I have tried to calibrate the blood pressure function but have been completely unsuccessful.
Shortly after I received the watch, I ran through the process ok but did not have a machine to measure the blood pressure.
I have just tried to calibrate the watch at the doctor's office with a machine but gave up after 5 attempts as it repeatedly failed with a weak signal error.
I have tried over a dozen times at home since with the same error regardless of how tight or loose the band, where it is placed on the arm.
I even tried putting the watch on the inside of my arm to no avail.
The only change between the successful run through without the machine and the attempt with the machine is I updated the software on the phone.
Oh, and the watch refused to accept the PIN last night, (first time I took the watch off to charge) to unlock and I had to do a restart.
I have the same experience with the blood pressure monitor and the blood oxygen reading neither test completes and each time it is either a weak signal or that I need to move the wat h to a better position for the blood oxygen reading.
It's is a little disappointing considering devices that cost less than $50.00 can produce consistent results even though they may not be accurate.
Same issuehere. It used to work fine but had to reset my watch after it locked up. Now I struggle to calibrate the BP measurement.... Always says "Weak signal" unless I tighten the strap super tight. Eventually got there but it is not right that it has to beso tight.
