Welcome! Log In Create A New Profile


Stand for USB oscilloscope with tablet

Posted by leadinglights 
Stand for USB oscilloscope with tablet
January 22, 2020 02:49PM
A few days ago I noticed that my oscilloscope was distinctly unwell with noise on the trace even when nothing was connected. As it is often difficult to find and fix the cause of noise problems in modern equipment I set about finding a quick and cheap replacement. I had read about the Hantek 6022BE USB oscilloscope so I sent for one from Amazon and kitted it up with a Nexus 7 tablet as a display. The addition of HScope software (the provided Hantek software sucks) and I had a very serviceable scope albeit with some operational problems.

The Nexus 7 is a splendid small tablet with excellent resolution and works well but it was awkward to use lying flat on my workbench and, largely due to my fat fingers, it was hard to get the cursors to go where I wanted them to - there was a strong need for some kind of stand to hold the display.

The ergonomics of this layout is quite pleasing: The display can be tilted to a comfortable viewing angle and the oscilloscope is mounted on the same stand to give some weight. Both probes and a stylus (to get around the fat finger problem) are held in a block separate from the scope/display which can be places wherever is convenient. It did take a wee while to get the hang of setting the sweep by calling up the number of samples per second and using the "two fingered pinch" to get the horizontal display where I want it. To have lost the last traces of the twiddly knobs that graced old scopes is sad, but only because I have an inner Luddite who also misses the crank handle, choke button and quarter lights on cars.

The Hantek 6022BE can draw its power from the tablet or Android smartphone it is connected to but that can flatten the battery quickly. To get around this there is a second A-Type USB connector which can be connected to an external source of power. I have used a power bank which also reduces the chance of earth loops interfering with the signal. An OTG connector will also be needed to connect the Micro-USB B connector to the main lead.

Downsides and things that haven’t worked too well: You have to disconnect the scope from both the powerbank and the tablet or it will drain them down – there is no off switch. I wish that I had incorporated some cable stays on the frame as they get all over the place. Havings said that, the stand for the scope probes, stylus etc. works better then just leaving them loose on the workbench.

I have put STL files on Thingiverse along with STEP files so that the design can be modified for different displays. My shopping list was:

Hantek 6022BE from Amazon £55.99
Nexus 7 phone (second generation) I have had since about 2014 mainly for Kindle duties.
150mm USB OTG adapter cable (in my box of strays and waifs)
HScope software by MartinLoren licenced through Google Play £9.99 (single trace version is free)
Power Bank 12000mAh from Amazon £13.99
ISOUL Fine Tip Stylus from Amazon £6.95 (useful for controlling cursors down to pixel level)
Matte black PLA filament from Filaprint (prints well and has a cool "Assassins Guild" vibe)
35mm wide Nylon strap and clip salvaged from a redundant rucksack.
Odds and ends: 8mm X 50mm bolt and nut, 6 off press-in brass inserts, sheet material for strap clamp and 6 3mm X 8mm screws.

I am pleased to say that my old oscilloscope is now feeling much better after using the new one to trace a bad connection.


Edited 1 time(s). Last edit at 01/22/2020 02:51PM by leadinglights.
Re: Stand for USB oscilloscope with tablet
January 25, 2020 05:20AM
Link to this on Thingiverse [www.thingiverse.com]
Also a change to the PDF document to show a possible change to take 10" tablets.

Sorry, only registered users may post in this forum.

Click here to login