The Ameritron ARF-500K2 is a filtering circuit that allows the ALS-500M to be used with the ALS-500RC (remote head).
This is for the older ALS-500 units
The ALS-500 Remote Head allows the amplifier to be placed away from the operating station and still have access of the front panel controls. The Remote Head has a Frequency Select Switch, ON/OFF Switch, Relay control jack, Current Meter, and three LEDs for TX, O/L and Power.
The ALS-500M will still have front panel controls (ON/OFF, Frequency Select, and Thermal overload, Load fault indicators), along with remote capability after the new filter circuit is installed.
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