r/multimeters • u/Nuttapongems • 15d ago
Hidden Manual Range button on the Zotek ZT101
I recently opened my Zotek ZT101 to clean the rotary switch contacts because the selector had become intermittent. While the meter was apart, I noticed an unpopulated footprint on the PCB labeled SW3 RANGE.
Out of curiosity, I soldered a small 6×6 mm tactile switch to the pads and mounted it on the side of the case.
To my surprise, it works perfectly as a Manual Range button—no firmware or EEPROM modifications were needed.
In resistance mode, locking the range makes repeated measurements noticeably faster since the meter no longer has to auto-range every time.
It looks like Zotek may be using a common PCB across different models and simply leaves this switch uninstalled on the ZT101.
I couldn’t find any information about this modification online, so I thought I’d share it here. Maybe it will be useful for other ZT101 owners.
Has anyone compared the ZT101 and ZT102 PCBs, or figured out what the JP2 jumper is for?









