It doesn't recognized Tiny RTC I2C DS1307 (with ARduinoUNO)

Using Arduino Project Guidance
#1

I was trying to set the time in my new Tiny RTC but it doesn't work.
The last code I proved is this one:

The monitor says:
The current date and time is: 165, 20165 153:165 PM

I believed that the direction in the code wasn't the right one, so I decided to try out this code to see which one is the correct:
http://playground.arduino.cc/Main/I2cScanner
As a result I get: "No I2C devices found"
Why it doesn't recognized the device?
I am using Arduino UNO and Tiny RTC I2C DS1307
I have made the conections as this:
https://www.google.es/search?q=conectar+tiny+rtc+ds1307+arduino+uno&es_sm=122&source=lnms&tbm=isch&sa=X&ei=jO19U4S8BYGu0QX8-oDoBw&ved=0CAgQ_AUoAQ&biw=1536&bih=747#facrc=&imgdii=&imgrc=Ysy14Fntf2PwoM%253A%3B1RxD1dEqGnFckM%3Bhttp%253A%252F%252Fzygzax.com%252Fwp-content%252Fuploads%252F2013%252F04%252FDSC_0061-1024x768.jpg%3Bhttp%253A%252F%252Fzygzax.com%252F2013%252F04%252F22%252Freloj-con-arduino-y-el-modulo-tiny-rtc-i2c%252F%3B1024%3B768

Can anybody help me out?

#2

How do you power your setup? Just by USB? The DS1307 is quite picky about the voltage of the supply power, especially if the module has a fresh backup battery. If the voltage drops below 1.25 times the battery voltage the module stops talking to the MCU. Fresh batteries often provide a voltage of 3.5 to almost 4V. If your USB voltage drops a little bit below 5V (which is often the case) you cannot communicate with the DS1307.

#3

To set the time I conect Arduino to the PC by USB and I put the battery in the RTC. I've got more or less 6V of supply with the Arduino (I don't know why if it is said to be 5V) and 4.48 V in the battery, so at first it doesn't seemed to be the problem.
I don't know...

#4

Are you sure your multimeter is measuring correctly? I think both values are relevantly bigger than usual. Try powering the Arduino with a 9V power supply.

#5

Thank you for your answers.

.. I'm interested in the combination Arduino UNO + Tiny RTC so I only have 5 V to supply the RTC.

What I need is a the REAL time. I have just recieved the Ethernet Shield, could I conect to a server and take the real time? How can I do that?

#6

First off, replace the battery in your multimeter. If it reads too high (like it does now)

Second, in Arduino Examples → Ethernet there is a NTP-example thar retrieves the time over the internet, and writes it to the serial terminal. You could easily change the code to suit your needs.

// Per.

#7