I bought a 433MHz xmtr/rcvr and I'm trying to match an antenna to it. I know I could use a 1/4wave wire, but I have a Nano VNA and I'd like to try and tune the antenna. The manufacturer does not specify the output impedance, but if I sum the two inductors in the VCC path, as shown in the attached image, I calculate the output impedance to be about 20k ohms. That's assuming the total inductance is about 700nH. Does that sound right?