The Wireless Set 19 uses a separate power supply, this allowed the power supply to be replaced quickly, if it became faulty or required a service.

There are three types of power supply that were used by the Wireless Set 19, these were:

Power Supply No 1: First version of the power supply, manufactured by the British, Canadian's and the USA. Used a single large Dynamotor to provide HT1 and HT2 for the radio. Offered poor battery usage, when a station was dismounted and powered from a signals battery, as the dynamotor was constantly rotating at full speed. Generally this model of power supply was used with the Mk2 19 set, noted by the 6 pin output socket, the same as the 6 pin input socket on the radio. The USA only manufactured this model No 1 power supply.

Note: If purchasing a USA produced No 1 power supply, the US did not have switches that were meant to fit the power supply design, so they produced the front panels to take the large British switch with four mounting holes, expecting the correct switches to be available by the time production started. They did not receive the switches, so fitted a round type switch available in the USA and rounded out the slot for the intended switch to take the one they could source. So if you spot this, they are all like it from the factory, it is not a later modification.

Power Supply No 2: This version came along after the No 1 power supply, it was designed and produced by the Canadian's only and incorporated improvements based on their field experiences. The main improvement was to provide a vibrator circuit to power HT1, so when the station was on receive only, the power consumption is greatly reduced, extending battery life when running on a signals battery. This version was commonly modified when they were on the surplus market, to provide mains power for appliances in a motor vehicle. The No 2 power supply generally powered the Mk 3 radio and has a 12 pin output socket, the same as the 12 pin input socket on the Mk 3 radio.

Power Supply No 3: This was the British power supply that replaced the No 1 power supply for use primarily with the Mk 3 19 set. The power supply has a 12 pin output socket the same as the 12 pin input socket on the Mk 3 radio. The design is simpler than the No 1 and the main change is two small dynamotor's are provided to supply HT1 and HT2 independently. This reduced the power consumption when on receive, extending the battery life when running on a signals battery. With a simpler layout internally servicing was easier than the No 1.

Note: The main reliability issue with the No 3 power supply is the on / off switch, they are of a poor design and are commonly worn out, when using this version, when turning on, attention should be paid to check the LT has come on, if it doesn't but the HT does, it is normally a faulty switch.