A digital signal processing vestigial-sideband television modulator receives a television signal. The halophthalic acid may be dehydrated to form halophthalic anhydride which is useful in the synthesis of polyetherimide. At least one message is transmitted to at least one hydrogen generating device for activation, deactivation, or decentralized hydrogen storage management, and at least one response is received from the hydrogen generating device for regulating hydrogen production.