Dear Judges…

A project log for 60MHz Bandwidth 250Msps Probe-Scope

The Probe-Scope is an open source 60MHz 250Msps oscilloscope probe with all guts built right in, that plugs directly into your PC via USB

Mark OmoMark Omo 08/25/2019 at 10:240 Comments

We know you have a lot of projects to get through, so we’ve put together this brief on our project as it pertains to the criteria of the Hackaday Prize.

First of all, what is the Probe-Scope? It’s an open-source oscilloscope running at 250Msps with 60MHz of bandwidth, in the form factor of a cable; imagine you cut the BNC end off of an oscilloscope probe, and replaced it with a USB port: that’s the Probe-Scope.

 i. Is this a unique solution to a particular challenge facing the world today?

The Probe-Scope is an innovation in the world of oscilloscopes, bridging the gap between the current low cost, low performance open-source oscilloscopes, and professional, expensive, closed-source oscilloscopes. 
The Probe-Scope grows as you grow, giving you as many channels as you have USB ports; it’s almost infinitely expandable to tens (or more!) of channels. We are shooting for every channel to cost around $100, putting it on par or even cheaper than the commercial closed-source solutions out there today.

Closed-Source Comparison:

Scope Model Probe-Scope RIGOL DS1054Z Siglent SDS1052DL Siglent SDS1202X-E Hantek DSO4102C
Price/channel $100 $88 $130 $180 $145
Open Source? Yes! No No No No
Bandwidth 60MHz 50MHz 50MHz 200MHz 100MHz
Voltage Range 300V Pk-Pk 300V RMS 300V RMS 300V RMS 300V RMS
Memory Depth (Per Channel) 16Mpts 3Mpts 16kpts 7Mpts 20kpts
Vertical resolution 8 bits 8 bits 8 bits 8 bits 8 bits
Rise time <5 ns 7 ns7 ns 1.8 ns3.5 ns

Open-Source Comparison:

Scope Model Probe-Scope Scope Fun OpenScope MZ
Price/channel $100 $375 $75
Open Source? Yes! Yes Software Only
Bandwidth 60MHz 100MHz* 2MHz
Voltage Range 300V Pk-Pk 40V Pk-Pk 40V Pk-Pk
Memory Depth (Per Channel) 16Mpts 64Mpts 32kpts
Vertical resolution 8 bits 10 bits 12 bits
Rise time <5 ns 3.5 ns 175 ns

*The Scope Fun has no anti-aliasing filter and therefore can give misleading results

Clearly, there is a large market gap for a low-cost, high-performance open-source instrument. This is the gap that the Probe-Scope is designed to fit in.

ii. How thoroughly documented were the design process & design decisions?

We have updates detailing every step of the design processes, everything from tricky design and analysis of high speed dividers to our process for laying out and assembling our boards.
We started with our detailed design and spreadsheets:

Then we moved on to a set of spread bench test PCBs to test all our subsystems:

And now we have our final PCBs hot off the press from PCBWay!

Here is a guide to all our updates:

Here is a guide to our GitHub Repos:

iii. How ready is this design be taken to market?

The hardware design is complete; our final PCBs were produced and assembled by PCBWay and functioned as expected right out of the box. We are planning on using the same design for volume manufacturing, with only minor changes to the connectors. The software is coming along nicely, more details on that in our next section.

iv. How complete is the project?

We have come a long way, having completing the following portions of the project in only 5 months:

From here this is our software roadmap:

We also have some stretch goals: