Gemfan have recently released the 2540 Flash propeller to add to their growing library of micro propellers. This time rather than sticking with their 'Hulkie' naming on the 1940 and 2040 propellers, they have gone with 'flash' from their popular 5" 5152 prop.
The design is stylistically similar to the 5152 in that it is a swooping 3 bladed propeller with a pronounced wingtip. Colours currently available as below. I like the yellow as they are easy to find!
The material feels very much the same as the gemfan 2040 Hulkies which I reviewed here but the design is much more refined and so will not make any further comparisons as design will impact performance and durability more than material.
For testing I used my Leader 120. This is a popular model and I have put 80 odd packs through this one making it a good test mule. Also, I have experimented with other props like the Gemfan 3025 alongside the stock King kong 2840 for more than one point of reference.
Since this frame will fit a 2.8 inch 2840 prop there is plenty of room on a 2.5 inch 2540 without losing too much blade area. No issue installing so will move on to flight performance.
Performance on 2s
The first thing I noticed about these props is that they were very quiet. I flew in a reserve where there were several people enjoying the sun and very few people even noticed the quad flying about. The noise made was even less than the 2840s which are already very quiet. On 2s the performance was almost on par with the 2840s. I was able to hover at around 25% throttle with a 47g 950mah 2s battery and had flat out speed close to the 2840s. Cornering (grip) felt about 90% as good as the 2840s which is the grippiest quad/prop I have - even more than my 5" racing floss 2. Balance was excellent with no increase in jello at high throttle over the 2840s which have always been well balanced for me.
Battery life was definitely superior to the 2840 props. As you'll see from my pics below I got around 6 minutes from the 950mah battery with fairly heavy throttle flights as I was in a large reserve. This is about a minute more the the king kong 2840s with similar flying and comparable times to the Gemfan 3025 (although the 3025s were slower on 2s). It was an enjoyable 6 minutes too - the quad felt tight with these on.
Performance on 3s
For 3s testing I used my Turnigy Nantoech 3s 450mah 65C batteries that weigh approximately 45g.
The performance gap between the stock 2840 and new 2540 propellers were even less pronounced than on 2s. If there was a difference in performance compared to the 2840s in top speed or cornering grip I could not tell. The advantages did remain though - 2540 propellers were again more quiet and I had a similar increase in battery life: from roughly 3 minutes of hard flying to roughly 3.5 minutes+ hard flying (see below). Lastly at higher RPM I actually had less jello than any prop I have used on this quad before. This suggests they have excellent balance.
In short I got all of the benefits I enjoyed on 2s with none of the downsides.
Oddly enough I haven't had a crash worth speaking of yet. I'll update here once I've had a view and can give more of an opnion on this.
Simply put these are now my favourite prop on both 2s and 3s for the Leader 120. I can only guess that the more modern design helps get the efficiency up over the 2840 on 2s with very nearly the same top speed and grip through corners. On 3s the gap was even less and I'd struggle to tell the difference between these and the 2840s. The only real change was that there was less noise and more flight time.
In conclusion these will be my go-to prop from now on my leader 120 on 2s or 3s. The slight downside of marginally less top speed and cornering grip is easily outweighed by the reduced noise and improved battery life. Give them a try for yourself, they are inexpensive.
In part 1 of this review we looked at the specs of this quad and setup with betaflight 3.2.0. In this part I'll review the flight performance and any quirks.
Setting up the VTX
Before I get into the flight, just a word of warning that the VTX is set to 150mW to start. This may be fine for you but I like to start on 25mW as a baseline and if there are any antenna issues I know there will be less chance of cooking the VTX. Changing the channel and power is probably the most difficult I've found so far although the roomy frame at least makes access easy. I've put the original instructions below for reference but will also put my own notes as a native English speaker:
,When you power up the number of flashes of the green led indicates the channel and number of flashes of the red LED indicates the channel according to the designations to the left. Now, forget what the red and green leds mean.
Hold down the button for 3 seconds only till the red light goes off. The red light will flash once periodically meaning you are in 'channel' mode. Each short press of the button will change the channel as indicated by the number of flashes from the green LED.
Next hold the button again for 3 seconds as above. The red light will now flash twice periodically meaning you're in band mode. Now, each short press of the button will change band as indicated by the number of flashes by the green LED
Lastly, hold down the button for 3 seconds again. 3 flashes of the red LED now means you are in power set mode. Short pressing the button will cycle you between 25mW (1 green flash) or 150mW (2 green flashes). Finally holding down the button for 3 seconds again will take you out of setting mode indicated by both green and red LEDS blinking 3 times in unison. So confuse. Just set and never adjust again!
Setting up the camera - just use the stock settings
Good news: The CCD camera is actually a CCD camera and is fully adjustable via OSD. Bad news: no remote included. A compatible remote is only only about $3 from Banggood. You can argue that it should have been included but in reality the stock settings will satisfactory for 95% of the people that are likely to buy this quad. Chances are if this is not your first quad you'll have one or more floating around anyway.
Performance on 3s
Starting out using a 3s 450mah battery that I typically use on my Leader 120 (review here), I found performance to be fairly docile which is not surprising considering the low 3100kV rating of these motors. However, motors were quiet and smooth and flight performance was responsive and predicable - even with the mostly stock settings as covered in part 1. The LEDs on the back are nice and bright and certainly make it more interesting for spectators, particularly in the evenings. Flight time was very good given the battery capacity making this combination pretty usefully for someone new to FPV. However the combination of low motor kV and a fairly gently 3030 4-bladed prop felt me looking for more as an inermediate-ish pilot. I have some new props on order (3052 Gemfan flash) and I think these will make the 3s option more viable for me but I needed more instant gratification and went to 4s.
Performance on 4s
Unlike the small 3s batteries I don't have a small 4s. The smallest I currently have available is a 4s 1000mah turnigy graphene which weighs in at approx 140g. Ideally a 600-800mah battery at around 70-80g would be a better choice here - such as the 75g 4s Tattu 650mah.
Moving on though flight performance was much improved however the extra 75g weight penalty was noticeable, especially when pulling out of freestyle moves etc. To be fair though I have been flying the Leader 120 a lot recently which is a very 'floaty' quad. Much like on 3s performance was smooth and predictable but with better top end. Like on the 3s though I think there motors would benefit from a more agressive prop. The stock 3030 4-bladed props are better suited to a high-kV motor that needs additional grip from the extra bladed. With the right battery weight I think the Gemfan 3052 props I have on the way will offer the aggressive pitch along with a more modern design and greater efficiency but dropping 1 blade. The good think is though that here we are talking about changing props which are a disposable item rather than anything flawed with the frame, motors, esc, flight controller etc. They are the good kind of boring in that they all just do their job without fuss.
Flight time was pretty epic on these batteries. Check out the summary shots from my batteries below. When I got home the batteries will still measuring 3.75v per cell after resting!
On first impression, this frame is tough . I had a few crashes on some fairly hard-packed earth without any sign of issue although I'll really need more time to make a definitive conclusion. All of the components seem to be well enclosed and protected, no drama there.
This is a very well priced quad with a good performance range for a beginner stock. Although the realtively low kV motors will limit top speed, they give excellent efficiency which will translate as extended flight time and/or the ability to run a lighter/lower capabity battery with more nimble flight performance. For a more intermediate user some basic changes like a shift to more aggressive props will reward you with a solid flight experience. The equipment on board is well thought out and balanced. This means it is able to do that job that is expected of it at a very impressive price point. The frame appears to be exceptionally durable especially given the compact size and I am hopeful that this will withstand a lot of abuse.
Looking for a negative though the tradeoff of a durable frame in this case is weight. Combined the stock props performance is ok but certainly not face melting. I do have some ideas to improve on that though...
I think if you were looking to tinker, a lighter frame and the props as above would make this truly exceptional. I have some of the Gemfan Flash 3052 props on the way and think this will really improve things. Keep an eye out in my tips and tricks section as I'll review these more agressive props when they arrive.
The Furibee X140 is exclusive to Gearbest and at the time of writing is exceptionally good value at $105 for the model without the receiver or $113 with a frsky/flysky receiver:
The Furibee X140 is a traditional style 3 inch quadcopter as opposed to a lightweight 3 inch like the Leader 120. It is available as a Plug N Play (PNP) with no receiver or as a Bind N Fly (BNF) with either a flysky receiver, frsky receiver or futaba receiver.
Some of the key features of this quad are:
The box it came in is small brown and very boring which is good because on a budget quad I don't want to be wasting my money on that. What I am most happy about are the components:
FPV: Micro CCD and switchable VTX
They key points for me is that this has a real CCD camera (Furibee micro) and a vtx that is switchable between 25mW and 150mW. I'll cut to the chase and say the camera is excellent and like the HGLRC elf which also appears to be a clone of the micro swift, you would not be able to tell the difference. Combined with the VTX this 'hits' the right FPV feed where other micros miss.
Frame: Good luck trying to break this one.
Straight up the frame is a tank. It uses separate 4mm thick double chamfered replaceable indicular arms and is incredibly stiff. It has been designed in the streched - x style (less space between left and right motors than front and rear) which gives better pitch fine control and less turbulent air to the rear props in forward flight. One challenge with the streched X is that props are in full view in FPV (like the floss 2 frame) but a taller set of standoffs and camera mounts elevates the camera mostly above the prop disc line making for a nice FPV view. It is not a light fram however because of this but is crazy durable. I don't doubt gearbest will be listing arms soon but don't think they will be selling many...
Electronics: Well balanced
Really glad they went with 20mm x 20mm here, I really think this is the way of the future. I'm even trialling a 20mm x 20mm stack in my 5" race build here. Flight controller is an Omnibus F3 with betaflight OSD, a proven unit. ESC is 20a which will have no problem on this quad even if you put much bigger motors on. Best part is that it is 4s capable. Also it is nice they included a real buzzer/led combo. Buzzer is handy but not vital now that we have the motor buzzer on betaflight 3.2.0 and up. Leds are nice and connected to the DIN so there is are limitless options for how you wish for these to light up. Nice to have but in truth I'll probably remove to try save some weight (4g for this unit).
Motors: Efficient but need a 4s battery
It's a good thing that the ESC can do 4s because I feel a 4s battery is really needed since the motors are of a fairly low kV (3100kV) They should however offer excellent flight time (update in part 2 review: they do). For the record they are Ready to Sky branded 1306 3100kV motors that appear to have smooth bearings and no obvious visual defects.
Propellers: Easy upgrade here
The props included are 4-bladed 3030 meaning they are 3.0inch with a 30° pitch. This is a fairly low pitch, ESPECIALLY for the 3100kV motors. They will get you flying but when you get replacement I would definitely go for something more aggressive like the excellent Gemfan Flash 3052. I think this will be an excellent upgrade and will make a 3s battery more relevant.
Weight: Bit of a tank
This is not a light quad at 125g dry (no battery). By comparison the Leader 120 was 64g but this is a different class of micro with bigger motors, much more durable frame and superior FPV camera/vtx. In addition it will lug a 4s battery unlike the leader which is 2s or 3s at a stretch. I'd expect this to be more "chuckable" than the leader which has more "floaty" flight characteristics.
Betaflight 3.1.7 came sock on this flight controller. After looking through the settings it was dead stock without even an arm switch set up. Rather than setting up and flying on 3.1.7 I jumped straight to 3.2.1 which is the latest release at time of writing. It is a step change improvement - in particular dynamic filters. Below is a gallery of screens where I changed setting from stock. Clich through and see the captions to help with your own setup.
Early pre-flight conclusions
I really like the components on this one especially at the price point ($105 currently for PNP on the discounts page). I think it was unecessary to build the frame with removable arms and heavy 4mm thick ones at that. Micro quads tend to be more crash resistant because they are lighter so this looks like an overkill. In saying that it should be VERY VERY durable and should offer good flight times with the more effcient low kV motors it has. I'll comment after part 2 of this review on mods but I have a few in mind that should really make this move.
Link to the different versions:
Furibee X140 no receiver
Furibee X140 flysky receiver
Furibee X140 frsky receiver
Furibee X140 futaba receiver
In part 1 of this build we looked at the JJRC H36 quad and LST All In One (AIO) camera/VTX to make a budget yet powerful tiny whoop. One of the limitations of this build is the small remote that, although proportional has poor fine control due to size and low quality 'gimbals'. In part 2 I'll turn this from a toy quad to a hobby quad with the addition of the Furibee F3 flight controller which will allow you to use your proper transmitter (Frsky, DSM or Flysky) and have the full control of betaflight.
The advantage of running a full size remote is for better finger control. The advantage of running a betaflight flight control system is absolute control over all flight functions - angle, horizontal, acro modes, multiple rates set to switches and the least sexy but probably key is a proper failsafe system to prevent fly-aways
First a word of warning. The Flysky version of this board only supports AFDHS and not AFDHS 2a. This means you cannot use the Turnigy evolution nor the FS/TGY-i6s. I made this mistake and so have had to add the RX2a pro receiver which thankfully there are at least pads for. Bad news is that this adds about $6 in cost and 0.8g in weight but the good news is I now have the faster speed and failsafe of an ibus rather than PPM system. For those using FRsky this does support RSSI and VBAT over telemetry.
Physical install is simple and probably best described by the pics below with captions. Unfortunately I couldn't keep the sound module as only the speaker is external - the music source is integrated in the stock flight controller. Click to embiggen the pictures and see commentary
In terms of setup in betaflight, I updated to the latest version of betaflight (3.2.1 at time of writing) and captured a few screenshots below where I made changes, particularly because I had never before set up betaflight with brushed motors - there are some specific differences.
So how does it fly? The standard flight control will no doubt get you off the ground with a respectable ability to buzz around but the being able to use your own remote and run with all the options of betaflight it is like a whole new quad. It feels more agile and surprisingly much faster - probably because you have complete control over all angles. To be fair though acro is challenging indoors and I tend to stick with angle or horizon mode but with a greater maximum angle. Good news is on a still day this can easily be flown outdoors and since it has a decent reciever can get very good range.
Flight time on the stock battery is around 4-5 minutes on the stock battery which is actually pretty awesome compared to the 2-3 minutes you get on the 6mm motor whoops. I think this is because the 7mm motors hit a sweet spot in efficiency that allows the larger 260mah battery. I don't really feel agility is significantly compromised either - especially with the extra power and flight time that is gained. That is because these larger motors spend less proportion of energy just getting the quad and FPV gear (and santa!) off the ground leaving more in reserve for actual flight and manouvers.
Will it powerloop? No, that is more the realm of micro brushless but I'm still yet to see and indoor flyer that is as practical and safe as the ducted whoop style.
My final conclusion is that the JJRC santa quad and LST AIO camera is a lot of fun on it's own but for the extra $20 or so for the furibee flight controller, it really comes alive.
Final note: It is possible to bind a taranis or flysky remote directly to the stock flight controller using a multiprotocol module. These can be more expensive and fiddly than a betaflight flight controller however they can be used with multiple toy models. Futhermore the stock flight controller can actually be 'hacked' to insert dual more angle/acro software but some basic hardware and software fiddling is required. I'd recommend googling silverxxx acro firmware, notfastenuf and CaninoRC for more details, particularly on RCGroups, Micro Motor Community and Youtube. Some great resources put together by talented people if you are willing to put the time in to implement.
Time for a cheap, high performing tiny whoop build with a twist - Christmas style. I know it is a novelty but the JJRC H67 Flying Santa Claus RC Quadcopter is actually the Eachine E011 in disguise. The E011 in my mind is the absolute best starting poing for a tiny whoop with the larger 716 motors that have absolutely no problem lifting an All In One (AIO) camera. So what make this build so special? Freakin' Santa Claus does!
The JJRC drone is in Christmas themed colours and comes with a Santa minifig. The best (and most annoying part as a parent) is the noisy sound module on board that plays a Christmas tune. As a stand alone unit this is a micro brushed quad that flies very well albeit with a small but proportional remote. Of particular note, the motors and battery are very good and will give you a genuine 5 minutes of throttle-heavy flight time. Included in this pack is:
This quad is a lot of fun but it needs more FPV! I used the LST - S2 5.8G 800TVL HD Micro CMOS FPV Camera which is tiny and weighs only 3.5g. I've built an E011 whoop before with a 5g AIO Eachine TX01 camera and it had no problem lifting that. This new LST camera will offer much better performance even the seemingly small 1.5g weight difference has a very big performance impact on these brushed whoops.
See below for pictorial instructions for mounting the camera in the spirit of Christmas. The minifig is very heavy at 4g but I couldn't leave santa out of this garish whoop so will take him off when we start taking the Christmas decorations down, weight savings will have to wait for now.
Here is a handy tip given the crappy stock reciever range. Drill a 2mm hole on the canopy as shown above and poke the antenna through it. You get over 100% more range which is absolutely necessary as this does not have a failsafe and will fly away from you if you lose signal!
In conclusion this is an absolute bargain for a basic little FPV rig. To date all of cheaper fpv ready whoops have the smaller and less powerful 6mm motors and I'm suprised that a 7mm motors FPV ready unit hasn't been released. No problem though, as you can see above building this is not difficult or expensive and much more rewarding. The set up as above flies well enough but needs quite a bit of throttle. When you decide to take the minifig, canopy and speaker out you'll find performance will increase dramatically but that can wait till after the novelty has worn off :)
If you want to use your own hobby-grade transmitter and have the full control of betaflight with acro/air mode, check out part 2: Adding the Furibee F3 Flight Controller. I'll have a link live here by 4 November.
Parts in this build:
See this page for current bargains on Gearbest for play and racing