SL-8 and the F-14 Tx

[mickelsen]

Will the SL-8 receiver work with the Futaba F-14 transmitter? They say it will work with non-Futaba receivers but then it has all those add-on modules that have to be controlled some way. I don't know how they do that, but I wonder if you need a special receiver for it. Can you explain this?
Thanks

[KevinMc]

Hi Mark,

The SL8 works just fine with the basic F14 although I've not been able to get my channel expander to work with it. The channel expander plugs in like a secondary receiver, but because it is driven by a seperate encoder in the transmitter I think the built in DSP functionality of the SL8 may be "stomping" on that part of the signal. I wonder if turning off the DSP funtion on the SL8 may enable it to work but I've not yet tried that out.

Aroosh?

KMc

[sombra]

The channel expander will not work with the SL-8 as the DSP fucntionality of the SL-8 will not let the stream through. You can try to gang two SL-8s to control more than 8-channels and see if that works, unfortunately, I don't have the F-14 so can't say definitely if it will work.

Hi Mark,

The SL8 works just fine with the basic F14 although I've not been able to get my channel expander to work with it. The channel expander plugs in like a secondary receiver, but because it is driven by a seperate encoder in the transmitter I think the built in DSP functionality of the SL8 may be "stomping" on that part of the signal. I wonder if turning off the DSP funtion on the SL8 may enable it to work but I've not yet tried that out.

Aroosh?

KMc

[KevinMc]

Hi Aroosh,

Two paralleled SL8s would not be compatible with a channel expanded F-14. With the channel expander in place the encoded pulse stream emitted by the transmitter is still only 7 pulses per frame, the expander just time(frame)-division-multiplexes one of the last three channels. From comments I've seen other places about having to turn off the DSP function to get a buddy-box to work, I'd anticipated that a similar approach may allow the expander to work but I've never sat down to try it out.

Knowing that the channel expander works on a frame-multiplexing scheme instead of increasing the total encoded channel count do you think turning off the DSP may allow the expander to work?

KMc

[sombra]

If it is time division multiplexing, then it may work. Without looking at the capture of the PPM frame can't tell certainly... Turning off the DSP and trying it out is probably the fastest way to find out :)

Hi Aroosh,

Two paralleled SL8s would not be compatible with a channel expanded F-14. With the channel expander in place the encoded pulse stream emitted by the transmitter is still only 7 pulses per frame, the expander just time(frame)-division-multiplexes one of the last three channels. From comments I've seen other places about having to turn off the DSP function to get a buddy-box to work, I'd anticipated that a similar approach may allow the expander to work but I've never sat down to try it out.

Knowing that the channel expander works on a frame-multiplexing scheme instead of increasing the total encoded channel count do you think turning off the DSP may allow the expander to work?

KMc

[mickelsen]

I'm very interested in this discussion because I have my own plan about multiplexing data onto one channel of the F14. The F14 has signals available to help with the synchronization of the data with the data frame. I figure that, with a microprocessor controlling the input to that channel and another decoding the output from the receiver, I should be able the send a lot of specialized control information to my sub. But if the Sombra filters that type of thing out of the data stream, then I'm out of luck.
I have no idea how the disable the DSP function on the SL-8. Can you tell me how? And if it is disabled, doesn't that compromise the performance of all the channels?

Thanks again.

[sombra]

The DSP can be turned off by dialing 95 on the programmer. In the presence of excessive noise and interference the performance of the SL-8 is definitely better with DSP turned ON, however, with DSP turned off the SL-8 is no worse than your Futaba receiver.

I'm very interested in this discussion because I have my own plan about multiplexing data onto one channel of the F14. The F14 has signals available to help with the synchronization of the data with the data frame. I figure that, with a microprocessor controlling the input to that channel and another decoding the output from the receiver, I should be able the send a lot of specialized control information to my sub. But if the Sombra filters that type of thing out of the data stream, then I'm out of luck.
I have no idea how the disable the DSP function on the SL-8. Can you tell me how? And if it is disabled, doesn't that compromise the performance of all the channels?

Thanks again.