[TenTec] 229A SWR Circuit

[Stuart Rohre]

Rick,
The most likely failures of any SWR measuring circuit are 1) short of 
open of diodes
2) changes in carbon resistor values
3) Someone messing with, or a bad calibration pot
4) Finally, capacitors even disk ceramics commonly found, can go bad if 
ever the unit took a current surge.

Check those in 1-4 order, and likely you will find something.

GL,
Stuart Rohre
K5KVH