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Oct 16, 2015, 03:44 PM
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Mini-Review

JJRC H11D "Eye Of God" (Under construction)




INTRODUCTION

Here is a new 5.8G mini FPV quadcopter from JJRC. This new model introduces the possibility to set the lens tilt orientation via the radio, a real positive point for a toy. This model advertises also 11min of flight duration, a 720p camera including a 5.8G video transmitter.

BOX CONTENT



+ 1 x JJRC H11D (with a 1S 1100mAh LiPo directly soldered)
+ 1 x Transmitter (using 3xAAA batteries not included)
+ 1 x 4.3" FPV monitor
+ 1 x USB charger with JST connector (main LiPo)
+ 1 x USB chager with 1.25mm microJST connector (FPV cam combo) + 1.25 jack connector (FPV monitor)
+ 1 x 2GB microSD card
+ 1 x USB microSD card reader
+ 4 x Spare props (2 CW, 2 CCW)
+ 4 x Props guard
+ 1 x Screwdriver

Notice the absence of instruction manual. Maybe I received a pre-release version

OVERVIEW

The H11D is a miniquadcopter, gear driven equiped of 8.5mm coreless motors, latteral bands of LEDs for night flying and (the more important) a new HDready FPV cam combo broadcasting in the 5.8G band so without interferences with the radio control part working in 2.4G

-Front view

You will need to tight 8 tiny screws to attach the landing gear. The ground clearance is approximatively of 4-5cm, largely enough to welcome the FPVcam combo.



A frontral white LED can be found.

You can already notice the design of the Props now more similar to the model found with brushless motors. These props offer more "pitch" so more thrust capacity but less "sporty" attitudes.

-Side view



There are two bands of 5 LEDs each brighting a lot even in daylight

-Rear view



-Upper view



Some holes are found nearby motors to let the airflow cool them...

-Bottom view

The quad is equiped of a JST connector, pretty standard for this category size. It won't be difficult to find some battery replacement models



It's always a positive point, but you have a tiny power switch button. There is also a lot of free room to welcome a longer LiPo



The total weight



To this weight, you have to add the LiPo weight (27.2g) and the camera module (23.7g). The total weight without prop guard is 146g, a little bit heavy but luckely props design are efficient.





LiPo

No clear reference for this model, but it's a 1S 1100mAh model. No discharge rate information. It takes at least 1h to charge it with the USB charger.









Camera FPV module

As for many "G" model, with the H11D, you have camera FPV combo "Plug & Fly". The camera is able to record in 720p resolution while broadcasting live-feedback in NTSC and in one of the 8 frequencies of the Boscam band.

A mini DIP 3 positions switch allow to select among one of the 8 frequencies in the Boscam (E) band. The 5.8G antenna is a simple linear one jailed into the silver metallic part. With this positionning, the video link will be weak when the quad will be front of you in the same horizontal plan. In the other hand, a stronger video will be found when the H11D will be flying in altitude.



A tiny switch to turn on/off it independently as well as a 1.25mm miniJST connector to charge the internal LiPo.



No indication of the lens sensor size, but probably a 1/4" CMOS model




4 wires are connector to this 5 positions 1.25micro JST connector. I guess one is the ground, one to trigger video and the last two to triger the lens's tilting.





A tiny coreless motor is installed to tilt the lens



Unfortunately, the lens mount is in M6 format



Actually no widelens model is available with this original format

The camera lens sensor is attached with a 24pins ribbons, so compatible in size with the 808#16 lens D model



The RTC6705 chip is used as FM modulator. The 5.8G signal is broadcasted in NTSC format. No unformation about emiited power is given but I think it's the same that the WLtoys/JJRC/Syma model, i.e around 100mW.



The very good news about this combo is the absence of frame rate drop when 720p recording is turned on !!! (versus other design found in the V686G for example).This point can almost justify the H11D's order (I am kidding).

FPV Monitor



The 4.3 screen have a matte display, it's a positive point. The visibility in daylights condition is largely improved vs V6x6G series



As you can see, the 5.8G antenna is now directly inserted inside the chassis. No more SMA connector like former FPV models.
If you plan to install a cloverleaf antenna, you will need to unsolder the actual antenna before to solder a RG318/RG178 coaxial cable



The mini DIP switch selects one of the eight frequencies in the Boscam Band



No specific reference for the VRX chip. In practice, the RX sensitivity is correct, you can expect at least 100m of FPV range wit this bundle.





No AVout available


Disassembling





The main PCB board is equiped of a invensense 6050C for this 6-axis stabilization, a 32bit ARM core and a XN297 RF chip.



The antenna is correctly tuned to around 29mm



Motors

A nice feature is introduced with the H11D, the possibility to replace a motor without disassembling all the machine



Some 8.5mmx20mm coreless model are installed



Unfortunately no ball-bearings are installed, only some bronze bushings. There are 3mmx6mmx2mm format, a common size for most of miniquadcopter size (V222, etc...)







I strongly advice to install 8 real ball-bearings
Last edited by SeByDocKy; Oct 17, 2015 at 01:55 AM.
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Oct 16, 2015, 03:44 PM
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Transmitter

A lot of button can be found on this gamepad style radio: 2 bumper shoulder ones, 6 central ones and 2 x 4 "a la playstation". A retractible FPV monitor mount can be found. You have to pull on the central part from the bottom part to release it.



The left shoulder button cycles on the 3 speed modes. For each of them all the 3 rates (A,E,R) are proportional. If you long-press on it, you can turn on/off the lights. The right shoulder button acticates flips. Among the 6 central buttons, especially the left columns' ones, only the two last one are operational. One engages the "one key return", a ersatz of a real "RTH" without any compass, baro & GPS. In practice such feature becomes more and more innacurate versus time/distance. The last one turns on/off headless mode. Notice, I didn't find the stick command to set/calibrate the headless reference (Under investigation). For the right column, the upper one is the power button. The last two ones are dedicaced to photo and video recording. For the "playstation" buttons, only the left section is interesting, especially the up and down buttons which allow to control the tilt of the lens orientation. One click increase/decrease the orientation of around 5-10 degrees IMHO.


With the FPV monitor installed



In practice, it's not so heavy to carry... It's a positive point.

The radio protocol is a new one (again) from JJRC .... what's a pity, why do they need to change protocol every 2-3 models ... with several branches in paralel.





Behind the protection, you can find a XN297 RF chip. I stronly suspect the absence of a LNA+PA state for this daughter board limiting drastically the control range



Another major problem is the fail safe behaviour. Between 4s up to 6s of potential flyaway when the connexion is lost. Some delay in command are observed when the H11D is reaching a nominal radius.

FIRST USAGE

JJRC H11D outdoors test (Courtesy Banggood) (15 min 59 sec)


As you can see in the first part of the video, the control range out of the box is ridiculus for a FPV model, even for a non-FPV model it's a real shame !!!! How it's possible to release such product without a real range testing ? What JJRC expect ? Out of the box, the control range is around 20-25m maximum.... More !!! when you are flying close to this distance, as soon as you are loosing your connexion, you have a potential flyaway during [4-6s] before motors to stop. Imagine the distance you can perform during this "eternity". One more time, it's criminal to do that. Cherry on the cake, the videos are just "Jello of pixels" ... killing all the excellent performances of the camera FPV combo...
In term of quadcopter (when you have the control), the H11D is not bad at all, a relatively stable flyer. The leds are very visible even in daylights. I found the gear system very noisy in action. Probably some real ball-bearing should reduce friction and reduce that noise. Notice you can only perform flips when the camera module is not installed. The 3D button is inactive (probably active for another JJRC model).
The flying duration with the camera installed is around 7-8 min, 11 without so a positive point.

In a second attempt, after the antenna mod (both RX & TX parts), the control range was slightly improved (30-35m). It's very frustating since the camera link is very good for this distance... I also installed some piece of foam between the camera module and the belly part of the H11D. It helps a lot to reduce to jello effect. Another "must to do" for this model. With the Jello effect reduced, the video are good

CONCLUSIONS

To make short: until JJRC don't offer a new revision of this model (with probably a fixed radio), avoid this model. You will be frustrated to have a good 5.8G FPV link while to have in the same time an horrible 2.4G connexion. How JJRC can distribute such model ? Even a 10min testing can reveal 95% of the problems for the H11D. It's very frustrating because the camera FPV combo is working well standalone. In fact, if this one can be sold separatly, probably it would be an even better option than the Syma FPV Kit (absoluptly no frame rate drop, 808#16 lens D compatible and orientable lens, 100mW emitted). The real question is "why the control range is so poor". IMHO, the radio RF PCB don't include any PA+LNA stage. It means in practice the emitted power is very weak far from the 100mW/20dBm maximum allowed in the 2.4G band. The best scenario which can save this model would be to Deviatization of the radio protocol: the output power would be maximum.The "Eye of God" is in practive completly blind faced on its own problems ....




UNBOXING

JJRC H11D Unboxing and quick analysis (Courtesy Banggood) (23 min 41 sec)


PROS


+ Easy motor replacement
+ Night flyer
+ Matte FPV monitor
+ Lightweight radio+FPV monitor
+ Ajustable lens orientation via the radio
+ No frame rate drop when recording
+ Good 720p camera
+ Good FPV range
+ Compatible with 808#16 sensor+lens via the 24pins ribbon cable
+ Good flying duration with and without the FPV camera combo

CONS

- Extremely poor control range
- Videos full of jello out of the box
- Between 4-6s of potential flyaway when the transmission is lost
- YAP (Yet Another Protocol, XN297 based so luckely potentially hackable for DeviationTX)
- No SMA connector for the FPV monitor
- No Ballbearings (3mmx6mmx2mm)
- M6 lens mount
- No instruction manual

This quadcopter have been courtesy provided by Banggood in order to make a fair and not biased review. I would like to thanks them for this attitude.
You can find it actually for 90USD at http://www.banggood.com/JJRC-H11D-5_8G-FPV-2_0MP-HD-Camera-Headless-Mode-2_4G-4CH-6Axis-RC-Quadcopter-RTF-p-994589.html


Ball bearings (IDxODxW) 3mmx6mmx2mm replacement
http://www.banggood.com/Wholesale-MJX-F47-F647-RC-Helicopter-Spare-Parts-Bearing-p-57426.html
Last edited by SeByDocKy; Oct 17, 2015 at 01:45 AM.
Oct 16, 2015, 03:45 PM
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- Antenna mods





- 808#16 lens D installation







Last edited by SeByDocKy; Oct 16, 2015 at 04:27 PM.
Oct 16, 2015, 04:08 PM
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Some interesting inside shots. I've seen the quad from the inside when attempting the antenna mod, but after being so disappointed with the low range, low forward pitch even in high rates, and the massive jello effect, I didn't feel like spending more time on the H11D.

Btw, it's easy to remove the shielding tape from the RF board in the transmitter, the blobs of hot glue come off easily. For a moment I considered installing an SMA connector on the transmitter, and a 3dbi antenna, to gain some extra range, but the low forward pitch, making the quad needing to go sideways into a mild breeze to make headway, made me close the transmitter back up again. I re-attached the foil tape with some normal Tesa "perfect tape", to replace the removed patches of hot glue.

Btw, you mention good FPV range. What range are you getting?
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Oct 16, 2015, 04:34 PM
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Quote:
Originally Posted by SoloProFan
Some interesting inside shots. I've seen the quad from the inside when attempting the antenna mod, but after being so disappointed with the low range, low forward pitch even in high rates, and the massive jello effect, I didn't feel like spending more time on the H11D.

Btw, it's easy to remove the shielding tape from the RF board in the transmitter, the blobs of hot glue come off easily. For a moment I considered installing an SMA connector on the transmitter, and a 3dbi antenna, to gain some extra range, but the low forward pitch, making the quad needing to go sideways into a mild breeze to make headway, made me close the transmitter back up again. I re-attached the foil tape with some normal Tesa "perfect tape", to replace the removed patches of hot glue.

Btw, you mention good FPV range. What range are you getting?

For the jello, as soon as I inserted some extra foam in sandwitch between the camera module and the belly part, the Jello have been reduced a lot IMHO (see second part of my outdoors test).

The FPV range is around 100m in LOS condtions, much more if you use a receiver with a better sensitibity
Oct 16, 2015, 05:05 PM
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100 metres with still steady image, or a lot of noise lines? Also, since the range on the quad is lower, did you test the FPV range on another quad, or just quad put down on the ground and walking away with the monitor?
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Oct 17, 2015, 12:10 AM
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Quote:
Originally Posted by SoloProFan
100 metres with still steady image, or a lot of noise lines? Also, since the range on the quad is lower, did you test the FPV range on another quad, or just quad put down on the ground and walking away with the monitor?
Second option....

P.S I am actually adding a lot of détails now in #1 & #2 (I was tired last evening )
Oct 17, 2015, 01:18 AM
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Review in beta-stable version ...
Oct 17, 2015, 01:33 PM
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Thanks for the review.

So much promise yet fall so short. They got the hardest FPV part right but fail on the most basic range issue. Hope JJRC can fix the range issue and add ball bearings to the motor.

The search for low cost and good quality FPV drones goes on.....
Oct 17, 2015, 01:45 PM
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Quote:
Originally Posted by Serenade
Thanks for the review.

So much promise yet fall so short. They got the hardest FPV part right but fail on the most basic range issue. Hope JJRC can fix the range issue and add ball bearings to the motor.

The search for low cost and good quality FPV drones goes on.....
For the ball bearings, I am pessimistic but I guess they will fix the radio coz sales will be catastrophic.

Yes the race for a good 5.8G FPV toy quadcopter is still open....
It's nor hard : take a V686G first edition and add this new variant camera VTX combo
Oct 18, 2015, 07:19 AM
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Quote:
Originally Posted by SeByDocKy
For the ball bearings, I am pessimistic but I guess they will fix the radio coz sales will be catastrophic.

Yes the race for a good 5.8G FPV toy quadcopter is still open....
It's nor hard : take a V686G first edition and add this new variant camera VTX combo

Or maybe a FQ777-957 board in the H11D? Would fit the range issue, and the flight controller is programmed very sporty too. Just wonder if the camera of the H11D can be stopped and started with the 957 board.
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Oct 18, 2015, 07:28 AM
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Quote:
Originally Posted by SoloProFan
Or maybe a FQ777-957 board in the H11D? Would fit the range issue, and the flight controller is programmed very sporty too. Just wonder if the camera of the H11D can be stopped and started with the 957 board.
Need also an extra channel for the camera tilting control
Oct 18, 2015, 07:36 AM
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Quote:
Originally Posted by SeByDocKy
Need also an extra channel for the camera tilting control

The V686G does have this extra channel?
Latest blog entry: For the love of the hobby!
Oct 18, 2015, 10:32 AM
Registered User
Just wonder when will Syma add 5.8GHz FPV to their X8C platform. Need something that can fight winds better in my area.
Last edited by Serenade; Oct 19, 2015 at 10:12 AM.
Oct 18, 2015, 10:40 AM
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Quote:
Originally Posted by SoloProFan
The V686G does have this extra channel?
I don't think so


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