This switch box is the product of much effort in talking a manufacturer into making one to our specification. It is designed to go at the rear of a vehicle and change channels using the reversing light positive as the trigger. It is important as it will allow and existing single cable to be used with out twin lens camera. It will also mean a twin lens camera can be used as a wireless camera without the extra expense of needing 2 transmitters and receivers. The switch box takes its power from the 4 pin camera feed, but needs a wire to the positive of the reversing light to switch channels.
This box has been used by people to install a twin lens camera on a caravan with a single wireless transmitter and receiver. It saves cost as previously to do this a transmitter and receiver was needed for each lens of the camera. It has also proved very useful when you want to install a twin lens camera on a vehicle with a pre-fitted single cable. It avoids any cross-talk between channels you can get by using splitter cables.
The diagram above shows how it is wired in (if you right click and open in a new tab you will get a full size version). It can be used directly into a single 4 pin aviation style connector. Some motorhomes are fitted with a PS/2 style cable. Many UK built vehicles and older continental vehicles will commonly use this connector. With this style of cable occasionally not all 6 pins are connected. The older the motorhome the more likely this is the case. It is advisable to do a continuity check along the cable if possible. More recent continental vehicles are likely to have the modern Waeco style connector. We have adaptors to match both of these connectors in stock.
When the switch operates it only uses one channel on your monitor. If your monitors switches to AV2 when you go into reverse then that is the channel to use. If you cannot manually turn your monitor on when not in reverse then you will need to switch the green (usually) reverse light trigger wire to an ignition live power supply (that is quite unusual though).