[Amps] New Design Question

[TexasRF at aol.com]

Before I run off to invent a new square wheel, here is a question for the  
group:
 
I want to tune up a new cathode input circuit for a 222 MHz amplifier using 
 a GS23B tetrode (I have some already). I am wondering if for tuning and 
test  purposes, could the cathode input impedance be simulated by removing the 
grid  bias and all other voltages except filament and driving the input 
with low power  rf.
 
It seems that 50 ohms, for an example, could be simulated with say 10 mW  
(+10 dBm) and tweaking the circuit for a grid current of 14 mA at resonance. 
 
The thinking is that at 50 ohms, there will be .707 volts rms with 10 mW of 
 power and the current would be 14.4 mA due to this 
power/voltage/resistance  value. The tube can handle 25mA CCS so 14.4 mA is no strain.
 
Why do this? Because of the difficulty of connecting a substitute  
termination resistor with the needed very short leads at this frequency and it  
would be so easy to do.
 
Any comments and criticism will be cheerfully accepted. I don't mind  
octagonal wheels so much, just don't want square ones!
 
73,
Gerald K5GW