I was looking for a timer that can do 5 minutes off/1minute on.
Hard to find for a low price, and even harder to find for 220/240.
So I modified one of those timers that you can plug in.
Very cheap at Home Depot, Target, Walmart, etc.
The black pins can be pushed up, and every pin pushed up stands for 15 minutes that an appliance that you plugged in gets no electricity.
In other words, if you would plug in a pump on it, the pump would not work for 15 minutes at the times that you pushed up the black pins.
Not all of them are the same outside and inside, but the principle is the same.
Once you open them up the inside will be visable.
In the lower right corner you see the box with the gears.
That is where you can make an easy modification.
The basis of how such a timer works is that a tiny electromotor spins very fast.
Through a set of gears the speed is reduced, like in a transmission or gear box in a car.
In such a way that the last gear on the end of the line in the system (the blue one that sticks out) turns around in such a slow way that it makes the outside clock (the bigger black/white wheel with the pins on the outside) turns 360 degrees in exactly 24 hours.
By removing one of the wheels in the gearbox, the result will be that blue gear will turn faster.
For example in such a way that the black/white wheel will turn 360 degrees in just 1 hour or half an hour.
Normally your timer has 96 periods of 15 minutes.
But after the modification for example 96 periodes of 30 seconds.
Before I start posting more pics, I would like to know if anyone is interested in how to modify.
I don't want to mess up this thread just for nothing.