This is my attempt at a low power consuming rig for mid-range flying, utilising Frsky's R9Slim and R9M transmitter module.
Build was so simple once I had the 3D print done for the antenna combo. Lots of room in the frame, receiver is easily accessible for binding/firmware changes, which is essential as firmware has regular updates, and if you want to change power output of R9M, you have to re-bind.
Can't really add any build tips, as I don't think you will need any, it's a good quality frame that's well thought out, I haven't seen a bad review of it, this is the 6" version.
I have opted for a high(ish) power VTX to get the range, and intend to go up to 2 KM, which should be possible given our surrounding countryside and topography.
OSD displays avg cell volts, flight time, throttle %, mah used and of course RSSI.
Not many flights so far, but with a 1300mah 4S battery, I can cruise around for 13 minutes, keeping throttle at or below 30%, so that's all good.
Travelled 800m out and back from a high point with no video break-up and 90%+ RSSI on 500mW R9M output, and 600mW of VTX power.
I know that's not far, but need to build my own confidence as much as anything, before stretching it out a bit.
I have FCC firmware loaded to the Frsky kit, as the options for power/telemetry on EU firmware seems to be somewhat restrictive, no failsafes thus far.
Thinking of adding GPS for interest's sake.
Oh, I tried some tri-blade props, and it's much more dynamic as you'd imagine, rolls spins and tricks are all possible so can swap props if I want some of that stuff too.
If anyone reads this and can offer any help/tips and suggestions to improve things, then I'm all ears, TIA.