Is it mandatory to send 0.001434 BTC to the adress above in order to get the free blackbyte ?
I don't have any bitcoin balance nor any bitcoin wallet.
Thanks
No you need to sign the address which while it will not require a bitcoin balance it will require a wallet.
Good Luck.
I recommend to install Electrum (for desktop) or Mycelium (for Android) to do this. Both support signing messages and like wry wrote, you don't have to own any Bitcoins for that.