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9x modifications for Open9x / ER9x

Hardware :

- 1x USB ISP programmer for Atmega : approx. 3 on eBay (search with keywords USBASP Programmer ATMEGA )

- 1x Turnigy backlight- 2x LiPo / LiIon cells (eBay)- 1x FrSky DHT module- 1x BS170 transistor- 1x low drop 5 V voltage regulator MCP1826 ou LM2940 (SOT-223-3 case)- 2(3)x 220 ohms SMD resistors (1206 case)- 1x 470 ohms SMD resistor (1206 case)

- 2(1)x 1 k ohms SMD resistor(s) (1206 case)- 1x connector set (socket + jack) miniDIN for IC (5 points + ground or 6 points)- wrapping wire- servo wires- 2x female 2.54 mm connectors- 1x male 2.54 mm connectors- 1x 3 pos. slide inverter for IC- 1x double-sided foam tape- 1x 15 Wsolding iron + 0.8 mm solder- 1x multimeter with continuity test feature

Software :

- UBSasp drivers : http://www.fischl.de/usbasp/- companion 9x : http://code.google.com/p/companion9x/

LiIon high capacity battery (how to choose) :

- http://lygte-info.dk/info/Batteries18650-2011%20UK.html- http://lygte-info.dk/review/batteries2012/Common18650Summary%20UK.html

Some practical advices :- Work in peace and with adequate lighting : welding the wrapping on the

microcontroller or the tracks of the FrSky module require an accurate gesture.- Do not hesitate to identify the cables with annotated tape paper, removed when the

work is done, it may prevent some mistakes.- Final inspection before closing the radio : plug the programmer on the radio and test

the electrical continuity of the entire wiring (programmer to microcontroller). In thesame time, it verifies that there is no inversion of wiring.

- Using a 5 V low drop voltage regulator allows to set the low batterie alarm at 6 Vintead of 7 V and so significantly increase the time of use with a LiPo 2S battery.

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ISP (In System Programming) ATMEGA microcontroller and backlight wiring

FrSky telemetry

modifications :

220 ohms resistors

Remove theses resistors

To miniDIN

470 ohms resistor

(verticaly welded)

Backlight

+ battLiPo / Li-Ion 2SLiFe 3s

To backlight

5V regulator (to replace if

LiPo 2S)

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FrSky telemetry routing

Cut the trace (front and back of

the card)

Cut the trace

FrSky split washer inserted

slightly tight then glue with

cyanoacrylate

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ISP routing and battery installation

Socket glued with cyanoacrylate(weld the wiring before)

No equilibrating wires (cells with

protecting PCB inside)

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FrSky DHT wireless + direct TTL modification

Cut the two traces

1 k ohms resistors

Reinforcing stay

from MISO

to MOSI

Cut off this face

Inverter welded on its case

Scrape the varnish with a

scalpel beforehand

IMPORTANT NOTE : in case of"NO DATA" message due to some

RF noise, use 220 ohms resistor(or less if necessary) on MOSI line

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FrSky DHT module installation

2 mm plywood cover, painted

or varnished, and slightlyadjusted to maintain tight

without screw

Use double-sided foam tape at

the bottom of the housing

The push-button should

be just flush

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miniDIN jack installation on AVR programmer

Wires tags