ZX-Spectrum +3 Casette unit

To connect the casette unit to the ZX-Spectrum +3 you need the following connector.

                                               To EAR socket on casette unit
                         Input                                 ___
|<- ZX Spectrum +3 ->|   (EAR)                             __ /   |____
                           |                              / _|    |____()
                           |       ___                   / /  \___|
             ___    _      v      |   --_               / /
 Input (EAR)    \/ | |     _ _____|      -.------------' /
                   | |  ()[_[_____|       |-------------<
Output (MIC) _/\   |_|  ^       | |     _-^------------. \  
                    |   |       | |___--                \ \    ___
GND (common) _______|   |       |                        \ \_ /   |____
                      Output   GND                        \__|    |____()
                       (MIC) (common)                         \___|

                                               To MIC socket on casette unit   

Notice that the jack plug on the ZX Spectrum's side has 3 seperate metal section.