For an ideal transistor, the reverse parameters (h_o & h_r) are

• Every linear circuit having input and output can be analyzed as a two-port network.
• In these networks, there are four parameters called hybrid or h-parameter. Out of these four parameters, one is measured in ohm, one in mho, and the other two are dimensionless. Since these parameters have mixed dimensions, so they are called hybrid parameters.

h_i = input resistance with output shorted (Ω)

hr = Reverse voltage gain with input open (V)

hf = Forward current gain with output shorted

ho = Output conductance with input open

Ideally, hi & h_o have a value of 0.