Q6, and maybe R42, possibly the crystal filter, but the transistor going bad would likely have kept too much signal from going there for very long. it's a terrible copy of the schematic, a lot of lines don't show up. the only way i knew Q6 was the receiver front-end was the 220Mhz crystal filter.
strange comment ... actually the schematic is perfect
easy to read maybe update your PDF reader
But I agree about the diodes and also include D1 in that list so D's 1,7,8,13 they are all likely to RF switching PIN diodes
here's the description of the TX/RX switching....
TRANSMIT/RECEIVE SWITCH
When the radio is in the transmit mode, pin diode switches D13 and D1 are both turned on (representing less than 0.7 ohms). D13 allows the transmit
signal to pass to the antenna and D1 shorts one leg of a T matching network (L3, L15 and C4) to ground in the receive path. This results in a parallel tuned
circuit high impedance being presented to the transmit signal so that the receive path does not load the transmit signal. In the receive mode, both D13
and D1 are off, resulting in the antenna signal being coupled into the receive LNA through the 50 ohm T matching network and the unwanted load of the
transmit final amplifier is reduced to less than 1 pF by D1.
Dave