Error when compiling on Arduino Uno using IDE 1.6.8 about arduino HOT 7 OPEN

I got it working now after attaching an additional 220ohm resistor.Though the output have a number counter at the back example "Hello World0" and it increases till 9 before going back to 0.It's good enough for me though as a test.

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Hi,
I'm working on the project as well
what was the distance between the emitter and receiver?
did you use A0 or A3 as the analog input?
I just get " Start of the receiver program"
and nothin else.
any suggestions based on your experiences?

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Sorry for the late reply.I used A0 as recommended.I forgot to add that I already swapped the red LEDs with clear blue LEDs instead as recommended too. The distance I tested with blue was around 5cm(clear red should give better distance).Before I just used 1 Mohm resistor for the receiver,100ohm resistor on the transmitter and only received garbage bits but after I attached another 220ohm resistor on the receiver,I started to receive the msg "Hello World" followed by 0 till 9 in loop.

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Thanks for the reply!
Sure it's A0 and not A3?
cuz both are mentioned in the explanation
and did you use the 220 ohm in series to 1Mohm or parallel.
which pin did you use at the transmitter 13 or 2?

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Yup it's attached to A0.I put the 220 ohm parallel to the 1Mohm.For transmitter I used pin 2.

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hi, may i see your hardware circuit?

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Hello imayyami,
did you find circuit diagram?if yes,please do share it

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