It's an experimental satellite, it's downlinking data rather than just being a bent-pipe relay. This is right before SGLS and the mass adoption of S-band (USB)

It's an experimental satellite, it's downlinking data rather than just being a bent-pipe relay. This is right before SGLS and the mass adoption of S-band (USB) so it's going to likely be a basic VHF BPSK kind of signal. This is also before encryption was easy so it's likely going to be in the clear.