# Repeat on/off delay Timer

#### wayneh

Joined Sep 9, 2010
16,102
FWIW, I use these. You can get them for less than $5 if you watch around. I've often wondered whether/how they might be hacked for switching DC loads. #### Attachments • 12.7 KB Views: 29 Thread Starter #### Etronic Joined Oct 7, 2011 127 wayneh Thanks for your recommendation. Where do you get them for$5.Plus you will pay more to ship it.If you order it online.
But? How accurate are they.Low price is always a great deal.
If they work. And are accurate to the MIN.

The one i pick up at homedepot is very accurate down to the MIN.
Small size.And all settings worked prefectly.Also i could bring in back,if it dosen't work within ninety.And get my full money back.

P.S. IF you locate some post it here.

#### Etronic

Joined Oct 7, 2011
127
elec_mech

Did you get my latest posted message.

#### elec_mech

Joined Nov 12, 2008
1,501
Hi Etronic,

Unfortunately, I cannot be of much help without seeing the circuit. Do you have a webcam you could use to take pictures or a simple video?

Alternately, could you draw the circuit and label the values of the components, especially the ICs? You could do this in Paint if you have a Windows machine: Start->All Programs->Accessories->Paint. Bill has some info on using this program for circuits: http://forum.allaboutcircuits.com/blog.php?b=49.

So you want to turn on and off a battery powered device that uses a 3.6VDC battery?

What is the battery voltage of the backup battery in the timer? I know the backup battery will keep the time if the wall power goes out, but I do not know if it will still turn the output on and off if there is no input power. This depends on the circuit.

You'll probably want a MOSFET in the end to turn the 3.6VDC device on and off since the timer probably uses a relay and energized relay coils could quickly drain a battery. If you're really lucky it might be a solid state relay which could work well, but mechanical relays are much cheaper, so that is probably what the manufacturer used.