2:1 Combiner

Hello,



If I Connect Cable A to Port #1, Cable B to Port IN, and 50Ω termination to Port #2.
Would I still lose 3dB on the Combiner, between Port #1 (Cable A) and Port IN (Cable B)?
Would I get any refelction from the 50ohm termination which might affect the signal that passes from Cable A to B?

Thank you.

That still holds true yes.

you won't get reflections because port 2 is properly terminated, but you will still get the 3db insertion loss because the signal is being split between whatever device is connected to port 1 and the 50 ohm dummy load on port 2.

reflections are a result of impedance mismatches, and with the 50 ohm load on port 2, the port is properly matched and should not cause reflections. all of the power on port 2 is absorbed by the terminating resistor. in your original thread, you wanted to connect two radios for different frequency ranges to these ports. the radios will cause reflections with out of band signals, because their 50 ohm input impedance is only valid for the band they operate in, and would not be 50 ohms for signals outside their range.