powering simple circuitry in rudimentary lighting desks. Pinouts vary between manufacturers: Zero 88, Anytronics, Lightprocessor and Strand have the control signals on pins 1–6, 0V on pin 8 and power on pin 7 and Pulsar and Clay Paky have power on pin 1, 0V on pin 2 and channel outputs on pins 3 to 8. The polarity of the power supply and control signals relative to ground also varies, with Strand having negative voltages, but most other brands having positive voltages. Other designs A polarised two-pin unshielded connector, designed for connecting a loudspeaker to a power amplifier (or other device; many of the earlier shoebox style tape recorders used them), is known as the DIN 41529 loudspeaker connector. It commonly exists as a panel-mounting female version, and line-mounted male and female versions, although there were rare panel mounted male connectors, for example fitted on the external speaker boxes on certain early 1980's Luxor TV sets. The male version has a central flat pin, and circular pin mounted off-centre. The circular pin is connected to the positive line (red) while the spade is connected to the negative line (black). The panel-mounting female version is available with or without an auxiliary contact that disconnects the internal speaker of the device if an external speaker connector is inserted. Most common is a three-hole female connector with one circular hole on either side of the spade hole, one of them with an aux contact and one without, which provides the option to leave the internal speaker connected by inserting the plug twisted by 180°. Many European car radio/stereo brands used this connector, commonly spaced so close apart that you need smaller male cable connectors. This was commonly used in conjunction with a connector block with two larger and four smaller flat blade connectors with a standardized pinout for power in (main power, memory for radios with electronic settings memory, dahslight power) and out (for an automatic electric antenna). This setup was commonly combined with an 8-pin DIN connector where pin 1-5 were used for line output for connecting power amplifier (using the same pinout as for home audio equipment, except "tape record" would be front audio out and "tape play" would be rear audio out). The middle pin was used for remote start of an amplifier. If standard 5-pin home audio cables were used the automatic antenna connector could also be used for remote