HeadsUp RC is no longer around of course. It was a USA supplier anyway - so sorry to our US cousins but not much use over here.
I have read parts of the year old thread ... If a motor is Pulsing - that could be the ESC going into LVC ... Low Voltage Cutoff ... if user sets it that voltage reduces - what happens is that when ESC reduces power to the motor, the battery recovers silightly and ESC then delivers full .. but of course that causes voltage drop and ESC actions ereduction again ... this happens literally rhythmically and appears to be pulsing. I have two models that do this ... never bothered to program it out as it actually is not so bad ... I hear the pulsing - I reduce throttle and line up to land. 3.7V in my mind is too high a setting and I would suggest 3.3 or 3.4V ... why ? When the battery is delivering power - it suffers voltage drop. It is NOT the actual battery level - but a lower level due to demand on it and Internal Resistance. If you set your alarm level too high - you will get very short flight times as the voltage drop hits. Lower the alarm setting and your flight times become much better while still protecting the LiPo. Setting at 3.3 - 3.4V is not bad as the battery will usually recover 2 or 3 points once rested ... This is easily checked by setting your alarm and then after a flight where alarm sounds, land ... measure immediately the voltages... let battery rest and cool ... measure again. If the original data refers to the typical Turnigy 2826 2200kv motor, 2200 3S LiPo .... then unless its running a silly overlarge prop - which for the model stated is unlikely - you should be able to realise about 9 - 10 minutes at cruise and variable throttle. At full throttle less of course. That means pulling LiPo down to about 3.4V in flight. If the LVC is cutting in at 30secs flight .... then something is drastically wrong with setup. Most likely bad connection or LiPo battery is bad. Sorry If I've repeated what others may have posted and I know its an old thread ..
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