Problem with servos

bitternboy · Post by **bitternboy** » Sun Aug 09, 2009 8:14 pm

Hi. The components of my robot are together but when assembled do not react when the control sticks on the controller are moved. The crystals definately match and it is clear that the receiver and the transmitter are connected because the servos stop spazing when the transmitter is turned on and start jittering the moments it's turned on. Any suggestions why this might be?

bitternboy · Post by **bitternboy** » Sun Aug 09, 2009 8:20 pm

P.S I am going on holiday 2morrow and won't be back 4 a while so if I don't post a reply it's not because i'm not grateful of your advice.

Flippt · Post by **Flippt** » Sun Aug 09, 2009 10:49 pm

Are the crystals matching in brand? Some actually mistakes that all brands work with eachother.
Interference could come from anywhere. Change room or so to see if that elimnates it.
Check the battery, it could be discharged. Both in bot and transmitter.
Do you have electronics/motors near the arial or reciver. If yes, try moving it away.
In worst case, the reciever is broken.

Ps. There is a button called edit, use it in future posting!

Team Terror · Post by **Team Terror** » Mon Aug 10, 2009 8:41 am

Also try to keep your robot as far away from other electrical components as possible, my ants get interference from my computer if they get too close. Metal can also interfere with your radio signals.

bitternboy · Post by **bitternboy** » Mon Aug 10, 2009 9:45 am

The crystals definatly match.

peterwaller · Post by **peterwaller** » Mon Aug 10, 2009 10:03 am

When you say the crystals match it is not just about both crystals being marked with the same frequency or about both crystals being the same make it is about the Rx crystal matching the receiver. All transmitter crystals are made the same ie to the frequency marked on them but receiver crystals are made to a slightly different frequency. This frequency is the transmitter frequency offset by what is called the IF or intermediate frequency and different make use different IF frequencies and therefore different offsets. The main ones I know of are hitec and futaba so it is best always to make sure the Rx crystal is the same make or if they don't make crystals at least a make recomended by the receiver manufacturer.

Post by **BeligerAnt** » Mon Aug 10, 2009 7:22 pm

I?ll try with the most obvious points first:

Are the servos plugged into the correct channels of the receiver?
Is the receiver battery fully charged? A flat(ish) battery can cause all sorts of problems!
Is the transmitter battery fully charged?
Are the crystals properly plugged in?
Does one servo work on its own?
Are the servos modified for continuous rotation?

Also, can you try swapping any components? e.g. try a different pair of crystals, different transmitter, different receiver, different batteries, different servos.
I realise this is not always easy when you are just starting out.

If the parts came from a traditional high street model shop and have not been modified, you could try taking them back if you are still stuck. It is possible (although unlikely) that one of the parts is faulty.

Post by **petec** » Mon Aug 10, 2009 9:57 pm

Crystals match, but are you sure they are plugged in the right way around? (I mean the transmitter crystal is in the transmitter and the receiver in the receiver)...obvious, but easy to plug in the wrong way.

bitternboy · Post by **bitternboy** » Thu Aug 20, 2009 1:17 pm

Thankyou. The problem turned out to be the make of the crystal not matchin up 2 the transmitter and reciever, thanx to anyone who commented and unless I have any serious problems I will be at the reading robot club in october.

thanx again and parralax, the robot will be awesome.