[TenTec] Question about 301 encoder

[Ben K8DIT]

The 301 is just an optical encoder and all it did was serve as an external
tuning knob with the Omni V and VI and VIplus. The RS 232 on the rear panel
provided the interface for this accessory.  There is no other feature aside
from band/mode/time info for logging provided for thru this interface.
No other previous models had remote tuning knobs such as this, but all
successive models have been accessorized with remote tuning plus some
transciever controls, relative to whose firmware/software is used.