Authored by VE3EFJ
6.1.1 T-4 Evolution
The T-4X and the T-4B differ very little, except mostly in the PTO dial plates. The T-4C functionally was not much different from the T-4B, except in areas of operator convenience. The T-4C is noted for the following major differences:
 | Separate BFO Line |
| FETs in the BFO oscillator |
| Different method of ALC detection |
| VOX on/off from front panel |
| Controls moved to back of set |
| Dual concentric PTO dial plates |
| Plain chassis |
| Meter switch activated by pushing LOAD control shaft |
| Active PTO indication by dial light |
| Blank RCA jack holes for VHF transverter drive kit |
| Separate VOX delay controls for SSB and CW |
