A unique, feature packed Multimeter which has been developed with electronics designers and
hobbyists in mind. This multimeter represents two years of collaboration between EEVblog and UEI.
This is not a re-badged meter, nor a modification of an existing meter design. It was designed from the ground up to be a unique electronics oriented meter in the sub US$250 class price category.
Please note that being based in Australia, I have to use Kickstarter Australia who force pricing in Australian dollars.
Designed for electronics use, with unique features such as:
- Bluetooth connectivity (multi-device capability)
- Open Source Cross Platform application software (Android + Windows, and more soon)
- 15V Diode Test Voltage (useful for Zeners + LED strings etc)
- VA Power measurement
- Low Burden™ voltage
- Unique burden voltage display
- Micro SD Card data logging + firmware updating
Other major features include:
- Dual 50,000 count display with bargraph
- 0.05% + 5 Basic DCV Accuracy
- Auto-Hold measurement
- 600V CAT-III with independent UL 61010 certification by ETL
- Safe operation through HRC fuse + TVS + PTC + MOV + Diode Bridge protection
- AD8436 >100KHz True RMS
- 4 x AA battery powered with 500+ hr battery life
- Compact design - 84 × 165 × 59 mm (W × L × H)
- Hackable ST ARM Cortex M3 processor (S-LINK/V2 programmer interface inside)
- Hycon HY3131 chipset
- MAX4238 Low Offset Amplifier for current ranges
- SD Card firmware update
- Full Open Schematic available
- 8ppm ADR3412 voltage reference
The user manual with full specifications can be found HERE
The meter is manufactured by UEI Test Instruments, a reputable US based designer and manufacturer of high quality test gear. The design work was primarily done by UEI, but with a great deal of design input and direction from Dave. The meter is manufactured in South Korea.
The meter features the same MAX4238 chip used in the EEVblog µCurrent™ product to give lower burden voltage than typical meters.
You can read all about Burden Voltage in Dave's article HERE that was published in Silicon Chip magazine.
NOTE: EU shipping, as many people have asked.
I am talking to a test equipment company that have offered to do re-shipping in the EU for me, so hopefully the customer can avoid any import taxes.
But please note this is not a guarantee, it's just to say I'm investigating and trying to solve this issue for backer in the EU.
My backup plan is to ship on my DHL Express Courier account from Australia, so import taxes may apply in your country, so please take this into account as a worst case.
Risks and challenges
Like all hardware projects, hardware is hard, and "sh!t happens".
The 121GW has already passed ETL, FCC, and CE testing and we have the certificates. No worries there.
The 121GW design is ready for production, we have 50 early production units in-hand and going to EEVblog supporters. But that doesn't mean there is zero risk of a hardware issue that we haven't found yet. Such a hardware issue if found would likely result in a PCB re-spin and subsequent delay to full production.
The firmware in the 121GW is updateable by the user via SD card, so it's easy to fix bugs, and to add and polish features etc.
Any risk would come in already shipped units if we find an issue with the bootloader code. This would require a ST Micro programmer and header cable. But the bootloader only controls the LCD, buttons, and SD card routines, so this is unlikely.
The application software is still under development, and although it has been written to be as cross-platform as possible, we have not tested, iOS, Mac, or Linux compilations yet. Only Windows and Android have been tested. Bugs remain as of writing, we are working on those.
It's fully open source though, so you can take it and run with it.
So there could be issues here that delay introduction of software on those platforms not supported yet.
I guess that South Korea getting attacked by North Korea is a possibility?
The 121GW is made in South Korea, so yeah, that could potentially be an issue maybe?
Otherwise, regular production line caveats apply.
There are currently two components identified that have long supply lead times, and whilst we have factored this into the delivery dates for the given numbers, this is not within our control, and parts could be delayed longer than expected.
The campaign goes gang-busters:
Learn about accountability on Kickstarter
If we get a million backers then Dave will have a heart attack and this could delay things significantly whilst he's in hospital recovering.