Don't forget that the instructions for using fly sprays are always to close the windows, spray the room and leave a while with the door closed then to vent the room. Most people madly chase the fly in vein looking for a direct hit!
spuds, I bought one of those tennis-bat-fly-swatters recently but no flashes or bangs when I make a 'direct' hit with target insect[ usually a gnat ]. Can I make any modifications to increase the 'Zap-voltage' delivered?
Nope, its a one zap voltage that kills all device. I think it all depends on how the flying insect lands or is attracted to the zapping mesh. Sometimes it can be rather spectacular, other times, just like a damp squid!.