DCARA has 3 sites that all share a common control radio frequency. This allows us to link some repeaters in half-duplex, as the control link radios are a single Motorola CDM1550.
All control radios operate on the same frequency, so linking a repeater to a control radio can be thought of as adding it to a group or pool.
To link and unlink certain repeaters, it is important to understand how these sites are internally configured.
|1 (92)||2 (N/C)||3 (Link)|
|A||Link/Unlink 92 & Control Radio|
The 146.92 site is the most simple of the bunch. Linking or unlinking the 92 and Control Radio simply routes audio from the 92 receiver to the Control Radio transmitter, and from the Control Radio receiver to the 92 transmitter.
|1 (17)||2 (050)||3 (Link)|
|3 (Link)||X, A, C||X, B, C|
|A||Link/Unlink 17 & Control Radio|
|B||Link/Unlink 050 & Control Radio|
|C||EOC Hot Standby|
|D||Link/Unlink 17 & 050|
The EOC site is slightly more complicated than the other DCARA sites. In a default state, the Control Radio receiver is linked to the 17 and 050 transmitters to allow NOAA audio from the 146.92 site to be multicasted across these repeaters.
Linking Example (link 17 and 92 repeater):
Unlinking Example (unlink 17 and 92 repeater):