Abstract: A portable cable tester is used to test electrical cables between transformers of an electrical power distribution system. The cable tester has a cylindrical housing with an elongated electrically conductive prod at one end for insertion into a receptacle connected to one conductor of the cable. The second end of the housing has an on/off switch, a second terminal, and an annunciator, which is preferably in the form of spark gap electrodes. The cable tester includes a capacitor (or capacitors) connected between the first and second terminals and charging circuitry for charging the capacitor. In use, the elongated prod is inserted into the receptacle connected to the one conductor, and the second terminal is connected to the other conductor of the cable. The on/off switch is turned on, and charging of the capacitor or capacitors is commenced. When the voltage across the capacitor attains a threshhold value, the annunciator is actuated.