[Station X]

The set should work with the battery connected either way round. It was not intended for use in a vehicle, but were it used in this way, deriving its power from the vehicle's battery, it would be prudent for the polarity of the radio's chassis, which is connected to the earth terminal, to match that of the vehicle's chassis.

First step in investigating the lack of sound should be to check for HT voltage. If there is none check for AC on the primary and secondary windings of the step up transformer.