Last night, I hooked up all of the RC gear in this kit to test it all out before it goes into the model. I ran into a couple of problems, but found fixes for both (I think):

1st problem: I hooked up all of the wires (J1-J4) to the receiver the way that Tamiya told me to do it....J1 = CH1, J2 = CH2, J3 = CH3, J4 = CH4. However, instead of the right stick (up and down) controlling the gun elevation servo, I noticed that the left stick (up and down) was controlling the servo. To see what the right stick (up and down) was actually controlling, I hooked up the gear box, and sure enough, the right stick was actually forward and reverse....so the left and right sticks were reversed as far as the up and down control went. Its like channels 2 and 3 were reversed. Channels 1 and 4 were doing what they were supposed to do, so everything wasnt reveresed, just the up and down controls on each stick. Im not sure why this is. The instruction book for my transmitter mentions something about Mode 1 and Mode 2 reversing these channels, but I see no way to control which Mode the transmitter is in. I have a Futaba 4WD Attack Radio.

To fix this, I switched plugs J2 and J3, meaning that J2 is now plugged into channel 3 on the receiver, and J3 is plugged into channel 2 on the receiver. Everything that I tested last night now works as it should. I just hope that switching these two channels on the receiver doesnt mess anything else up.

The 2nd problem that I had was with steering. I have seen a few other people mention that they had this problem in other threads, but not sure if they fixed it or not. Here is what I found last night. I kept the motors plugged into the power, and opened the gear box. I had a friend hold everything in the gear box in place while I applied light power to the steering motor through the RC transmitter. I set the gear on the steering motor to the length that Tamiya tells you to do, and that is what caused the problem. The allen screw that holds this gear to the motor does not fully recess into the gear, and with this set at the distance that Tamiya gives in the instructions, the screw actually engages the steering gear in the gear box, and binds it, causing the motor to do nothing. I tested this at a few different distances, but in the end found that I had to put the gear on the steering motor almost all the way back on the shaft before it would clear the gear that it engages in the gear box.

Once that adjustment was made, the steering worked really smoothly.

I hope this helps some that may be having the same problems that I am seeing

What model receiver is it? R124H or R114H?

Mode switching is nothing more than swapping the J-connectors to the receiver, I believe. When I put the 4-channel FM radio in the KT, I actually had to hook up servos to the receiver to figure out what stick went to what spot on the receiver. I then mapped them out on a sheet of paper.

Just out of curiosity, is the set screw on the flat portion of the motor shaft? Or does it stick out, even with it over the flat area?

The set screw does stick out past the smaller diameter part of the gear. However, when you mount the gear, did you measure the 14mm distance from the motor face, or from the white plastic plate?

I checked mine. The gear engages only with the larger diameter portion of it. If measured from the white plastic motor mount, it looks like the gear would engage with the smaler portion and the set screw.

I believe you are correct. Im pretty sure I measured after the plastic piece was installed. Oops

Anyway, it works great now

No problem. I hate second guessing myself. Oh well. It needed more grease, anyway.

If you have the R124H receiver, you must hook up the connections J1-J4 in the numbered 1-4 receptacles on the receiver even though it looks backwards from the manual (the receiver has them 4-1 from the top down).

I still haven't figured out why mine reloads the main gun backwards after firing it. Instead of raising the main gun, it lowers it! [sm=lol.gif]

Edit: Actually it's working right. The op manual says that after firing, no matter where the main gun is, it goes to +5 deg then back to it's original position. Like a built in elevation uncouple for the loader. I was thinking it just elevated, then went to it's original position. [8D]

Sorry I didnt make that channel part clear. What I mean is, if I have J2 connected to channel 2, and J3 connected to channel 3, the vertical movement on my left and right sticks are reversed. In other words, the vertical right stick SHOULD raise and lower the gun, and the vertical left stick SHOULD be the throttle/reverse. Connected the way they should be, the right stick is throttle, and the left stick is the gun up/down. If I plug J2 into channel 3, and J3 into channel 2, it works the way it should.

According to the instruction manual for the radio, this looks like what they describe as "Mode 2". The only problem is, I dont know how to switch the "modes" on the radio..there is no physical switch to do that with.

Not sure about the mode switching thing. What receiver is it?

Have you tried resetting the DMD (from the ops manual) and doing the setup for the radio again (step 46 in the assembly manual)?

Not sure where the heck the attachments came from. Disregard.

Its a Futaba 4WD Attack.

Ive tried the setup on the DMD 5 or 6 different times with the same results.

Im OK with the setup like it is, unless it would eventually cause problems somwhere else.

Guys...

Japan's 'mode' preference is the reverse of ours. I guess its another of those northern/southern hemisphere reversal hings, eh?

For switching between Mode One and Two, most lower-end or suface radios don't have a switch, as it was meant for aircraft models to swap funcions according to flier preference. Check out the Futaba SkySport manual for more data.

For the 4VWD and 4VF, you have to swap the modes by swapping the channels manually. It has NOTHING to do with the DMD, and when setting up the DMD for stick throws, you can push them in ANY sequence. All the DMD is looking or is the throw limits... ie. what it is to interpret as 100% stick throw.

Thats how Willy's '80% throw cheat' works: the DM thinks 80% stick is actually 100%, and when you use 100% stick, the DMD thinks the trim has been toggled. But many of us are just going the fancy route and adding the gun triggers, so this is irrelevant.

Be nice if Futaba would sell a 'Tamiya Tank Trigger' package... thn again, if we got our wishes, we'd have a few more tank models out now, eh?

you can plug things anyway you want into the receiver. just rerun setup after making changes.
I drive with my right and fight with my left (T-Rotation and elevation main gun is on a seperate button). But there are others in my club who do it the otherway. and I have seen weirder setups where forward/reverse and turret rotation is on the left while elevation and tank rotation is on the right. Does not matter as long as you practice and get good with your setup.

Regards,
James

I figured as much about "modes".

One setup I don't like is steering and throttle on one stick. Maybe because of running the KT for so long with just the 2 channel radio. I actually tried running the Leo on one stick and it looked like the driver was going to get duct taped to the gun tube and go for a little "ride"!.

One thing I don't like about the Leo is the setup when driving in reverse. If I move forward and want to go right, I hold right stick. If I want to go backwards and right, I should still hold the right stick. WRONG! You have to hold left stick. But then, the TC is facing backwards, so his right is my left. RIGHT? NO! You are looking through a camera in reverse, dummy. [sm=spinnyeyes.gif]

Just gonna' take some getting used to.