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Detail of the aft VHF in-flight antenna (used to communicate with the command module). I have additional pictures of the forward VHF in-flight antenna.

As described by the Lunar Module News Reference,

The two VHF in-flight antennas are omni-directional, right-hand, circularly polarized antennas that operate at 259.7 and 296.8 mHz.

Picture 1 of 2.

Also visible here at left is the cone-shaped VHF EVA antenna.