LEAP Compact Professional Digital Chess Clock Count Down Timer PQ9912 / PQ9903A / PQ9907S (PQ9903A)

This is a review of PQ997SI bought this clock to use while playing go (i-go/baduk/weichi). It is perfectly adequate for this purpose with a sturdy rocker switch on top to control which clock counts-down to zero. We can set different amounts on each side at the start and optionally set whether an alarm sounds when the time reaches zero.It seems I am not the only one to have had a problem when I first inserted an AA battery and turned it on. I was able to set the starting value but this value ticked upwards instead of decrementing to zero. I thought the device was broken, particularly after I compared the behaviour of my clock with that on a YouTube video. I replaced the battery and turned it on again and now it behaved perfectly. I don't understand why the description says "It is a presettable count up / countdown timer" because I was never able to get it into the increasing mode again.There are two features of the clock that confused me and that I don't think I will ever use. - the first is called 'bonus'. If I set bonus to, say, 10 seconds in the setup then whenever the rocker-switch is pressed to start one of the clocks then this amount is added to the clock-value before it starts counting down. If the players played fast enough then the displayed time would continually increase instead of going down to zero. This may be perfectly normal to chess-players (I believe they call it 'increment') but it seems weird to me. - the second is called 'delay' and makes more sense. If delay is set to some amount, say 10 seconds again, then when the rocker switch is pressed to start a clock ticking downwards we first see a countdown of this amount (ie 10 seconds) before the main clock displays. This is to give the players time to record the move. I think, but I haven't tried this in practice, that if the initial starting-time was set to some very small amount then this mode could be used to time a novel blitz game of 10 seconds a move. Also, a start time of 5 minutes and a delay of 30 seconds would give something very similar to the times used for the NHK Cup Go tournament of 30 seconds per move and 10 periods of 30 seconds byomi.Addendum. The BGA uses a different form of byomi in tournaments: when the main time has elapsed then the clock is reset to a small amount such as 5 minutes and a set number of stones have to be played within this period. I have experimented and I believe that this clock could be used to implement this but it would be a little fiddly.