Rc control

[gamefreak]

Well i have a robot competetion coming up in 2 months and i want to try to win, but i have 5 minutes to gather 15 items and i dont know a thing about RC.

Do i need to program anything or is it as simple as plugging the servos in and matching the crystals?

[Admin]

got you covered
http://www.societyofrobots.com/remote_control_robot.shtml

its all simple plug-n-play really, no programming needed, and you can buy it all as one complete ~$100 to ~$150 kit

[gamefreak]

lol, thanks but unfortunatly all this budget is out of my pockets because im the only one who knows anythign about robots in my school and i dont think the TSA club( The club the robot is for) will give me that kind of money since its a free ride(except food) to state and free to nationals if i get 1st.

Now all i have to figure out is an arm and buy 2 sets of transmitters/receivers since 1 person controls robot and other controls collection device.

I was looking at the: GWS GWT-4A 75Mhz FM System;http://www.robotmarketplace.com/marketplace_rc_radioGWT4A.html
And its daul Axis, but what does that mean? And how does that work wiht a 4 channel receiver?
Also is there a maneul that tells me which channels go to which stick?

[Admin]

consider it a long term investment towards your education

plus since you bought it, you can keep it for all future robots you build. ive always found it invaluable to test new robots using RC stuff, so its good to have.

its daul Axis, but what does that mean? And how does that work wiht a 4 channel receiver?

simply means the joystick moves in both the X and Y direction - two channels per joystick.

Also is there a maneul that tells me which channels go to which stick?

it will be obvious when you plug stuff in
i usually just guess which wire goes where until the proper servo is actuated by the proper joystick command . . . wouldnt take you more than 2 or 3 minutes . . .

[gamefreak]

Well unforunatly it requires 2 people for the bot(stupid regulations) one moves the bot while the other controls the collection device, but if each joystick controls 2 directions then couldnt i just use 2 remotes and 1 receiver and just only control one stick each?

[Admin]

if each joystick controls 2 directions then couldnt i just use 2 remotes and 1 receiver and just only control one stick each?

well, if one person just controls channels 1 and 2, and the other person only 3 and 4, then yes, you only need one receiver

[gamefreak]

If i bought an RC controller made for aircrafts, and put a ground crystal in it, would it still work? I would think so but sometimes thigns are blocked like that.

[Admin]

hmmmm im not actually sure . . . i heard you cant . . . but from an unreliable source . . . my google-fu failed . . .

im guessing its because the electronics cant handle the large difference between air and ground frequencies . . .

a good bet would be to just call up a company selling them and ask.

the problem is that the companies that make and sell the RC controllers and servos still think the buyers want them for RC aircraft and are clueless that most are actually for robotics . . .

[gamefreak]

thats sorta sad that the big companies cant figure that out.

Also the reason i asked is because since my budget is low i went to ebay, great deals, but they are almost all RC aircraft controllers, and the one im looking at doesnt tell me the channel/frequency/ or if the crystal is interchangable for ground or air

Got to keep looking 

[Dosbomber]

Taken from the Futaba FAQ:

Information on changing bands from 72 to 75, and others.
IF YOUR RADIO IS MODULAR, such as an 8U, 9C, or 9Z, then your system will work fine on ground by simply purchasing the ground module, TJ, on a ground frequency (FUTL18** with the last 2 digits being your desired ground channel) and then use it with a ground receiver.

If your radio is NOT MODULAR (uses a simple crystal to set its frequency and not a plug in frequency module in the back of the radio), then, alternatively we offer a flat rate service to change certain 72MHz air radios to ground to provide you, the modeler, more flexibility for your ground vehicle.

For a flat fee of plus $7.99 shipping:

Complete computer radio systems: $35*
Complete non-computer radio systems: $25*
Computer transmitter or module only: $20
Non-computer transmitter only: $15
7-9 Receiver only: $20*
2-6 Channel receiver only: $15
*NOTE: If your receiver is an R127DF or an R138DP the cost to convert to 75MHz is the figure shown above PLUS $44.95 to cover the cost of parts changes required in these receivers to make it function on the other band. For example, a 6X radio system sent for conversion would be $35 plus $44.95, or $79.95, to convert to ground. A R138DP alone would cost $64.95. For these 2 receivers, it is likely more logical and cost effective to purchase a new receiver on the proper band and sell the receiver you have or use it for a different purpose.

Please be sure to follow our service center instructions when sending your radio for service. Please note if you are purchasing a brand new radio, your dealer can special order this change to be done in advance prior to shipment to you.

Please also note that 50MHz, commonly known as "HAM BAND" or "6 meters" is legal for both air and ground use. If you have a HAM users license you can safely and legally utilize 50MHz frequency radios for both aircraft and ground models without requiring any changes. Only 72/75 MHZ MODULAR transmitters (ie. 8U, 9C, 9Z, NOT 4VF, 6X, etc) equipment can be converted to 50MHz and vice versa. Receivers and crystal-based (non-modular) transmitters CANNOT be changed.

Sounds like it's possible, but the transmitter has to be designed to handle it.