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Zapper for a FET timer for Brushed 6/7mm Pager Motors

Ian Middlemiss produced his "zapper" in 2010 as part of his article "A very simple FET timer for brushed 6/7mm pager motors."


I'm not sure that low cost "circuit board" voltmeters were easily available in 2010 but Chris Grant made use of one in 2018 for his zapper. Chris said "I used a meter that I had which has a current readout which is not used. Small voltmeters can be obtained for about £3 online. I also used 2 switches (1 for the zapper and 1 for the meter) but both can be powered from one switch as shown on the circuit diagram."
The advantage of a readout is that you can be sure you are applying the appropriate voltage to each model whilst the dial requires careful estimation to repeat a setting after a change of model.

A very neat version from Dave Andreski in the USA

A rather less neat version from Tony Beckett, it does have a stop watch and a "storage area" for Bluetac, whilst the front edges are metal lined so that the timer can be shorted out and so stop a motor run early if just testing.

An on/off switch is needed but a press button one is a better idea as it is very easy to forget to turn the fixed switch either on or off.

Tony Beckett
March 2018