Some of the older tube transmitters were more prone to
TVI, since the manufacturers didn't bother with TVI
filters since there were not many televisions around to
bother! By the time you get to the gear made in the
60s (SB series, DX-60, etc.) the transmitters usually
included a multisection 30 MHz lowpass filter on the
output. Transmitter shielding is also important.

Pete