You could also splice a switch onto the red receiver wire as it is required for the BEC to supply power to the receiver. This switch on the red wire could serve a dual purpose; if you ever use a UBEC you could have the switch turned off without needing to take out the red receiver wire.
Just make sure that if you do use a switch that you still unplug the batteries. The 9920's circuitry will still draw a small current even when it's not receiving a signal.
SH Z-Car, Custom Crawler, 8s Savage, 12s XTM XLB 1/7 buggy, 4wd 4-link rear/IFS Pro4 truck, Custom Hyper 10 Short Course, Belt-Drive Mammoth ST 1/8 truggy, 4s 17.5 MM Pro HPI Blitz
I had a switch wired on the red wire on the ubec...but prefer to wire in a switch on the black and red (correct) wire sequence. the other way fried my ubec....
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