While firing at a respectable 12.5W the SVD mod suddenly started buzzing low down on the battery compartment, I caught quite the spook seeing as Im using an efest 18650 purple batt, what with the latest efest batt scandal and all.
Probably the fastest batt change ever, but the batt wasnt even warm.
Finally I figured out what it is, the PWM runs at a low frequency (33hz?) which you can only hear if you hold your ear against the mod case while firing... but because of the poor tolerance of the threading on the telescoping batt tube, the lower tube piece is free to resonate like a loudspeaker cone.
A quick fix is to just press the bottom case section against the palm of your hand when its buzzing and it stops immediately.
I dont screw the 2 sections together vas, because I think that batt needs a bit of expansion space and dont want to dent the neg batt contact either.
Bottom line...its not some critical "throw the mod into the pool" event, ie not caused by the battery, for what its worth.
Probably the fastest batt change ever, but the batt wasnt even warm.
Finally I figured out what it is, the PWM runs at a low frequency (33hz?) which you can only hear if you hold your ear against the mod case while firing... but because of the poor tolerance of the threading on the telescoping batt tube, the lower tube piece is free to resonate like a loudspeaker cone.
A quick fix is to just press the bottom case section against the palm of your hand when its buzzing and it stops immediately.
I dont screw the 2 sections together vas, because I think that batt needs a bit of expansion space and dont want to dent the neg batt contact either.
Bottom line...its not some critical "throw the mod into the pool" event, ie not caused by the battery, for what its worth.