Buddy Box with LRS...?

[Derrick]

So AMA has this these rules in order to fly FPV at an AMA field:

1. An FPV-equipped model must be flown by two AMA members utilizing
a buddy-box system. The pilot in command must be on the primary
transmitter, maintain visual contact, and be prepared to assume
control in the event of a problem.

2. The operational range of the model is limited to the pilot in command’s
visual line of sight as defined in the Official AMA National Model
Aircraft Safety Code (see Radio Control, item 9).

3. The flight path of model operations shall be limited to the designated
flying site and approved overfly area.

4. The model weight and speed shall be limited to a maximum of 10
pounds and 60 miles per hour.

Short of breaking into your radio and voiding your radio's warranty... is there any way to buddy box a radio that uses the trainer port to feed a LRS?

I was thinking that there must be some form of pass through connector that could be used. Just not up on my electrical connectors... then there is the issue of current decreasing when splits paths, would this cause the signal to drop to unacceptable levels for the LRS to pickup and read?

using a long range system with these rules is pointless though, because of the whole LOS thing. Just curious if anyone has thought about how to do this.

Derrick

[aeryck]

There is one way but it's a roundabout way of doing it... It basically frees up the trainer port for buddy boxing.

Instead of wiring the UHF to the transmitter, use either A: a receiver capable of PPM Sum output, or B: a standard receiver and a PWM - PPM encoder. The UHF is hooked to the PPM stream of either the receiver or PWM-PPM encoder, so you are transmitting from your stock radio to the radio's own receiver (2.4GHz/72MHz), and the receiver's output is sent into the UHF Tx.

I've used such a system before to enable flying from the living room.. sitting on the couch with the Tx, broadcasting to the 2.4GHz Rx sitting outside with the UHF attached to it, so the UHF transmission is not attenuated from going through walls.

Edit:

Of course, if you have a Futaba module-based radio, you can wire your UHF Tx to the module port instead of the trainer port, and still be able to buddy-box with UHF.

[LLD]

Of course, if you have a Futaba module-based radio, you can wire your UHF Tx to the module port instead of the trainer port, and still be able to buddy-box with UHF.

That is exactly how I do it on my 9C. I take ppm from the module pins and have the trainer port free for a buddy box. I have been using this quite often for people who want to try fpv, works very well

Ro