Recording time

[N_Cook]

I need to record the time a device (say A1) is switched on (nice if it
records the time the device is switched off).

I suppose that I need to wire the power cable through this device and from
this device connect to A1.

Is there any such device ? Or any other method of doing this ? (the device
A1 is at home).

Thanks.

A basic digital watch , assuming it starts from cold at 00:00 , 01 Jan 1981
or whatever .
And a latch to keep the power to watch going . Another watch and another
latch set by the first latch.
Then subtruct the hours and mins from the reading time

 

[sl@exabyte]

I need to record the time a device (say A1) is switched on (nice if it
records the time the device is switched off).

I suppose that I need to wire the power cable through this device and from
this device connect to A1.

Is there any such device ? Or any other method of doing this ? (the device
A1 is at home).

Thanks.