Traffic with ADS-B in

Just wondering, with only ADS-B in (dual frequency), would I see only the traffic that has ADS-B out or all traffic that is in the system (those also with only transponders)

Thanks in advance

Complicated

You'll pick up direct signals from other aircraft broadcasting with a mode S. The ground stations will not send you traffic (uplink) since they do not know you're there, since you have no ADSB-out. But if there's a nearby aircraft with ADSB-out then you'll piggy back on the uplink intended for him, and get traffic.