Wrong Radio?

[Rick.K]

New to RC trucks. Building a Knight Hauler. Bought the Tactic 404 TTX as part of the Tower Hobby combo pack.

Transmitter has one self-centering lever on right (acts as throttle and steering), and non-centering on left (horn and gear shifting). Only the left-side lever has a trim slider under it.

The motor, sounds, and servos work, but I don't see how I can access all of the MFU's features with this radio.

Suggestions? If I need to return this radio (I'm guessing the 404 TTX is ok to use unless you have the MFU), what radio should I get?

[Kingcam2]

Hi Rick

Do yourself a favor and don't do what i did, don't get a Hitec Optic 6 sport 2.4ghz.

This was my first radio and I have found it not suitable for beginners who have had nothing to do with Rc before,

I have have had it for little over a year now and only know how to do 3 thing in the menu.

If I was you I would get a Turnigy 9X 9Ch Transmitter, Hobbyking.com have them for $60 Us.

Regards Cameron

[mavrick0]

I know you are going to want to stay with tower so you can get the payment plan and if that's the case then you'll want this radio: http://www3.towerhobbies.com/cgi-bin...&I=LXEDMK&P=ML
I'm sure it's a lot more pricey then what you bought but it is designed for the semi's with all sticks self centering and analog trims. This will be your simplest and easiest choice.

With the radio you have that doesn't have analog trims you will have issues doing certain MFU functions also with the way you have your sticks setup will cause you issues as well since the left stick should be throttle and shifting and right should be steering and horn.

[Rick.K]

Hi Maverick:

This morning I went to the Tower site and located the Tamiya Attack radio. Since I am new to this hobby and this radio is designed specifically for the Tamiya trucks, I ordered one. Since I took the Tactic radio out of the box and set it up, I'll have to check to see if I can repackage it and return it for refund.

Right now I'm trying to figure out if I can buy or make the gear shift gate and the steering gate to install on the transmitter. At least the gear shift gate to protect the transmission.

I found a good article on line from the Tamiya Club that explains how to set the radio up, adjust the steering and shift servos, and explained how the gear shifting itself works.

I hadn't realized that the trasnmission is 'held in gear' by the operator (kept wondering while watching the spring loaded left stick on the Tactic center and move the shift servo to center, or second gear. It's starting to make more sense.

There is a lot to learn in this hobby, starting during the build, and I'm enjoying the effort and the help from folks on this site!

[mavrick0]

I'm not 100% sure if the Tamiya radio comes with the shift gate or not. I know the Futaba version does come with one and the Tamiya is just a rebadge version.

Another thing you are going to have to watch is if you aren't using futaba (or rebadged)servo's and have to reverse a servo for it to work that will cause issues as well for having things work according to the manual.

[Rick.K]

The instruction manual for the Tamiya Attack states that it includes a shift gate, and the kit for the mechanical support legs for the trailer is supposed to have a gate for the right side of the controller.

The Attack radio has switches on it that permit the servos to be reversed. The radio comes with a receiver.

Tower said that it will arrive on Thursday via UPS, so I can go back to sorting out the electronics in time for the holiday weekend.

I was surprised to find that the instructions for the Knight Hauler call for using self-tapping screws when installing the cams on trhe servos. I bought the Hitec HS-645MG's for the steering and shifting. The way the cams are installed the original screw was long enough for the steering servo, but not the shift servo.

I shortened the 2.6mm self-tapping screw so that I could use it to install the cam on the shift servo.

[mavrick0]

The radio might have reversing switches on them but keep in mind that means all the functions that are controlled by the MFU will be reversed as well if you have to reverse the servo's to work properly.

The reason the knight hauler calls for self taping is the standard S3003 futaba servo that Tamiya recommends is a plastic gear servo where your Hitec's are metal geared. That's why there is a difference.

[Rick.K]

The Tamiya Attack 2.4 ghz T/R arrived last night. Have not had a chance to try it yet. The instructions for the radio do not state what type of battery the included receiver uses (the instructions for the radio do not mention the receiver at all). I was surprised to see how small that receiver is (battery included inside?).

It made me wonder why the Tactic TTX 404 receiver uses a four "AA" cell battery pack to power it.

I was disappointed that the Tamiya radio did not include the shifter gate. Then I opened the box for the motorized leg support that is supposed to include the steering gate, and it was not there either. I can try to make my own. Where can I get the shift and steering gates for the Attack radio if I can make good accurate ones?

[CustomRCmodels]

Originally Posted by Rick.K

The Tamiya Attack 2.4 ghz T/R arrived last night. Have not had a chance to try it yet. The instructions for the radio do not state what type of battery the included receiver uses (the instructions for the radio do not mention the receiver at all). I was surprised to see how small that receiver is (battery included inside?).

It made me wonder why the Tactic TTX 404 receiver uses a four "AA" cell battery pack to power it.

I was disappointed that the Tamiya radio did not include the shifter gate. Then I opened the box for the motorized leg support that is supposed to include the steering gate, and it was not there either. I can try to make my own. Where can I get the shift and steering gates for the Attack radio if I can make good accurate ones?

all receivers need a power-source of 5Volt to operate . Therefore the deal with the 4xAA battery packs .
The Tamiya Attack needs that too :

REQUIREMENTS
AA Batteries: Four for transmitter
Receiver Battery: 4.8-6.0V battery pack (do not use dry-cell
batteries as receiver's power source)

but in your case by using the Tamiya MFU , you don't need no extra power on the receiver , since the MFU supplies power to the receiver.

If you would use this radio-system with any other truck , boat or any type of vehicle , which uses a ESC ( electronic speed controller ) and it is one of them which has a BEC ( battery eliminator circuit ) , then you will not need extra power to the receiver either.

since you are new to all of this , you may want to look at these 2 webpages
( even thought I have that posted in my tanker-section , it also applies to the truckers ) ,
explanation about stick modes and other radio system terms :

http://customrcmodels.com/Tanks/id92.htm

http://customrcmodels.com/Tanks/id79.htm

don't get too confused with these info's , but again , some of that stuff listed there applies to the trucks as well .

[Rick.K]

Since the Tamiya receiver has only four connections, and they are all for servos, how is power passed to the receiver?

[ricm]

the servo cables have 3 wires. In the case of Futaba you have:

red = +ve supply
black = -ve
white = signal from receiver

when everything is plugged in, the red wires all end up being interconnected through the receiver, same for the black wires, so the receiver and servos all share a common power connections. Your receiver will get its power from the MFU through the red and black wire(s) of J4, J5, J6 and/ or J7. The white wire of each of these leads carries the control signal in the opposite direction, from the receiver to the MFU. If you didn't have the MFU, one of your 'servos' would be the ESC so the receiver would get power through the red/ black leads from that instead.

If you have the MFU, don't bother with the steering gate. The MFU default mode de-activates the shifter servo in preference for the horn, and its useful to have the horn function whilst steering also. You just need to remember to de-activate the coupler mode (ie. return to horn mode) after you connect/ disconnect the trailer, then there's no chance of the trail de-coupling anyway. I took my steering gate off after my first run and I've never used it since.

If you contact Futaba directly and ask them really nicely, they should send you a shift gate free of charge.....they sent one to me in Australia from USA at no cost after my original one had dropped off and I lost it ;-) I believe the Tamiya Attack unit uses the same stick bezels as the original Futaba Attack 4VWD radio, so the Futaba shift gate should fit. In any case, it shouldn't cost you anything to try.

If you are still stuck, I have spare Futaba shift and steering gates but it'll cost me $12 to ship them to you.

[Rick.K]

RICM

Excellent explanation of how the receiver works, thanks so much. I'll contact Futaba as you suggested to see if they will provide the shift gate. If I have no luck then perhaps I can mail the postage cost to you, or better send a self-addressed envelope with postage prepaid.

Gotta love a global hobby!

[ricm]

no problem.

So you are right in that if you did plug nothing but servos into your receiver, then there is no power.....! The ESC/ MFU is the key....

FYI, in my post above I said 'The MFU default mode de-activates the shifter servo in preference for the horn'...I meant to say that the default mode de-activates the coupler servo. But I figure you worked that out anyway.

I can see you don't have enough posts to PM me, so post back here if you need the shifter gate. I'll keep a look out for updates over the next week or so. I am in Australia, so USD no good for me...but I can accept paypal if that works. We can worry about that if Futaba can't send you one!

[Rick.K]

RICM

I'll give Futaba a try on Tuesday, and post their reply here.

[mavrick0]

Also if you look at ebay they are all over there.

Like this one: http://www.ebay.com/itm/STICK-SHIFT-...item4aca562686

[ricm]

yep - eBay also an option but try Futaba first to see if you can blag it for free

[ricm]

Originally Posted by Rick.K

RICM

I'll give Futaba a try on Tuesday, and post their reply here.

how did you go with Futaba? If you tried email and they haven't replied, give them a call - I found them really helpful on the phone

[Rick.K]

Tried there phone number this morning and got a Fax machine. Got busy at work and didn't have time to try again later. Will try tomorrow. I did email their customer support this evening.

[ricm]

from their website:

Tech Support

Welcome to Futaba technical support. Our goal is to resolve your particular issue as efficiently as possible.

If you need technical support or have any question, you can reach us by one of the following means. When contacting us, please include the product you are referring to, its stock number and as much information about your question or issue as possible.

Email: Email us at support@futaba-rc.com. Please try to include as much information as possible when asking your question. Also please be sure to list your full email address (ex: johndoe@aol.com) as well as at least one other means of daytime contact in your email.

Telephone: 1-217-398-8970 extension 2. Available Monday-Friday, 8am-5pm U.S. Central Time.

You might not have got thru if you are in a different time zone? They have a different number for the fax machine