Can you measure the plug end and tell me the pin spacing, it will either be 2.5mm (0.1" or 2mm. I suspect its 2.5mm. To confirm, WITH THE BATTERIES REMOVED!, will the plug fit any of the TK-13RX# sockets?
Simon,
It looks as though the pin holes are 2mm apart, rather than 2.5mm. The emitter plug will not fit into the TK-13RX board and it is clearly smaller than a Hen Long plug, as well. Maybe you can tell something from these pictures. [

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