soulfly

Hi there guys,

First of all, great forum! I have been an avid reader over the last few weeks while selecting an electric heli, finally choosing the jabo 2.

Yesterday with my first attempt with the heli, things went well with no crashes, although I didn't manage to get airborne for very long before landing again (due to fear of crashing the heli or smashing up furniture!)

Today I decided to be a little more adventerous and go for a 2 foot hover. Whilst doing this I managed to hit the heli into a wall (DOH!). After sitting it back up i realised that when the rotors are spinning after applying no throttle, when they finally stop they fold up and slump down to one side - is this normal?? I don't recall it doing it on the first days flying attempts...

Second Question:-

After deciding it was a better idea to practice outdoors with more space, I was flying in the garden with a shaky hover attempt - I was losing control a Little so tried to sit her down but the heli didn't respond! I ended up crashing into a garden wall due to the heli's lack of response! Any ideas why the heli would not respond? I was only about 15-20ft from it at the time, I thought it must have a better range than this!!

Any help would be much appreciated (sorry about the long post!)

Thanks

J-a-s-o-n

You can tighten up the screws that hold the main blades on but don't over tighten. You don't want them so tight that they can't balance out when rotating. Mine do the same. As for the slow response, all I can say is to make sure your batteries are fully charged. Hope this helps a little.

JohnY2004

Check the batteries on your transmitter, and make sure it stays above 9 volts.

soulfly

I've just been reading some other posts and it seems the position of the receiver ariel can make a difference. Mine is sort of wound up in the middle, total length (while wound) just short of the tail rotor and it just hangs from the heli. This is how it came out of the box. Is this right or is there a better way to do things??

Thanks

J-a-s-o-n

I have mine wrapped around the skids on one side of the heli. That way it won't catch on an obstacle. I found out that if it is tied to the tail boom it will cause problems like slow or sudden responce because of interference from the wires that power the tail motor.

soulfly

hmm.. so is it better to wrap it round a skid rather than let it hang? I wasn't sure if coiling it might some how have some negative affect on the signal range

UKgroucho

Best reception is likely to be when the whole antenna is 'unfurled' - but they'tre typically pretty long. you might want to route it along the frame / landing struts (stick it on with cellotape) and have it 'hang' somehwre that will to make it harder for it to be pulled into the main gear - and leave some 'slack' in it if yo do tape it onto the struts... if they come off in a bad crash you don't want the antenna to get plucked out of the RX.

I'm still progressing along the learning curve with my Aerohawk. I made teh mistake of trying to get 'fancy' with my antennal. Wound it around a short drinking straw, put heat wrap over it and glued in onto the back of the airframe so it ran alongside the tail boom (but not in contact with it). This mean that with the 'body' on teh heli no antenna was visible .. After much trial and error (and crashes) I realized that reception sucked. I think there is probably some interference from the tail motor power cables that run up the inside of the tail boom. Anyway the big lesson here is to do a signal strength test ... try one now and then test again when you make any mods that affect the antenna. You need enough space (obviously).. what I did was put the Aerohawk on a table on our deck and walked off down the garden whilst making small control chages (enough throttle to have the main blades spinning but not taking off). You can see if the main blades follow your control movements - and you can play with the tail motor also and see that it does as you expect.

Relatively crude but enough to show me that I was getting glitching - and it went away when I unfurled the antenna...

J-a-s-o-n

I haven't had any problems with it.

soulfly

Thanks for the help guys, I think this may have helped solve my problems .I'll let you know tomorrow in day 3 of my Heli adventure!

BTW I notice a few UK guys replying to this post - where do you get your spares from? I'm sure it'll not be long before some sort of spare part or upgrade is required and I don't fancy waiting a week or so for it to come from Hong Kong (unless of course the price is really good) I anticipate needing some spare tail motors, and I think some heatsinks may be a good idea, although maybe not needed for the stock motor?

JohnY2004

The current antenna of jabo2 has been trimmed at certain length and with certain impedance to match the source impedance of RX for maximum power reception. Coiling the RX antenna is a bad idea because the coiled wire of antenna introduces leakage inductance, distributed capacitance, and parasitic effecting the impedance matching between the antenna and the RX. With mismatched impedance between the antenna and RX circuit, maximum power reception would suffer. It's better to leave the antenna alone.

justin_92_92

My Feedback: (2)

wow....thats in depth. . lol hope you do well with the jabo...its a very great bird...

JohnY2004

I was flying my helicopter in the backyard this evening at about 5 ft height and a sudden gust of wind lifted it up to 8 or 10 ft and crashed into a tree. It broke a paddle rod by 1/2". Then I decided to cut the other side of a paddle rod by 1/2" to make both sides with equal length. Then went back to the back yard and tested my heli. I was surprised to find out, with a shorter paddle rod, the helicopter had became more stable in hovering. It seemed a few seconds of delay before the helicopter responses to the radio inputs and the servos over correcting or undercorrecting problems have disappeared.

Mr.Tango

Hi gents,

The method of doing the radio range check described above is the norm with the fixed wing R/C boys and this is how I check out my plans, so although being described as being low tech, this is the norm. On a good day you may get around 40 meters away with the transmitter aerial in it's shortest.

Shortening the flybar has the effect of reducing the airflow as the paddles are not spinning so fast and therefore not having as much effect. This will, I would think reduce giro stability to a point, but if your happy then leave it. However, if you do increase the size of the flybar and the control problems return why not reduce the the control thows, do you have dual rates on the transmitter?

JohnY2004

Since the servos don’t response to control inputs with precision, either with too little stick input, the heli doesn’t response or with slightly push of the stick would provide too much stick input causing the heli becomes unstable and hard to control. By shortening the paddle rod, it reduces the airflow slightly over the paddles in exchange for better input control precision.

JohnY2004

I used the trainning gear rod and cut it 2cm longer than the stock paddle bar. With longer paddle bar, the helicopter becomes even more unstable, swinging left and right, back and forth like a spinning pendulum and lacks of responsiveness until it's too late. Broke one blade and lesson is learned from this experiment. Now I'm convinced that with shorter paddle bar helps improving responsiveness from the helicopter and cut down $$ for blades.