Can a servo range be set to greater than 125%?

[kokopeli]

I would like to drive the servo on my sailboat way out of the normal range.
The servo has been modified to accept a wide swing, however the signal to the servo must be way out of the 1 to 2 ms that is normal.
the 125% value that seems to be the max for er9x firmware is not enough.
Thanks,
Walt

[Kilrah]

125% on er9x is already significantly more than what commercial radios will allow.

You might want to either modify the servo itself (add resistors inline with the "end" connections of the potentiometer), or use a servo stretcher (commonly used in FPV applications, a little device that plugs between receiver and servo and doubles the pulse excursions).
Be careful not to overdrive and break the pot though. These cover about 180°-270° max depending on the servo. For any more throw will need you to take the pot out and connect it for example through a reducing gear.

[kokopeli]

Thanks for the quick reply.
I was afraid of that.
Yes, I understand that physical limits of the servo and that has been accounted for.
I guess I will have to ask for that feature to be added to the firmware, eh?
I was in hopes that someone would tell me that I could mix something with it to make it a wider range.

Walt

[gohsthb]

Have you ever seen or heard of another Tx system that allows this? It seems to really violate the standard.
-Gohst

[kokopeli]

No I haven't heard of one.
My DX6i goes to 125%.
Of course I expect the 9x nonstandard firmware to give me nonstandard results. LOL
Seems like a pulse strecher is a good canidate for the firmware.
Thanks anyway.

Walt

[gohsthb]

FYI 125% on a DX6i is probably the same as 110% on Er9x.
-Gohst

[MikeB]

While we could generate a pulse wider than the 125% currently available, it is very unlikely the Tx and Rx modules will handle them anyway. Unlike non-2.4GHz systems the modules actually measure the pulses, transmit them in digital form, then the receiver regenerates the servo pulses.
I think you will need a pulse stretecher on the receiver output to do this.

Mike.

[kaos]

any one has experience with this one: http://dionysusdesign.com/product_info. ... cts_id/195

[MikeB]

I am using a pulse stretcher, on my Mosquito for the gear, that I made myself. The only problem is it is a bit bigger than it might be, provides a slow function as well, and is based on a PIC processor programmed in assembly. This makes it difficult to change quickly. I can post details if it sounds useful, but I don't have time to do any changes to it.

Mike.