Matt, the DX7 is a great gift! What you need is a JR stereo-to-mono adapter to work with the DX7. Are you using the Ikarus y-adapter with your 9C? That adapter has a JR adapter built in, so you can use that. Otherwise, you'll have to get the y-adapter from Ikarus USA http://www.ikarus-modellbau.de/onlin...ca088.63839801 or the one from FXA http://www.fxaeromodels.com/product_...3394b887d3efa7 Put the DX7 into airplane mode, and switch it off. The Tx should turn on automatically when you plug in the JR adapter, and disable the RF transmission. For peace of mind, you might want to remove the module.