https://www.eevblog.com/forum/testgear/eevblog-121gw-multimeter-firmware-details/msg2828400/#msg2828400If you downloaded the firmware and its in a zip package, you have to unzip/uncompress the file first.
Its important to make sure the new firmware file on the SD card is named “EEVBlog.bin” with no spaces in the file name or the meter might hang and just display down.
If the batteries are old then you might want to make sure you have a fresh set of batteries installed before running the firmware update. I think I’ve read the newer firmware will check the battery level first, but i’m not sure about that.
1. Turn the meter off then hold down MEM and HOLD while turning on the meter. You will see IAP on the display.
2. Press the “SETUP” button and it will display “DOWN / DOUUN” and after 5 seconds the meter bar should start rising from the left to right.
3. Once the bar hits the end the meter will restart displaying the new version of firmware installed.
This whole process after it displays “DOWN / DOUUN” shouldn’t take more then 15 seconds.
Someday, maybe someday they will add a timeout to the firmware update menu so it will error out after say 3 to 5 minutes?
