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Truck FAQ

My lighting set does not work correctly. some lights work some don't and I cannot set it up

When you say set up that can mean two things, Radio set up or unit set up.

For the transmitter - normally you would have the throttle and steering channel reversed (if you have a Futaba compatible tx). To set up First ensure that your ESC is working correctly i.e. going fwds and not reverse. This is easy if it has brake as in reverse it will brake first. Some then have a delay before reverse kicks in, others you have to go back to neutral and redo. Which radio set do you have?

For the Unit.
auto sets up but it does have a time out which will leave the stored settings at zero meaning that you get strange results. Every time you turn on turn the TX on first and wait till it is "ready" My spektrum takes about 10 seconds but also will run alarms for channels not set to where they should be and will not "arm" until they are set. Once it is ready then turn the RX/truck on. That should give the correct zero's. Now retry the light operation. If you still have trouble with some lights then please swap them with another slot on the controller and check whether they work there. use the plug to remove them and do not pull the wires - using the wires can break the wires! If they are still not working then send them back and I will check them out / replace them.

Setting up a Spektrum DX6 to work with an MFU

OK so this may be a little long. My Spektrum is Mode 2 so this is for that! You can reset the mode ( which sticks do what) but thats another story. Mode 2 is the one you want I think - anyway it works for me. At the end of the day it does not really matter as the first thing I did was fit the spring mod to get the left channel to centre!

First this is for the Spektrum DX6i or better. This is a 6 channel set the RX's are a tad expensive but luckily you can get cheap clones. here... there is also a twin packe ! http://www.orangerx.co.uk/product_info.php?cPath=3&products_id=45&osCsid=plqt2v0o9rblmhuhm4opg8ndl5 . On Hobbyking they are advertising a micro 4ch RX but although it binds I cannot get it to work. So cheap RX done!

Next the MFCU uses trim on channels to access extra functions. The trim on the spektrum is digital and does not go far enough and that could be a real pain. BUT the DX6i spektrum also has dual rates on 3 channels - luckily these are the ones we need - or at least two of them are. This relies on the fact that the MFCU stores the TX settings when you run setup so will accept less than 100% as the full throw, then any extra is trim ;) Never mind it works is all!

The Spektrum has 10 model memories so you can store settings for each one and you will have to set each one you want. Sounds troublesome but in the setup menu there is a copy function that will copy your settings to a new model.

First you have to reverse the channels as Futaba are always backwards and Spectrum is Futaba like.
Next enter the set up menu and scroll to the DR/expo settings. Ensrue that all the rate switches are at 0 ( the second column of the display will show 0) then navigate to the third column (should sy 100% if you have not touched it) and scroll the setting to 66%. Now set all the rate switches to 1 ( the second display col will now be all 1's) and make sure the 3 channels are at 100%.
Exit set up and set all the rate switches to 0 (66%)

Now on the MFCU press and hold the button and enter set up mode. now go through the channel set up process. left vertical from top to bottom, left stick hor from right to left , right stick vert from top to bottom , right stick horizontal from right to left. This sets all the channels max throws in the MFCU.

Thats it. On the Spektrum the left stick is vertical throttle and horizontal rudder. To eg access rev mode move the rudder rate switch to 1 and then move the left stick horizontally all the way to the left. to change between lights and legs go to the right (sticks reversed!!). This works for the aileron and elevator channels which are the right stick vert and horizontal respectively. To start/stop the engine then set the rates on rudder and aileron to 1 full right on the left stick and full up on the right.

You can set up one switch to enable all the rates in the DR/combi setting scroll through the setting from inh (individual switches work) elev, ail or rudder.

Having done that you may like to play with exponential settings - these make the the settings around the neutral point more (+) or less(-) sensitive and you can set these from -100 to +100. The one that these would be really useful for in my view is the throttle BUT the steering (aileron) may be useful in desensitising the turning circle at high speed. MAybe not!!


Setting Up Spektrum DX7/8 etc

This is to show how to access the channel positions reliably on a Spektrum DX8 but other Spektrum TX's above the 6 are I think very similar. I used the DX8 as I needed 8 channels for my heavy revovery truck, A DX7 has some 3 way switches also and the same set up should be possible. I am using OrangeRX 6 and 8 channel receivers so there is no failsafe positioning.!

I use Mode 2 but that is probably mostly not a problem. Mode 2 is throttle and rudder on the left stick Aileron and elevator on the right stick. I am sure they do this just to confuse us ground based people so from here it is just a reference to which stick and NOT a function except for the throttle which is the throttle. This set up will easily give access to the 8 selections on each channel via the standard access mode. With this sort of TX we could have more positions accesible by using the flight mode switch but that is not covered here as it is not currently available on the USM-RC2

My Receiver is connected as:
throttle = ESC and USM-RC2 Ch 1,
Aileron = steering,
Rudder = USM-RC2 Channel 4 (because this was already set up for lights
Elevator = USM-RC2 Channel 2 ( most used when running selection (e.g. horn)
Aux 1 = USM-RC2 channel 3 (little used sounds)

The TX set up to give 60 and 100 % signals depending on the position of the mix switch. So with the mix switch in position 0 we have 100% output and with it at 1 we have 60 - this can of course be varied but you need to set up the USM-RC2 throws in the proportional channels (drag the blue handle to where you want it)

In the DR/Expo menu for the Rudder and Elevator channels set the switch to MX, move the MIX switch to pos 1 and then set the D/R settings to 60. (fro both channels.)

In the mixing menu select Mix 1 set the channel (top selection) to ax1 > ax1, set the rate to +66% ( may seem strange but this is to get the mix switch used the same way). Set the SW to Mix (no offset or trim - trim should be =INH).

In the servo set up place the cursor over where it says THROTTLE (or maybe another channel) select - scroll to AUX1 and select again. in the throw settings set to 60% . now with mix in pos 0 this will give 100% throw and in pos 1 it will give 60%.

Now these 3 channels will all give 100% with mix sw in pos 0 and 60% with it in pos 1.

You can use different switches if you wish but not the gear sw as this only has 2 positions.

You should be able to easily adapt this set up for other transmitters.


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