upgrading multiplex picoline

The Multiplex Picoline is a 7 channel transmitter. To enable the use of channels 5 ... 7 and enable mixing ratios you need to either buy the upgrades from a Multiplex dealer or make them yourself. In essence they are just potentiometers (4.7 kOhm if I remember correctly) and switches. To see how to connect the potentiometer to the transmitter board, have a look at how the stick potentiometers are connected. Another upgrade is the channel check, which checks that the channel you are using is clear when you turn on your transmitter.