Can an automatic antenna tuner be safely used with all low-power rigs?
The vast majority of commercial, kit, and home-built transmitters have some form of protection from high SWR. This is important when using either a manual or automatic antenna tuner, because a wide range of impedances is presented to the final stage during tuning. SWR protection is often mentioned in the specifications or theory of operation section of a transceiver manual. If not, take a look at the schematic. If the transmitter includes ALC, current limiting, or voltage limiting (i.e., a zener diode at the PA collector), chances are it can be used at full power during auto-tuning. If youre not sure, do auto-tuning using no more than half the rigs maximum power output. Small transceivers of many types have been extensively tested at full power with the T1.
