首页>
外国专利>
Traffic light, in which dc signals of a geberort by means of which is provided on both sides with insulating to the transmission lines and transmitted as pulses of alternating polarity at the reception site be taken up by means of a polarized relay
Traffic light, in which dc signals of a geberort by means of which is provided on both sides with insulating to the transmission lines and transmitted as pulses of alternating polarity at the reception site be taken up by means of a polarized relay