I just bought Arduino Uno and HC-06, I hooked up the connections:

  • 5V Bluetooth → 5V Arduino
  • GND Bluetooth → GND Arduino
  • TDX Bluetooth → RX →1
  • RDX bluetooth → TX → 0

Here are the pictures:

HC-06 Arduino

My problem is that I cannot seem to search for the Bluetooth connection on my Laptop or on my phone. Is there something wrong I am doing here?


1 Answer 1


The R and T in "Rx" and "Tx" stand for "Receiver" and "Transmitter".

So the Transmitter from one device should be connected to the receiver of the other device. Thus:

  1. Arduino Uno Rx -> HC-06 Tx
  2. Arduino Uno Tx -> HC-06 Rx


Thanks to the pictures that I can now see, what are the values of the resistors on the Arduino Tx pin? 2.2k I think, but I cannot see very well.

In idle mode, both Tx and Rx should be high (5V). Can you verify this with a multimeter? This pdf (p.8) states that the Rx should be pulled high. I assume that is what you did with the resistors, but I am confused to why you have two resistors. Could you explain this please? Usually a simple 10k resistor to Vcc should be sufficient. Adding a resistor between the Arduino Tx and the cable will cause reflections because of the impedance change and affect the signal quality.

  • $\begingroup$ Sorry about the typo, bluetooth is properly connected to the arduino in the picture $\endgroup$
    – user4013
    Commented Mar 10, 2014 at 19:28
  • $\begingroup$ I can't seem to find any bluetooth connection from my phone when i scan $\endgroup$
    – user4013
    Commented Mar 11, 2014 at 3:19

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