I am new at this entire business of rc models, and I am trying to figure out how these systems work. I tried buying units like these (http://www.allelectronics.com/cgi-bin/item/RC-13/search/4-CHANNEL_ON___OFF_12_VDC_REMOTE_CONTROL_.html) to avoid using fancy gear. However, I have had no luck, they units have been not working/burning out for no reason, etc. so I am looking into actual radio equipment. I understand the science behind it, but I can't find a site that explains how you hook everything up. I need to be able to control, from say a four channel radio, two pumps and two motors (each of which must be reversible.) How is this done and how much am I looking at cost wise? I have absolutely no idea what to get, but I don't really want to spend more than ~$150 unless ABSOLUTELY required I'm in high school, so this project is taxing my resources as it is Thanks for your help!
this is one u can use i have one .it does what u are asking for.http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXEUM1**&P=0
What have you burned up (the TX or RX) and what did you do. The Vex radio you refer to is pretty darn rugged and reliable - I have literally more than a dozen in service in my club. The RX is not suitable, however - it is designed for interfacing to a microcontroller not to servos. You just replace it with a regular hobby RX (of the proper shift) and you are good to go. There is a full discussion over on the NTXBG.org knowledgebase under Vex Radios. Cheers,
Is that what these are? I don't know, I just purchased them to see if they would work to control the motors and pumps. The reversible one burnt out after 5 minutes on the correct current, the 4 channel one just refused to work.
Welcome to the fun world of warship combat! If you like trying to figure things out, you'll love it here! You now have at least $38 invested in your education; congratulations! I don't see any detailed info on the All Electronics site, just a photo & brief description. From that description, I can't 100% conclude whether each of the 4 "channels" consists of a switched 12VDC power lead and a return, or a set of "dry" (i.e. no power provided) contact leads. In a dry contact setup, the system opens or closes the contacts to open or close whatever circuit you insert them into. Since the description says that it "operates" (as opposed to "supplies" or "provides") 12VDC, up to 6A, I'd guess maybe 55%/45% that it's dry contacts. It's easy enough to tell, with the right tools. Do you have a multi-meter? If not, hot-foot it down to Radio Shack, Fry's, or whatever electronics supply store you might have nearby. You can pick up something usable for as little as $10, up to several $hundred. Consider this another investment. You'll find plenty to use it for, for many years to come. I have no idea what you may have hooked up to your receiver. Any details that you can provide about what you hooked up & how will help me (others as well) understand exactly what you're doing, what you've tried, & what might have messed up. If the unit actually supplies power (i.e. it's NOT dry contacts), then you might have connected 2 "hot" leads together, or a "hot" with a return & no load (i.e. no resistance) when it was switched on. Either condition might have exceeded the 6A rating & blown the unit out. I don't see anything in either the description or photo that suggests that any channel might be "reversable". Here's what I'd suggest: Power up both the transmitter & receiver. Set your multi-meter to measure DC volts, with a range of at least 12V. Connect each meter lead to 1 of 2 wires for a channel. The meter should read either 0V or 12V (or something pretty close to). Push the "ON" button for that channel; the value on your meter should change; if it was 0V, it should change to 12V, or vice versa, if the unit is supplying 12V instead of acting as dry contacts. Repeat the test for the remaining 3 channels. Set the meter to measure Ohms. If it has a "tone" option, use that, too. The meter should read some very high value, infinity, "OL", "----", or something else besides a regular number. This represents the "open" state, or a very high resistance (i.e. the resistance of the air between the leads). Touch the lead tips together. The meter should register a very low value, approaching 0. If you have a "tone" option turned on, you should hear a sustained "beep" while the tips are making contact. This represents the "closed" state, or no resistance (i.e. no air) between the leads. Touch each lead to one of the wire pairs from a channel. If the meter reads 0, & you hear the tone, then it means you have a closed contact. Press "OFF" for that channel, & the tone should stop/meter display a high value. Turn the channel back ON, & the tone should come back. Repeat for each channel. At the end of the day, though, this type of unit is not what you need to control a R/C ship, combat or otherwise. What you probably want to get started with (what 99.99% of everybody uses) is a hobby R/C (radio control) set. This consists of a transmitter, a receiver, & some number of servos. The transmitter has input controls, such as sticks, knobs, switches, etc. Servos plug into the receiver & make things move. The positions of the input controls on the transmitter are sent to the receiver, which in turn operates the servos to set them into positions that equate to the transmitter's inputs. Through wheels, pushrods, & other mechanical linkages, the servos operate whatever you might need moved. A rudder is a pretty obvious example of something that changes position, based on an input control such as a wheel, knob, or stick. It's also pretty common to use servos to physically operate pushbutton switches (electric) or valves (gas) to make various functions in the ship happen. Did you happen to read the article I referred to about Radio Basics? If there was anything there that wasn't clear, or didn't go far enough, let me know; I'll see if I can get it corrected. That should have enough to get you started. What will help a whole lot, though, would be to get a chance to play around with a R/C set. When you see how a servo's motion tracks directly to what you do with a stick or knob, it'll make all the sense in the world to you. JM
Oops, my bad. I saw the All Electronics tag and thought you were talking about Visit this site The one you bought is not really suitable (it is not porportional, and probably does not have the current capacity you need, thus burning up channels). The Vex TX is $29.95, but to take full advantage, you will need to spend another $30 or so on RX and extra crystals. You might just be better off with getting the new Spektrum DX6i which for $179 on sale - then you don't have to worry about frequency crystals. Cheers, Wreno
What I am looking at now is this Hitec radio: http://www.servocity.com/html/laser_4_fm_ground_systems.html For $150 for the whole package it seems to be a pretty good deal? I do have a multimeter, I tried that too. The way it works is that the entire unit had a power input, then each channel had a positive and ground wire. Still no luck. The company says they will refund them, so I am going to get the one above, hopefully that will work better?
I'd say you're on the right track, at least. Hitec is a good brand that many people consider their favorite. I've got a couple myself, & they're generally solidly-built & reliable. Ground frequency is a requirement, unless you go outside of the hobby R/C band (i.e. 2.4GHz, 50 MHz "ham" band, etc.). A low-end radio like this is ideal. No need for "computer" effects that really have everything to do with flying helis inverted, etc., & do nothing for ships except add to the cost. Even the V-tail & elevon mixers are things that you'll never need, & would be overkill if if caused the price to go up. It's getting hard to find non-computer multi-channel R/C sets anymore. You should take an inventory of what functions you're going to need to control. That will help you define the characteristics/features that you need to look for. Start with channels; the following are typical uses for individual R/C control channels: - "Throttle" (forward/reverse) - Rudder - Fire 2 (groups of) gun(s); each "throw" of the stick/other control can fire 1 gun (or group of guns), just not at once; "neutral"/center position fires nothing - Pump on/off (alternatives: run pump full-time, auto-sense water) - Rotate 1 (group of) turret(s) Depending on how much "stuff" you want to control, you can eat into the channels pretty quickly even before you've given yourself the ability to fire a shot. My favorites have been the low-end, multi-channel surface radios built by Futaba. I believe that the 6-channel "Skysport" models that I used to buy have been discontinued, but the current most-compatible offering seems to be: http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXEFJ4**&P=SM Although it's only a 4-channel transmitter out of the box, it comes with a 7-channel receiver & I know how to "hack" the transmitter to give me those 3 "missing" channels. I don't have a defined procedure for Hitec radios, but I wouldn't be surprised if it's not only do-able but also very similar, especially since the recommended receiver for that radio is the 8-channel Supreme. Beware, though, that any such modification WILL void the radio's warranty, & isn't something that most people are willing to try to do themselves. Recommendation: Take stock of your needs as thoroughly as you can. Shop around for a radio that achieves those needs as economically as possible from a reputable maker. What you linked to may or may not be OK, but you wouldn't want to be in a situation where you need 5 or 6 channels but only have 4. JM
Probably just as well. I don't see much practical use for the thing. Then again, I've got boxes, bins, shelves, racks, drawers, etc. full of stuff that doesn't have any practical use but were fun to mess around with, anyway! JM
