Radio Potentiometer Wiring

[SMR 510RR]

So I have search high and low for this information but I cant seem to find much about it on here or anywhere for that matter.

Here is what I need to know:

How do the 3 connections to the pot get interpreted by the board?

How do I determine what connection is what on the board?

Any other info that pertains to this subject would be helpful.

Thanks,
SMR 510RR

[SMR 510RR]

Or a link to some information on the subject would also be helpful.

[losikid]

The outer wire are 5v and 0v. The middle one is a signal wire, as the pot turns it allows different voltage to go into the signal wire. the signal wire then goes to the encoder and encodes it into ppm/pcm, then off to your rx. what are you trying to do?

[SMR 510RR]

Im trying to do a bit of analog mixing to try out some concepts. It looks like it is going to be harder than I had thought to do what I wanted. I may just wait for the experts to get their setups up and running or wait for the 4pl to come out.

[losikid]

What radio are you trying to do analog mixing with.

[SMR 510RR]

Originally Posted by losikid

What radio are you trying to do analog mixing with.

I was thinking of picking up a used TQ3 or something to mess with.

[losikid]

Only way to do this is to find a dual ganged pot with the same rotational properties as the original (235* i believe) and this will allow you to have mix, 1 ch only or a crab type setup. I think anyways i have never tried it this way but it seems dual ganged pot will eliminate the problem with analog mixing. In a perfect world you should be able to connect the signal wires together and have a mix but you have different resistances and such running through the wires always offsetting the ch a few percents. And you can't trim one ch and not the other in a hard wired mix because both chs are tied together. Only exception is that i'm not sure how the trim pots on the tq work. This may allow you to trim 1 ch equal to the other. Also dependent on the application it wouldn't matter if the ch pos are perfectly the same because you can always program esc's that way or adjust linkage/move servo horn on a servo. But when you get into like crab steer and proportional mixing it doesn't work out too well. What application were you planning to mix the two chs?

[RIG_RIDER]

If you have some time on your hands, take a stroll though this thread.
My Modded TQ3 Update - Added EPA pots

[SMR 510RR]

Originally Posted by losikid

Only way to do this is to find a dual ganged pot with the same rotational properties as the original (235* i believe) and this will allow you to have mix, 1 ch only or a crab type setup. I think anyways i have never tried it this way but it seems dual ganged pot will eliminate the problem with analog mixing. In a perfect world you should be able to connect the signal wires together and have a mix but you have different resistances and such running through the wires always offsetting the ch a few percents. And you can't trim one ch and not the other in a hard wired mix because both chs are tied together. Only exception is that i'm not sure how the trim pots on the tq work. This may allow you to trim 1 ch equal to the other. Also dependent on the application it wouldn't matter if the ch pos are perfectly the same because you can always program esc's that way or adjust linkage/move servo horn on a servo. But when you get into like crab steer and proportional mixing it doesn't work out too well. What application were you planning to mix the two chs?

I was/am trying to do proportional dual esc mixing. I found some dual ganged pots that are reversed from side to side called "Blend pots " used in guitars to blend the input from two pickups to alter the tone.

These blend pots have a center detent, supposedly at the center there is 100% of both "channels" passed through and as you move away from center one "channel" or the other will be proportionally taken out of the mix. (Remember this is what I have read on some guitar forums so I was going to apply the same theory but in reverse)

I was thinking that I could run one pot into both sides of this blend pot to control the balance of two channels but it looking like it would be harder than I was thinking it would be.

Maybe I am missing something but it looks like it would be much harder that I had originally thought it would be. I have a couple different pots on the way to mess with, I have a couple junk radios to play around with so I am going to connect some pots up and see what happens.

Originally Posted by RIG_RIDER

If you have some time on your hands, take a stroll though this thread.
My Modded TQ3 Update - Added EPA pots

I have looked through it multiple times but couldnt find much if any information about mixing the channels. It seems like anyone who wanted proportional control of the rear steering ended up with a pot rather than a switch and all that would do for me is let me have two triggers. I still want one trigger but also want the ability to proportionally adjust the mix between front and rear.

Let me know if I missed something in there but I read through it a couple times.

[losikid]

How does the guitar pot work actually like what is it doing to the input voltages, ideally it can work from what you said but i'm not sure if you are describing it right. Next i have tried and failed many times at being able to proportionally control a slave ch from its master ch and i can't figure it out. Only way i can figure out is to implant it into the firmware which i'm working on building a custom radio which will allow this. And how i have my radio set up now. to add a preset percentage (on the cpu) as your max then being able to move that far away from your master chs current position, giving a semi proportional control. Your cheapest solution would to buy a 3e and have wantasummit hack it for you (its a firmware hack i believe) or build/buy a stick conversion radio like mine. IMO i have never used a 4pk but what i have set up or what want a summit is doing is better than what the 4pk can do. Because you have one switch on the 4pk that will allow you to turn on and off a "dual rate" to your mixing. But what you want is variable rate selected by a pot which is what wantasummit has done or i have a variation of it in my radio which is actually a better design in my head because it will allow me to actively and easily change the rate while driving and it also allows for full independent control of both escs when the mix is turned off. OH and when at a dead stop it will allow me to load up my rear end or unload it without actually moving my wheels because there is such a low percentage you can really do a slow 1% unload and never have your gear train move just unload the stress on it.

[SMR 510RR]

Originally Posted by losikid

How does the guitar pot work actually like what is it doing to the input voltages, ideally it can work from what you said but i'm not sure if you are describing it right. Next i have tried and failed many times at being able to proportionally control a slave ch from its master ch and i can't figure it out. Only way i can figure out is to implant it into the firmware which i'm working on building a custom radio which will allow this. And how i have my radio set up now. to add a preset percentage (on the cpu) as your max then being able to move that far away from your master chs current position, giving a semi proportional control. Your cheapest solution would to buy a 3e and have wantasummit hack it for you (its a firmware hack i believe) or build/buy a stick conversion radio like mine. IMO i have never used a 4pk but what i have set up or what want a summit is doing is better than what the 4pk can do. Because you have one switch on the 4pk that will allow you to turn on and off a "dual rate" to your mixing. But what you want is variable rate selected by a pot which is what wantasummit has done or i have a variation of it in my radio which is actually a better design in my head because it will allow me to actively and easily change the rate while driving and it also allows for full independent control of both escs when the mix is turned off. OH and when at a dead stop it will allow me to load up my rear end or unload it without actually moving my wheels because there is such a low percentage you can really do a slow 1% unload and never have your gear train move just unload the stress on it.

I have been watching your thread as well as wantasummit's and like what I am seeing. I am trying to cheaply try out proportional mixing to see exactly how I would want it setup before investing a whole lot of money into it. And if I came up with something that worked well enough I may just stick with it.

I am not exactly sure how the guitar blend pots work so I ordered a couple to test out, I will post up exactly what they are when I get them.

I am almost possitive that the 4pk(s) and 4pl are much more capable than you are thinking they are. Watch this video from the 4pk setup thread http://www.youtube.com/watch?v=b5cYbFT45xg

[rmdesignworks]

Originally Posted by losikid

The outer wire are 5v and 0v. The middle one is a signal wire, as the pot turns it allows different voltage to go into the signal wire. the signal wire then goes to the encoder and encodes it into ppm/pcm, then off to your rx. what are you trying to do?

If Im not mistaken a Pot is 0k ohms to 5k ohms,,,,not volts bro. A potentiemeter is a variable resistor...turning it varies the resistance across the blade and strip from one contact to the other.

[losikid]

yea thats a single 2 pos switch that turns a dual rate on and off, or a mix rate maybe, does the same thing. So he goes from 100% master 100% slave to 100% master 70% slave or something like that. As too where with wantasummits hack you can change what percentage you want the slave ch to be by simply turning a pot and on mine you have a more active control that max % are selected on cpu then you have + or - that percentage of full throw variation from where ever your current master position is. So if your master is at 50% forward and you want your slave to be 35% forward you would move the lever down (or up if you reverse the lever) 15% and it will move the slave 15% less than the master. If your at a dead stop you basically have +/-your percentage for rear dig only. or turn mix off and you have full independent control. No other pistol grip radio has full independent control of both esc's other than mine. Heres a vid of mine, you may have already seen it. http://www.youtube.com/watch?v=ZjEO4eMVeRs i've done a few mods since then to accommodate the 4ws but i think the mods were better overall.

[rmdesignworks]

Dual 5K pot here....

http://parts.digikey.sg/1/1/206003-p...ku5021s28.html

[losikid]

Originally Posted by rmdesignworks

If Im not mistaken a Pot is 0k ohms to 5k ohms,,,,not volts bro. A potentiemeter is a variable resistor...turning it varies the resistance across the blade and strip from one contact to the other.

So tell me, why do you put resistors on between a LED and a battery? Because a resistance in a line decreases a voltage to the required voltage needed for the led. Well and it works as a fuse as well. Pots are also know as voltage dividers. Guess why.

I promise you man i know what a pot does i have built 4 custom radios that originally all 6 chs were pots. And i have been experimenting with radios for the last few months.

[losikid]

Originally Posted by rmdesignworks

Dual 5K pot here....

http://parts.digikey.sg/1/1/206003-p...ku5021s28.html

They make smaller ones, those are way to big for the trigger part and almost or is two big for the steering.

[SMR 510RR]

Originally Posted by losikid

yea thats a single 2 pos switch that turns a dual rate on and off, or a mix rate maybe, does the same thing. So he goes from 100% master 100% slave to 100% master 70% slave or something like that. As too where with wantasummits hack you can change what percentage you want the slave ch to be by simply turning a pot and on mine you have a more active control that max % are selected on cpu then you have + or - that percentage of full throw variation from where ever your current master position is. So if your master is at 50% forward and you want your slave to be 35% forward you would move the lever down (or up if you reverse the lever) 15% and it will move the slave 15% less than the master. If your at a dead stop you basically have +/-your percentage for rear dig only. or turn mix off and you have full independent control. No other pistol grip radio has full independent control of both esc's other than mine. Heres a vid of mine, you may have already seen it. http://www.youtube.com/watch?v=ZjEO4eMVeRs i've done a few mods since then to accommodate the 4ws but i think the mods were better overall.

Yea well in the video he has it setup with 10% steps...Im not sure what all the options are but each click of one of the switches equates to a 10% drop in power to the rear esc. This is good because you can not go into the negative (that I am aware of) so you will never have your rear go in reverse. Also no matter how much/little input you give it it stays linear from front to rear. That is what I am looking for but if it was controlled by a lever so you could mix on the fly that would be the best in my opinion. The hard part is maintaining linear response as well as locking out reverse, at full lever you should be in front dig in the other direction it should be rear dig. Between the two max stick inputs you should be at a %age between 100 and 0.


Well a little update from me...I got it "working". I just used the two pots that were in the radio I am messing with (losi AM radio from a Micro T). I wired up the steering pot like usual but ran a wire from the "Signal output" wire to the "voltage input" or "Hot Input" on the second pot. Then I just connected the ground wire and signal wire to the second pot as usual. Its not "working" perfectly but it is a start. With the second pot at its lowest resistance both servos (I am testing with servos because it is easier) follow one another decently well (a little bit off but this is the first attempt, im guessing that this is due to the added resistance of the slave circuit). If I give the second pot some input it quiets down the "slave" servos movement, that is exactly what I am looking for.

Of course it is not perfectly linear and I bet if I tried out enough pots I could get better results but I think that I am on the right track here. I think I will get some smaller K pots to try out. The second servo stops with about 1/8th travel so I know I can go down and will also gain some resolution. I may also try some different taper pots to see if that helps, I am thinking that an audio taper may help make the mixing smoother.

I am open to suggestions, as always I am in way over my head but I am getting somewhere.

[SMR 510RR]

One more question, sorry for all the double posting but I am trying to make this thread a little easier to read.

Does anyone have a way to analog dig? I am think that if I could find a 2 position switch that was double gang ON (ON) with two different circuits I could use the momentary circuit at middle voltage to leave the esc in neutral. I wish I could explain it better but I think that kinda makes sense.

Originally Posted by losikid

The outer wire are 5v and 0v. The middle one is a signal wire, as the pot turns it allows different voltage to go into the signal wire. the signal wire then goes to the encoder and encodes it into ppm/pcm, then off to your rx. what are you trying to do?

Originally Posted by rmdesignworks

If Im not mistaken a Pot is 0k ohms to 5k ohms,,,,not volts bro. A potentiemeter is a variable resistor...turning it varies the resistance across the blade and strip from one contact to the other.

You are both right as far as the info I have gathered.

Losikid was referring to what the wires are that go to the pot not what the pot does.

Rmd is referring to what the pot does.

Both of you are correct, no need to fight...

[rmdesignworks]

Originally Posted by losikid

So tell me, why do you put resistors on between a LED and a battery? Because a resistance in a line decreases a voltage to the required voltage needed for the led. Well and it works as a fuse as well. Pots are also know as voltage dividers. Guess why.

I promise you man i know what a pot does i have built 4 custom radios that originally all 6 chs were pots. And i have been experimenting with radios for the last few months.

hey man I didnt come after you but if someone asks for a 5vdc pot they are gonna run into trouble,,if they ask for a 5k pot they wont. A pot is not listed as 0vdc - 5vdc,,they are listed as 0k-5k. I too know what they do,,and I never said anything about what you know,,and I really dont appreciate the sarcastic manner in which you replied. If people are gonna give information then give it the same way other's are gonna ask or parts.

I have also designed some radio gear including a 72 channel multiplexed radio...just no market for it....I apologize for intruding on the discussion.

[losikid]

Originally Posted by rmdesignworks

hey man I didnt come after you but if someone asks for a 5vdc pot they are gonna run into trouble,,if they ask for a 5k pot they wont. A pot is not listed as 0vdc - 5vdc,,they are listed as 0k-5k. I too know what they do,,and I never said anything about what you know,,and I really dont appreciate the sarcastic manner in which you replied. If people are gonna give information then give it the same way other's are gonna ask or parts.

I have also designed some radio gear including a 72 channel multiplexed radio...just no market for it....I apologize for intruding on the discussion.

I was just answering the question, "what do the wires do" as i interpreted what was asked. If he asked what size pot is it i'd be happy to say a 5k 235* pot which it seems i did say somewhere in here but i don't remember.

Smr. Not sure if you can tell, but when you have them mixed you have different center points on the ch's. Which doesn't really matter when your not disconnecting and connecting ch's. But yes you can do a simple disconnect switch, spdt (on-on) and have a front dig only. Do this inbetween your steering pot and vr pot or on the signal coming out of the vr pot, it doesn't really matter. But you may come across a problem. When you mix and unmix your chs will have different center points and it may or may not be noticeable. Since i don't have a tq3 in front of me i can't quite say if there is a way to trim it out. Only way i think you can is to check and see if the trim pots on the tq currently will trim each ch individually without affecting the other. Do this by when they are mixed together move the throttle trim and see what it does then move the 3rd ch trim (on the board, pokes out through screw hole normally) If they move only the ch they are supposed to and not the other then were in business if they do affect each other then i'm not sure how to do it without dual gang pots. and thats gonna be ultra tight on the throttle pot you will have to drill through the case and possibly more like i had to on my radio.

Oh ok so it moves 10% either way each click.