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Mar 27, 2016, 08:07 AM
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Mini-Review

LONGING LY-250 "Red Bee" (in construction)




INTRODUCTION

Longing is new chinese quadcopter compagny offering a full and complete 250mm 5.8G FPV racer solution including a 7" FPV monitor.
Here with LY-250 Red Bee no big revolutions are announced, the main goal is to deliver a cheap real brushless solution for advanced beginners. Let's discover this YaR (Yet another Racer).


BOX CONTENT



+ 1 x Longing LY-250 (with a 2x1S 2500Ah Li-Ion batteries)
+ 1 x Transmitter (using 2x1S 2500Ah included)
+ 1 x 7" FPV monitor
+ 1 x 5.8G linear antenna
+ 1 x Bind plug
+ 1 x USB charging cable
+ 4 x 5040 triblade spare props (2 CW, 2 CCW)
+ 4 x 6040 biblade spare props (2 CW, 2 CCW)
+ 1 x Screwdriver
+ 1 x Hexscrewdriver
+ 1 x Camera mount
+ 1 x Instruction manual (English)

OVERVIEW

Here no sign of 3K carbon/fiber glass, all elements are nylon based. The nylon material here is assumed to be re-inforced. Of course not being as solid as a real 3K solution but should be strong and flexible enough to be crash resistant.

-Front view

The chassis design is ultra classic with H shape. Here no sign of front LEDs ...so for night flight you will need to install them



With the three blades 5040 props isntalled



-Side view

The LY-250 uses a classic helicopter landing skid and offers a ground clearance of 4cm






-Rear view

The upper canopy part is clipsed by this central piece you have to rotate of 90 degrees to free it.



You can guess the two 2.4G antenna associated with the FlySky receiver with diversity. A better strategy would have been to install them vertically in Y/quadrature to increase the radio control range.

-Upper view



-Bottom view

Two originalities here. The first one are these two "big" Li-ion accu, much larger than AA model. The second is this display showing the current voltage.



The battery compartement. A very important point: you must be very vigilant when you insert battery to not invert the sens of their insertation. Please notice Inside the compartement the "+" for each column.





The main power connector must be slided to the left to turn on the LY-250. It's a big switch creating a direct connexion with the accus.



If you plan to install a real LiPo battery, you will need to remove the power switch connector as showed below

LONGING LY-250 LY250 DARK KNIGH/RED BEE 5.8G FPV RC Racing Drone change battery (4 min 29 sec)


On the front side is installed a heatsink to cool the main 5.8G VTX but no sign of a DIP swtich the Vfreq selection





-Weight

Around 417g, an average weight for a 250g racer.




Prop

Some tri-blade 5040 props with 5mm of hub diameter





Motors

2206 type









Li-Ion battery

Two larger 2500mAh Li-ion accumulator are installed. If the mAh capacity sounds great, first of all here we have out of the box a "2S" powering and second point, the discharge rate is rather low: 8C no very compatible with big verticul punches required from flips.



Why not install 3xsmaller Li-ion batteries instead, for example 3x1600... probaby could fit the battery bay and could offer 3S power.

Battery charger







On the battery charger, the two red LEDs stay turned on even if the battery are fully charged. The end of the battery charging can be visualized only on the power unit: red when charging and to turn to greed when the job is done. It takes 2 hours to charge.

FPV-Camera module

A simple 420TVL FPV have been installed ... so clearly this camera won't offer the best image fidelity we can expect from a PAL or NTSC video link. A good news at least, you can set the lens angle orientation between [-30 ; +15]deg.



You need to slide the FPV-cam combo. Maybe, in a future, another model including HDrecording can be installed.



No DIP switch to select the Vfreq ;(. The default Vfreq is set to A1=5865MHz



The 5.8G linear antenna is directly soldered .... Here no uFL/IPX male connector ...




Internally, you can guess the 3 pads (CS1,CS2 & CS3) allowing eventually to select one of 8 video frequencies. One mod consists in a 3position DIP switch.

Last edited by SeByDocKy; Mar 28, 2016 at 03:01 AM.
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Mar 27, 2016, 08:08 AM
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Disassembling



A large PDB including the 4-in-1 ESC system. In the central part, mount over anti-vibration square, a FlySky receiver (with A7105 RF chip) is here including a 2.4G diversity feature. Over the receiver, the Flight controller, probably a min-Atom CC3D board. The FC is flipped of 90 degrees.



Notice, I was not able to fully access the the FC parameters with Open-pilot (or either CF/BF). Probably a prioritary firmware is here.

The last free servo plug represents the bind plug to match the FlySky receiver with another compatible radio.







No information about ESC caracteristics, but from the previous video, there are supporting 4S voltage....



A buzzer is here, not very loud alerting the LVC.




Action-cam mount












LONGING LY-250 holding action cam (Courtesy Tmart) (3 min 28 sec)


As you can see with the camera mount, unfortunatly some jellos are introduced ...

Transmitter




Even if the longing logo appeared on top, the radio is nothing else than a i6 flysky transmitter with 3x2-way switches and one unique 3-way (switchC) to select one of the three flight modes: stable(horizon)/stunt(air-mode)/manual(accro).



Two voltages are displayed, the first one is the direct voltage given by the 2 Li-Ion cells (~8.4V), the second is the voltage after the +5V internal Vreg of the LY-250... Like the Flying3D X6/X8, it's a strange idea to monitor the internal +5V voltage (after the Vreg). In practice, this internal voltage varies just a few from large variation of the LY-250 batterie's voltage.



Versus the original model, you have two extra switch buttons located in the rear side



Notice on the top left shoulder location, the power connector for the FPV screen



-Failsafe test

LONGING LY-250 "Red Bee" Failsafe test (Courtesy Tmart) (0 min 33 sec)



FPV monitor










Bad news.... blue screen is here when the signal is lost .... The angle of view is a little bit lmited IMHO around 40 degrees, but the luminosity is strong enough to handle strong daylights.



No DIP switch to select the Vfreq.... and builtin DVR





FIRST USAGE

Longing FY-250 "Red Bee" first demo flight (Courtesy Tmart) (10 min 5 sec)


Even with the 2S power, the LY-250 is quiet agile, nimble. Of course don't expect amazing vertical punches as you can see. The "only" 8C discharge doesn't help ... but I am really very confident than with a 3S battery, it will be a complete different story. Associated with the 5040 triblade props, the LY-250 is super stable !!! default PIDs settings are tuned. Pitch & rolls rates are already sporty. The switchC in middle position offer super tight flips super super easy to perform. Probably an "Air-mode" behind the scene. The control range is super, the two way flysky protocol is really efficient within a radius of 300-400m (expect more range if you install antennas vertically). The FPV range despite to use linear polarization offers at least a good 200-250m. Here again, a mod would consist to install a uFL/IPX male connector, a RG178 coaxial cable and a real CL antenna. Flight times are lower than advertized ones... around 8min for me... I deeply regret the absence of any OSD informations of the FPV screen and some strong frontal LEDs for night flights ...

CONCLUSIONS

Is a the LONGING a bad FPV racer ? Absolutly not .... a fantastic one ? neither .... In practice this machine is first of all more a super stable machine for FPV cruizing (with the default Li-ion batteries). I really like that everything you need to fly FPV is here. A good point. After, some détails can be largely improved: the blue screen of the FPV monitor, a higher res FPV camera, and I think a direct 3S power system would have been a better choice. In practice the big open question is the robusness of the nylon material structure... With 417g at full speed (100km/h), it won't survive to any frontal or latteral crash. Associated with this "big" question is the availability of the spare parts. Anyway, the more important are already here: a pleasant, fun, fast machine perfectly adapted to intermediate beginners who want a real brushless system.

UNBOXING

Longing FY-250 "Red Bee" Unboxing and first analysis (Courtesy Tmart) (27 min 41 sec)


PROS

+ Full RTF solution including a 7" FPV monitor
+ Beautiful packaging
+ Flight modes well tuned from beginners to full accro FPV racers
+ Super stable machine
+ Voltage displayed on the quad itself
+ Compatible with 3S-4S LiPo
+ FPV monitor powered by the radio directly
+ Safer Li-Ion batteries (versus LiPo models)

CONS

- No Vfreq DIP switches (for both VTX & VRX sides)
- Blue screen for the 7" FPV monitor
- Default 2S batteries not enough strong => more a cruzer machine than a racer
- 8min of flight time duration (instead of advertised 15min)
- Unibody lower structure (arm replacement will require full maintenance)
- No LEDs for night flights
- 420TVL FPV cam with average light sensitivity
- 5.8G antenna directly soldered (no uFL/IPX connector)
- Action camera mount introduces jello
- No OSD/telemetry
- Not 100% compatible with Open Pilot
- We can find competitors 3K carbon based for the same price range
- Need battery compartement modding to install standard LiPo battery
- Spare parts availability ?

This quadcopter have been courtesy provided by Tmart in order to make a fair and not biased review. I would like to thank them for this attitude.
You can find it actually for 335USD at http://www.tmart.com/LY-250-5.8G-FPV-Real-time-Transmission-with-7-Inch-Monitor-Power-Distribution-RED-BEE-Thrilled-Racing-RC-Drone-Quadcopter-Longing-Innovation-RTF-Red_p340794.html
Last edited by SeByDocKy; Mar 29, 2016 at 03:43 AM.
Mar 27, 2016, 08:08 AM
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Mar 27, 2016, 01:01 PM
Fan of just about anything RC
SoloProFan's Avatar
And another brushless racer, it seems like a tidal wave, I lost count.

Seems like a very decent offering, shame about the missing OSD. Do you think this could be easily added?
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Mar 27, 2016, 01:12 PM
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Added new photos, video and text ...
Mar 27, 2016, 01:15 PM
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Quote:
Originally Posted by SoloProFan View Post
And another brushless racer, it seems like a tidal wave, I lost count.

Seems like a very decent offering, shame about the missing OSD. Do you think this could be easily added?

Should be not so so hard I guess but it will require to open this FPV-VTX module, desolder some connexions....to interconnect the OSD
Mar 27, 2016, 04:24 PM
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At that price isn't a Eachine 250 RTF a better option? It's cheaper, spare parts are widely available, support, programmable etc.
Mar 28, 2016, 03:05 AM
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Quote:
Originally Posted by DroneRequired View Post
At that price isn't a Eachine 250 RTF a better option? It's cheaper, spare parts are widely available, support, programmable etc.
I think the price of the LY-250 will decrease a bit to be ajusted to other competitor.
Mar 28, 2016, 03:28 AM
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Quote:
Originally Posted by SeByDocKy View Post
I think the price of the LY-250 will decrease a bit to be ajusted to other competitor.
I would think so too, it seems to be a good quad with potential. But the Cheerson version is about 100USD cheaper.
Mar 29, 2016, 03:43 AM
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SeByDocKy's Avatar
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-Failsafe test

LONGING LY-250 "Red Bee" Failsafe test (Courtesy Tmart) (0 min 33 sec)
Apr 07, 2016, 09:43 PM
Registered User

Short Circuit Test on LY-250 RED BEE


Test on radio:

LY-250 Transmitter Short Circuit TEST (1 min 18 sec)



Test on LY-250 Aircraft

TEST: What Happens if You Wrongly Load the Battery into LY-250 RED BEE Aircraft (0 min 48 sec)
Apr 07, 2016, 09:53 PM
Registered User

How to Mount Your Action Camera onto LY-250 FPV Racing Quad


Easy DIY to FPV fly with your camera

How to Mount Your Action Camera onto LY-250 FPV Racing Quad (1 min 40 sec)
Apr 11, 2016, 09:14 PM
Registered User
Fly LY-250 without Landing Gear
Quick Disassembly
Easy DIY


Fly LY-250 FPV Racing without Landing Gear (3 min 1 sec)
Sep 09, 2016, 01:40 PM
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rcdude07's Avatar
I posted my mini-review over on this thread:

https://www.rcgroups.com/forums/show...0&postcount=20
Nov 09, 2018, 10:52 AM
DFS#000178
Rampage's Avatar
I picked up one of these from HobbyKing. Figured $140 shipped was a really good deal. So far it definitely appears to be except for one issue.

The batteries don't seem to be charging.

When I put the batteries in the quad and the TX, the quad reads +-7.3 volts and on the TX reads INTV of like 4.9v.

I get about 1.5-2 minutes of flight time before the alarm goes off and the LEDs start blinking.

What's the deal? I run the batteries through the charger until the LED on the power adapter turns green. Do I have to do this multiple times per charging session or is there something wrong with my charger?

I might just look for a higher-quality charger.


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