Realacc RFX185 (aka QAV ULX)

By wrong17 on Jun 03, 2018

5  313  0

The revival of Realacc RFX185 (aka QAV ULX)! After moving from Spektrum to FrSky I never replaced the RX for this frame, so it just hung on the wall of my garage for a while. A bit has changed since I first built this frame, so I was able to trim some fat off my setup. Now I am using a lighter Camera, VTX and RX. Because of these items are smaller and lighter I was able to remove some extra mounting hardware too. I was able to trim about 33g of excess weight. I plan to replace the stainless-steel cap screws to Titanium button heads, so I should lose a few more grams there.

During my first maiden flight with stock Butterflight PIDs this thing was on rails!!! I could not believe how well if flew, it was like flying a 3inch quad. This might be an older clone of a QAV ULX but it flies great.

Just for fun I did a few speed runs and the best pass that was caught on the radar gun was 77mph:

Photos

Part List

Frame

Realacc RFX185 RFX160 4mm Carbon Fiber FPV Racing Frame RC Drone w/ 5V & 12V PDB Supports 4-5 Inch Prop (5 builds)
Banggood.com
$20.19

Flight Controller

DYS F4 Flight Controller (Poker Face) (141 builds)
Getfpv.com
$38.99

ESCs

DYS F30A 4-in-1 ESC BLHeli_S Dshot (74 builds)
Getfpv.com
$44.99

Motors

4 x DYS SE2205 2300 KV Special Edition FPV Racing Motor (5 builds)
Fpvheadquarters.com
$51.96

Propellers

DAL 5x4.6 - 3 Blade, Black Cyclone Propeller - T5046C (Set of 4) (394 builds)
Getfpv.com
$1.99

FPV Camera

Foxeer Predator Micro Pro 1000TVL 1.8mm 110 Degree M8 Lens Super WDR FPV Camera With OSD DC5V-40V Low Latency - Blue
Heli-nation.com
$36.90

FPV Transmitter

Eachine VTX03 Super Mini 5.8G 72CH 0/25mW/50mw/200mW Switchable FPV Transmitter (426 builds)
Banggood.com
$12.22

Receiver

FrSky R-XSR 2.4GHz 16CH ACCST Micro Receiver w/ S-Bus & CPPM (863 builds)
Getfpv.com
$20.99

Batteries

AHTECH Infinity 1500mah 14.8V 90C 4S1P Race Spec Lipo Battery for RC Drone (23 builds)
Banggood.com
$28.18

Radio

Team BlackSheep TBS TANGO 2 PRO RC RADIO (22 builds)
Heli-nation.com
$199.99

Goggles

DJI Digital HD FPV Goggles (86 builds)
Getfpv.com
$529.00

HD Camera

GoPro HERO8 Black - Waterproof Action Camera with Touch Screen 4K Ultra HD Video 12MP Photos 1080p Live Streaming Stabilization (14 builds)
Amazon.com
$308.00

HD Camera

Insta360 GO Stabilized Camera FlowState Stabilization Mount Anywhere Hands Free Auto Edit Water Resistant Slow-mo Sport Action V (2 builds)
Amazon.com
$29.99

Video Receiver

ImmersionRC rapidFIRE w/ Analog PLUS Goggle Receiver Module (145 builds)
Getfpv.com
$149.99

Battery Charger

HOTA D6 PRO Charger AC200W DC650W 15A (6 builds)
Pyrodrone.com
$119.00

Soldering Iron

TS100 Portable Programmable Smart Soldering Iron (171 builds)
Racedayquads.com
$51.29

Backpack

Lowepro QuadGuard BP X3 - Drone Backpack for 4 FPV Quad Racing Drones and 15" Laptop w/Exterior Mounts (Black)
Amazon.com
$286.00

Accessories

BoYz analog bay v2 for DJI FPV goggles
Themakerboyz.com
$23.98

Accessories

Analog FPV FatShark Module Adapter V2 for DJI Digital FPV Goggles
Pyrodrone.com
$11.99

Accessories

FuriousFPV Smart Power Case V2
Helidirect.com
See Site
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