The classic edition is the one that started it all.  I believe that a hackable bare-bones timer is perfect for some situations.

Status: Completed – archivedtindie-logo


  • ATTiny85 Microprocessor
  • Arduino IDE compatible – limited command set on Tiny series processors.
  • 6 pin ISP header for programming
  • 4.5 amp rating -limited by trace thickness and width on PCB
  • Relay is rated for 10A so it should deliver good durability.
  • Features an input header connected to an Analog pin on the chip. This increases versatility.

Reason Developed: I needed a way to economize the use of my water recirculating pump while ensuring I had hot water in the house.  I designed and built this circuit to run for 75 seconds and then wait for 450 seconds.  I wanted to be sure I could modify it in the future if the need arose.  I built this project after taking the Advanced Arduino course from TXRX Labs.  Credit for design review and constructive feedback goes to the great folks at TXRX Labs.

Video: http://www.youtube.com/watch?v=0WkIpV5TWQg




Manual: tinytimer-classic-manual

Eagle Files: tinytimer-classic-eagle-files

Code: tiny_timer_classic-arduino-code

Board Layout and Schematic:

board-layout-tiny-timer Tiny-Timer-board-layout


Included Parts:


Assembly Photos:

tinytimer-classic-4 tinytimer-classic-3 tinytimer-classic-2

More Photos:

TinyTimer-Classic TinyTimer-Classic


tinytimer-classicb-4 tinytimer-classicb-5


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