Hello,
We plan to use LMX2492EVM to test some RF transmit and receiver. As shown on the Figure, an antenna is connected on RFOut/2 as transmitter and an antenna on RFOUT as receiver. R6 was removed so the receiving signal on RFOut go to Fin* on pin 5 of the PLL (U1). The surprise is that the lock indicator (from MuxOut and a LED on the second page of the schematics) is always ON, even when the receiving antenna at RFOut was removed. Does anyone know why the PLL is always locked ? Is the RF signal coupled into the PLL's Fin* pin ? Our RFOut/2 is set to 4.8GHz.
Many thanks in advance.
-Charlie
https://www.ti.com/lit/pdf/snau160 (user manual)
