Tethering RRC3 to RTx

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Active Member
Jul 4, 2016
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I am having difficulty hooking my RRC3 (v1.60) up to my new RTx. I have verified DIP switch settings and RRC3 telemetry settings...and both the RTx and RRC3 work fine independently. The RTx user manual says in bold letters:

When tethering to an RRC3, turn on the ROCKET unit wait for no-sync tone, then boot up the RRC3.

What is "no-sync tone"? The only time when there is no tone - is after the RTx power up and before it gives code 9 and/or the RRC3 starts beeping a code.

When I power up the Rocket unit (tethered through Comm), the LED on the RRC3 flashes, but there is no tone, until I power it up. Also, I don't believe that I have been able to boot up the RRC3 without a fault code once the Rocket unit was already powered up.

Any help is greatly appreciated.
The rrc3 needs to have the uplink set to 1 htz by using the mdac program. I believe the default is 0.5 htz.
Yes that is the correct option.

I turn on the RTx in the rocket, then wait until it starts beeping, turn on the RRC3 and the base unit.

If you still have trouble, email Jim. He has always been very helpful.