JFET Parameters (PCB marked BF545A but 2N5457 installed)
Q1
Vgs(off)=-0.42V at Id=5.4µA
Vgs(on)=0.14V at Id=5.00mA
gfs=20.9mA/V at Id=3.0mA to 5.0mA
Idss=2.23mA at Vds=3.00V
Rds(on)=31.9Ω at Id=5.0mA and Vgs=0.0V
Q2
Vgs(off)=-0.31V at Id=5.2µA
Vgs(on)=0.24V at Id=5.00mA
gfs=21.9mA/V at Id=3.0mA to 5.0mA
Idss=0.90mA at Vds=3.01V
Rds(on)=37.2Ω at Id=5.0mA and Vgs=0.0V
Q3
Vgs(off)=-0.30V at Id=5.3µA
Vgs(on)=0.24V at Id=5.00mA
gfs=20.8mA/V at Id=3.0mA to 5.0mA
Idss=0.87mA at Vds=2.99V
Rds(on)=37.4Ω at Id=5.0mA and Vgs=0.0V