ;) to get the proper voltage/time/zoom scale - the square pulses were seen. Moving the software trigger icon up out of the noise level and enabling the Trigger feature, the position of the pulse was 'locked' to a stable position on the screen for easy measurement. I could see that the pulse length and voltage amplitude did not seem to vary. Then I moved the measuring icons to mark the beginning and end of the pulse, and read the number of microseconds directly from a text field provided.

The unit answered all my questions - I'm happy!

Re: Inexpensive USB Oscilloscope / Logic Analyzer (under $200)
 

my Tek scope only cost $50 at the swap meet, but that USB scope sure looks more portable!

Re: Inexpensive USB Oscilloscope / Logic Analyzer (under $200)
 

There is nothing like a 535 for heating up the shop on a cold winter's day either. Nice buy, the cart alone is worth $50.

Re: Inexpensive USB Oscilloscope / Logic Analyzer (under $200)
 

I got one of these for Christmas, and have been loving it ever since... two channel oscilloscope, Arbitary Waveform Generator, Spectrum Analyzer, 16ch Logic Analyzer, programmable clocks... the thing has everthing I could ever want. For $500, it's not quite what this post was looking for, but it's a little more than just an oscilloscope.

http://dynoninstruments.com/index.html

Sparks