The link below is to data on the FLARM antenna at 916 MHZ. *I have a good
source for those antennas. *The ADS-B antenna is shorter and for 1090MHZ.
Those are the ones I can't find.

The two antennas supplied with my brick are 98mm long. The only
difference between them is that one is SMA and the other RP-SMA. Both
of these antenna are shown on the data sheet referenced.

Are you saying that some people were provided, or are being provided,
with a different ADS-B antenna?

If so, could this have any bearing on the unsatisfactory PCAS
performance reported by some owners?

Andy