I used a PIC. It's one of the newer XLP (eXtremely-Low-Power) chips they make and has more pins than the original AVR. How is it different? Well...
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* Has both start and stop buttons
* More energy efficient
Uses 80% less power in (deep) sleep mode
Stop button saves running power
* PIC footprint is larger
* Less community support for PICs
Why: because I had access to a PIC programmer and I enjoyed making my own design. The addition of the (optional) stop button allows you to stop the sequence once you've successfully turned off the TV in question. This not only stop the blinking (optional) LED, but it saves power.
Design notes: I forgot the 100uF cap in my original PCB layout, even after I assembled the thing. So its placement is a little odd. Also, I've never used Eagle before. I learned it just so I can share the schematic, so go easy on my schematic.
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Recommended list of parts:
Ex. PART # DESCRIPTION Price
------------- ------------------------------------- -------
PIC24F08KA101 Microchip low-power MCU $2.94
1-390261-6 20-position IC socket (RECOMMENDED) $0.23
SR295E104MAR 0.10 uF, 20+V ceramic capacitor $0.13
(stock) 100 uF capacitor $0.11
(stock) 160 Ohm resistor (x2) $0.08 x2
MPSW01AG NPN 1W transistor (x2) $0.40 x2
751-1203-ND IR LED (wide output) $0.55
SFH 4511 IR LED (narrow output) $0.53
FCR8.0MC5 8 MHz resonator $0.33
BC22AAL 2-AA battery holder $0.71
PTS645SL43 6mm SPST tact switch, black $0.13
PTS645SK43 6mm SPST tact switch, red (OPTIONAL) $0.13
(stock) 100 Ohm resistor (OPTIONAL) $0.08
LTL-307GE LED (~2.1V forward bias) (OPTIONAL) $0.09
Specific part numbers are just examples. Other parts may work just as well. Prices are quoted from digikey.com and will be less expensive in larger quantities. (Prices are probably outdated by the time you read this, too, but they'll still provide a reference.)
Variant: This project was designed to run off of 3V (2-AA batteries) or 4.5V (3-AA batteries). 4.5V will offer increased power output, but I haven't tested it.