K8009 seconds inaccurate

Dear Sirs,

I have purchased your kit “Multi Functional Clock Display – K8009”. I have assembled the kit and it works ok. However I tried to calibrate the clock time base using CV1 (Time Calibration) and using a frequency tester the maximum period I can measure is 15623.493 microseconds and the lower one is 15619.952 microseconds. In both measurements I have a difference of a +0.45 additional second per hour. I followed all the instructions but can not calibrate it to be more accurate. I would appreciate your help to know how to achieve better results. I am very pleased in general from all your kits. This is not the first kit of yours that I assemble and all until now have been very good.

I thank you in advance for your assistance. Looking forward to your reply.

Marios Andreou

Sorry, we have no experience with this problem.

Apparantly you cannot achieve 15.625ms, so the clock is too fast.
Try replacing C6.