In the newer version of OpenTX, a new dialog box has been added when you try to bind a Frsky receiver to your Taranis. There are four options, “Channel 1-8 or 9-16, and Telemetry On or Off. This article will explain what these options mean.
If you are flying a mini quad, 99.9% of the times you will be using “Channel 1-8, Telemetry On“.
But if you want to know what the other options mean, take a look at this article.
By selecting “Telemetry ON/OFF”, is going to determine whether telemetry is enabled or disabled for this receiver.
For telemetry to work, there is a small transmitter on the radio receiver to send data back to the radio transmitter.
There are situations where you might want to control multiple radio receivers at the same time, for example when you use receiver redundancy feature.
We talked about receiver redundancy when we were reviewing the R-XSR. It basically allows you to connect a secondary receiver to a primary receiver, and in case of radio signal is lost with the primary receiver, the system could fall back to the secondary receiver.
However, you can’t have both receivers sending telemetry data back at the same time, because our radio transmitter can only listen to one receiver. Therefore you have to disable telemetry for the secondary receiver in this case. Telemetry is only enabled for the primary receiver when binding.
That’s what the Telemetry On and Off options are for.
If you are not using the receiver redundancy feature, just bind with telemetry on regardless what receiver you use. Even though for RX’s that don’t support Telemetry such as the XM and XM+, it won’t really matter.
It’s true that by using 8 channels instead of 16 reduces latency. But this is not how to select 8 channels. You select 8 channels under “Channel Range” in model setup.
So what’s “Channel 1-8 and Channel 9-16”?
Basically the option Channel 9-16 is for people who use receivers that has PWM outputs for things like servos. And Channel 9 to 16 will be the PWM signals coming out of that receiver.
For an RC plane with complex control, where you need more than 8 channel, you can use 2 receivers at the same time. Use the first receiver for the first 8 channels as well as telemetry, and use the second receivers for channel 9-16 and output PWM (such as the X8R receiver) for controlling servo, camera gimbals, FPV switcher etc, without telemetry.
On some receivers, RSSI comes out of Channel 16. By selecting channel 1-8 won’t affect RSSI, it will still come out of that channel.