APC220 with Arduino - Don't work - No connection!

I'm trying to achieve connection between my Arduino UNO and my set of APC 220. I have done EVERYTHING as it had to be, I connected the APC220 Tx to Rx and Rx to Tx, I have made all the appropriate settings in RFMAGIC software to set the rate, the Mhz etc but NOTHING. I'm going mad, I can not understand what is happening. It's been 3 days I have checked everything but when I open the Serial Monitor of Arduino IDE it shows nothing (I have made a test "Hello world" program) and no led is blinking on Arduino. I tried several frequencies, tried different or same NODE IDs, but nothing.. Please help if anyone knows

I also saw many topics on this forum about my APC220 problem and no one of them helped as no one achieve to find a solution!