EEZ Bench Box 3

by Envox

Modular, open-source test & measurement chassis

View all updates Dec 09, 2020

Your Feedback & Support

by Denis Kotlar (a.k.a. prasimix)

Dear backers and update subscribers,

Now that some time has passed, a good number of backers are already using their successfully assembled BB3s. I asked them to send me some feedback about the BB3 and I would like to thank everyone who responded. I wanted feedback for two reasons: your opinion will help us in our further work, but I also want to encourage all those who have subscribed to this campaign but have not yet decided to get one of the BB3 versions. So, below is some of your feedback (in alphabetical order):

Danielbriggs (via EEVblog forum);

In short: MASSIVE CONGRATULATIONS to Denis + the whole Envox team. These have really exceeded my expectations so far, and I feel there is much more to explore.

If I am honest I was slightly apprehensive on the module assembly of what would be received after all the "drama" from the assembler. However, the units I have received look perfect, no visible faults, and seem to work well and be manufactured to a high quality. (Not tested under load yet). So thank you for going through all that to get excellent units shipped with the kits.

Packaging is really excellent; nicely thought out and very compact.

The units are brilliant and have 100’s of features buried inside the UI, but at the same time, quick and clean to use + operate. The interface feels very intuitive, snappy, and smooth and all in all light years ahead of some products.

Elekorsi (via EEVblog forum):

Well i can say that i am using mine now for few days and i LOVE it. After some initial problems, we solved everything with Denis and i can just say that it’s been long since i have seen somebody so responsive and helpful. Hats off to Denis!

@FredTemperton (via Twiter):

Super impressed with the supply though! This thing is epic!

GatoAlfa (via email):

Hi I just received my BB3 with two DCP405 modules. I’m starting to use and I like it a lot. Thank you.

@gojimmypi (via Twitter):

I love my BB3! It’s an awesome open source programmable power supply

IanJ (via EEVblog forum):

Really enjoying my BB3, in the coming weeks it’s going to be used extensively whilst I test a whole production run of boards

MaxZ (via EEVblog forum):

Assembled my BB3 today. First impressions are pretty good so far. Here’s what I noticed (positive first):

  • This thing is FAST. Boot time, UI response time and especially control and read out of the outputs. I've been sitting here for a minute turning the thing on-off-on-off just because it can do it so fast. The fast readout is impressive, too.
  • Manual looks well made. A lot of pictures of the UI with markings for where to click what. Haven't used it a lot because IMO you shouldn't need a manual to get to know the basics about your device/tool/whatever. Manual is for the advanced and complicated stuff; the daily stuff should be self-explaining.
  • Many parts of the UI are well designed. Not only with regards to the previous point, but also with an eye on productivity. This was a big fear of mine; having a lot of features and a touch display is nice, but if it's slower to use than the good old 4 knob analog supply, it's annoying. Very happy to see that this fear did not become true for most parts.
  • Assembly was pretty straightforward. Big thumbs up for requiring only two types of screwdrivers, two types of screws (technically three if you count the two longer ones) and nothing else. No washers or clips or dunno what.
  • Packaging was pretty efficient. Everything protected and pretty much as compact as possible. These are the kind of details that give me the feeling that someone put effort and thoughts into it.
  • Putting those power supply modules into the bottom PCB was veery satisfying ;D
  • Look and feel during the construction was very good. There're only very few minor things that could be improved in my opinion. Like it!
  • Thaaank you for the option to turn off the beep sounds. Otherwise I'd have desoldered the thing sooner or later.
  • Not directly related to BB3 itself, but I can't emphasize enough how much I respect the effort prasimix put in the fulfillment of the Crowd Supply campaign. I really hope that in the end you didn't lose money on this; that's really the last thing you deserve.

@THag (via Discord):

Congratulations for developing such an awesome product and not giving up despite

every obstacle they could throw in your way.

@timonsku (via Discord):

Outstanding software, lots of capabilities and very easy to use

Special thanks go to the backers who decided to rate us on Trustpilot where we currently have 10 reviews.

We still need your support to achieve everything we set out to do. Recently, in addition to purchasing one of the BB3 kits, you can also help by donating to our Liberapay account. Any amount is welcome.

For the end of this update, just a brief reminder that in the meantime we have released several new firmware versions, the last one is v1.5 and we are currently working on v1.6. The firmware download procedure is explained in Chapter 13.

And to end with one tempting picture: the successful collaboration with the ULX3S team led to the prototyping of the "MCU" module, which also has an ECP5 FPGA that can mix video signals and display them in two places: TFT touchscreen and external HDMI monitor/projector. I believe that I will have the opportunity to report back soon with more interesting news.

About the Author

Denis Kotlar (a.k.a. prasimix)


$154,699 raised

of $85,000 goal

181% Funded! Order Below

Product Choices


Support EEZ Studio Development

EEZ Studio is a cross-platform free and open source BB3 development environment but also attractive SCPI controller that is used to access many T&M devices using SCPI commands. Its development and support cost us money and your donation will help us to keep it alive and kicking.


BB3 - Starter (Without Peripheral Modules)

A BB3 enclosure kit without bare PCBs but with fully-assembled core modules (AUX-PS, MCU STM32F7, and BP3C DIB 3-slot backplane). The Starter provides an environment for experimenters who are willing to build their own modules or who want a specific BB3 configuration (such as a six-channel BB3).


BB3 - Two Channel (Full)

A BB3 starter kit and two full-featured DCP405 single-channel (40 V, 5 A) peripheral power modules, including an AC/DC power module for each. A two-channel programmable power source with advanced features: remote sensing, remote programming, a down-programmer, and additional OVP (with crowbar).


BB3 - Four Channel (Full)

A BB3 starter kit, two full-featured DCP405 single-channel (40 V, 5 A) peripheral power modules, and one dual-channel DCM220 peripheral power module. Includes all three necessary AC/DC modules. This is the two-channel full kit, expanded to include two additional programmable power sources.


DCP405 One Channel Module (Full)

A full-featured DCP405 single-channel (40 V, 5 A) peripheral power module with remote sensing, remote programming, a down-programmer and crowbar OVP. Includes an AC/DC module.


DCM220 Two Channel Module

A DCM220 dual-channel (2 x 20 V, 4 A) peripheral power module and its AC/DC module.


Cable Set

Two pairs of high quality, silicone, color marked (black-red), 1 m connecting cables; a pair of clip-on probes; and a pair of insulated crocodile clips.


BB3 Enclosure & Bare Boards

A BB3 enclosure kit with a wire harness, nuts and bolts for the three core modules, a 4.3" TFT touchscreen display, an encoder knob, and an 80 mm fan. Includes a set of bare PCBs for building the three core modules (AUX-PS, MCU STM32F7, and BP3C DIB 3-slot backplane) as well as PCBs for building one DCM220 two-channel peripheral power module and two single-channel peripheral power modules (either the DCP405 or the DCP405B, as they can be assembled using the same PCB). Suitable for builders with the necessary skill, time, and patience.



Envox d.o.o. is home of the Envox Experimental Zone (EEZ), an open source initiative to bridge the gap between DIY / hobbyist / educational / low-budget and professional / commercial test and measurement solutions.

Denis Kotlar (a.k.a. prasimix)

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