RE: 9C Synth module
Hi Norm,
Yes, the 9C Synth module will work in the 8U and 7U series radios.
I hope you find this information helpful. You can also reach our Futaba support technical team at 217-398-8970, or via fax at 217-398-7721.
Sincerely,
Krysta
Lead Futaba Customer Service and Programming Technician