Set up a Baofeng UV-5R Repeater System

Set up a Baofeng UV-5R Repeater System

Instructions on how to set up / build a Baofeng UV-5R VHF Repeater System or use Baofeng as repeater. This setup could be used or deployed in emergency or disaster, SHTF or WROL situations where communications are vital for survival. Instructions presented in this video are for educational purposes only. Pardon for the grammatical and pronunciation errors; English is not my mother tongue.

Check it in action *
http://www.youtube.com/watch?v=_KrH86...

What you need:
The Baofeng repeater system is composed of an RX (receiving) unit and a TX (transmitting) unit so that means you'll need 2 Baofeng UV-5R radios. No need for radio tone controller. The setup takes advantage of the VOX feature (Voice Operated Transmission) on the TX unit. Aside from the RX and TX units, you will also need a stereo cable with 3.5mm Male and 2.5mm Male ends just like this:

http://dx.com/p/3-5mm-male-to-2-5mm-m...

Other notes:
Frequencies have to be dialed in on the repeater system and the radios which will be used to communicate with the system. In the video, I used 2 UV-5Rs to communicate with the repeater system but you can also use other 2-meter portables as long as it can do frequency shift and you can specify the shift direction. It could be any brand-model portable transceiver and not necessarily a Baofeng UV-5R.

* Drawback
Though not evident in the video due to close proximity of the test radio units to the repeater system, there is that so-called 'receiver desensitization' (a.k.a desense) which can be "defined as on-channel noise or a strong off-channel signal that degrades the receiver sensitivity. On-channel noise can be coming from the repeater or passing through the duplexer from some other source. An off-channel signal can be close in frequency and physically located somewhere else (another site), or it can be located in close physical proximity to the receiver, but not necessarily close in frequency. Either situation will restrict the receiver's capability to detect (pick up) a weak signal, such as a low-level signal from a mobile or handheld radio."
http://www.bird-technologies.com/Reso...


Solutions:
1. Vertical and horizontal space separation/ isolation of the TX and RX antenna

2. Install a duplexer tuned to your desired RX and TX frequencies; enables you to use only one antenna for the entire repeater system setup (connected to the duplexer).
http://www.youtube.com/watch?v=uNf4u-...

3. Crossband repeat with 150 plus MHz separation. Receive on UHF then transmit on VHF, separate TX and RX antenna, no duplexer.
http://www.youtube.com/watch?v=nfAe65...


I hope this helps. Thanks a lot for watching. Maraming salamat po at Maligayang Pasko sa inyong lahat.