Dave Young of Young Circuit Designs is publishing a series of articles and videos on element14 every other week to describe his experience in upgrading from his trusty Tektronix TDS2024B to a new Tektronix MDO3104. See his other articles in the series:

(a) Tek MDO3104 Scope Upgrade Series #1: The 70% Test with a Tek MDO3000

(b) Tek MDO3104 Scope Upgrade Series #2: Digital Decoding and Triggering for Analog Analysis

(c) Tek MDO3104 Scope Upgrade Series #3: Trace Persist and Analog Triggering

(d) Tek MDO3104 Scope Upgrade Series #4: Computer Connectivity and Remote Control




Setting up the connections discussed in this article are outlined in the following tutorials:

How to Connect a Tektronix TDS2024B to a Windows 7 Computer using USB

How To Connect a Tektronix MDO3104 to Ethernet and a Windows 7 Computer with USB

 

I've always found test equipment to be about 10 years behind the times when it comes to connectivity and the related user interface. When looking at new equipment I don't even consider the connectivity features as major since they are probably not worth the trouble. But despite my low performance expectations connectivity is a ripe topic for a scope upgrade series!

 

Both the Tek TDS2024B and Tek MDO3104Tek MDO3104 scopes have an integrated USB device port which is designed to connect to a computer for either command line based interaction or the use of Tek's 'OpenChoice Desktop' program. The Open Choice program is only capable of capturing screenshots and waveforms, or saving and loading scope setups.

 

The MDO3104 has added the extra functionality of LXI thanks to an Ethernet connection. In addition to being able to save and load waveforms and scope setups, there is a web-based user interface that allows for the full remote operation of the scope. This feature could be incredibly popular for engineers trying to collaborate over large distances, or if the engineer has a separate office desk from the shared lab.

 

Below is a video showing the features in action:

 

Connectivity

The most important thing is how easy it is to get the system connected. If I get fed up and quit because of some driver garbage that involves editing the registry there is a good chance that I'll find an alternate method to get the information I need from the scope.

 

Thankfully, following the directions was pretty straightforward. There was one small problem when plugging in the 2024B, but they call it out in the user manual and I was able to complete all of the connectivity setups within 30 minutes for both scopes. I don't know if the credit should go to Windows 7, Tektronix, or both but this was way better than the last piece of test equipment that I tried to connect to a Windows machine.

 

USB-Based Performance:

I consider this to be the USB-equivalent of the old GPIB communication system used by test equipment for decades: very straightforward and useful, but not without significant programming effort. I ran the standard OpenChoice Desktop program instead of writing my own interface. The controls were exactly the same for both scopes, which is nice for simplicity but I'm sure there was a lot of performance left on the table with the 3104. I did notice that the 2024B took a long time to acquire data where the 3104 was almost instant, but any other limitation was a function of the lightweight OpenChoice program and not the equipment itself. This type of connection would probably only be suited to an automated production environment for either scope.

 

Ethernet-Based e*Scope Performance:

The 3104 has the added functionality of an Ethernet port. It even serves its own web page so the only thing the user needs to do is connect to the LAN and then open up a browser on a computer to start talking. I am happy to say that my experience connecting was exactly that easy (although I had to read in the manual about the default username for login being 'lxiuser').

 

Once connected, e*Scope allows a remote user full control of the scope. There is even a 'Status' function that allows the remote user to see a description of which probes can be connected. The only thing the remote user can't do is manually move a probe on the circuit! Still, the usability of the scope over a browser is as bad as one would expect. No physical buttons or knobs makes for a horrible experience with navigating a scope trace. A huge touchscreen on my computer would have been a welcome addition since the controls were pretty small, and having to manipulate them with a mouse was a real PITA (I never thought I'd wish for a Windows 8 machine...). Again, functional but the web-based user interface looks like something that was designed 10 years ago.

 

    

 

Overall Review:

Both of the scopes performed equally when connected over USB, so a user that is unhappy with that performance would not benefit from a scope upgrade. However all of the functionality that was ignored by the USB connection was implemented in the Ethernet-Based connection. The full operation of the scope and some solid update rates made for a usable experience. I've helped students debug a circuit remotely over a webcam with a scope, and I would have LOVED to have the ability to take over the controls for a moment to show them how to use it.

 

For those that want remote access to the scope, it is certainly worth an upgrade. Otherwise, the normal local user would be equally happy with their existing unit.

 

Dave Young of Young Circuit Designs is publishing a series of articles and videos on element14 every other week to describe his experience in upgrading from his trusty Tektronix TDS2024B to a new Tektronix MDO3104. See his other articles in the series:

(a) Tek MDO3104 Scope Upgrade Series #1: The 70% Test with a Tek MDO3000

(b) Tek MDO3104 Scope Upgrade Series #2: Digital Decoding and Triggering for Analog Analysis

(c) Tek MDO3104 Scope Upgrade Series #3: Trace Persist and Analog Triggering

(d) Tek MDO3104 Scope Upgrade Series #4: Computer Connectivity and Remote Control