9x slider pot mod, pls help.

1SQ · Post by **1SQ** » Mon Sep 09, 2013 6:27 pm

http://youtu.be/UieFFNq6G6E

I found that video a while back which is an excellent tutorial on modding a 9XR (slider pot).

I bought the exact same slider pot mentioned on the video and i'm stucked in the process.

I have a 9x and the pot has 1 one wire color different from the 9XR as mentioned on the video above.

What i have is YELLOW, RED and BLACK on my pot (pot 2) and no "White" wire as mentioned on this video.

Could someone who successfully done this mod on their 9x to pls tell me which color wire from my 9x pot to connect on the slider pot solder points.

Thank you.

Post by **ShowMaster** » Mon Sep 09, 2013 6:48 pm

The pot is a voltage divider. One side of the pot will go to the +5v buss that all the other pots got to. The other side of the pot will go to ground, again just like all the other pots. The pot center wiper will go to the CPU to only one pin.
So my approach would be to use my ohm meter and measure the colored wires to another pot lead. 2 of the colored wires will go to all the other pots and those will be ground and+5v. Solder one to each side of the new slider pot. The one not gong to the other pots is the wiper wire so solder it to the slider wiper. I would think that all the other pots have the same colored wires for the ground and +5v as your wires do and the only different one would be the center wiper color that goes to the CPU pin.

All pots have one outside wire to the same ground. All post have one outside pot wire to +5v. Only the center wiper wire from each pot goes to the CPU.
So used your ohm meter to check these connections.
I would assume red to be the +5v wire, usually black is the ground wire, and the left over color is the wiper wire.
A closeup picture of the other pot wires would help with an educated guess also.
This is what you're trying to do,

Post by **ShowMaster** » Mon Sep 09, 2013 6:56 pm

Good info on pots as voltage dividers
https://learn.sparkfun.com/tutorials/vo ... plications

1SQ · Post by **1SQ** » Mon Sep 09, 2013 8:22 pm

Showmaster,

Thanks for responding. On the 9x i looked at the wires and the colors (left to right) on pot 1 are RED, YELLOW AND BLACK. On pot 2 (left to right) are YELLOW, RED and BLACK. It would be easier for me if both pots outside wires are RED and BLACK but they differ. On the new slider pot do you happen to know which is 5+, negative and signal solder points do you?

Post by **ShowMaster** » Mon Sep 09, 2013 8:55 pm

Any chance you can post a picture of the back of your slider pot?
The idea here is the slider, like the rotational 9x pot has a resistive element with a connection at each end. They both have a connection to a slider contact that when moved wipes from one end of the resistive element to the other. If ground and 5 volts are connected to the resistive end connections and you output is from the wiper to ground, the voltage will change from ground 0 volts, to +5 volts and voltages I between and the wiper is moved.
What your trying to do is wire the outside 9x pot wires, each end of the resistive 5K element to the same outside connections on your slider pot. Then the center of you 9x pot will go to the center wiper contact on the slider pot. If you do swap the two outside pot connections the pot will work backwards. Then you just swap the two outside wire and it'll work the correct way.
The only thing not to do it to solder the 9x center wiper wire to the slider end connection if you get mixed up. It then could be posable to wipe the 5v to ground and short out the 5v and pot.
To be sure about the center wiper connection post the 9x pot your trying to use again and we can find out what pin on the m64 CPU the wiper wire he's to. Once that's confirmed the other 2 will be a 50/50 chance and no harm done if backwards.
The slider pot info showing the contact labeling will help with the exact wiring tips from me or others.
The concept is very simple after you do it one time.
I have a Turnigy tx open I can check but no FlySky cases open right now.

1SQ · Post by **1SQ** » Mon Sep 09, 2013 9:24 pm

Turnigy 9x is my radio.

How do you attached a pic on this forum without giving a link? hehehhe

1SQ · Post by **1SQ** » Mon Sep 09, 2013 9:26 pm

Im trying to use wires from pot2 on my turnigy 9x (right hand side pot)
trying to find a way to upload pics right now.

Post by **MikeB** » Mon Sep 09, 2013 9:31 pm

1SQ wrote:How do you attached a pic on this forum without giving a link?

Use the full editor, then you find an "upload attachment" option at the bottom.

Mike.

1SQ · Post by **1SQ** » Mon Sep 09, 2013 10:11 pm

Top pic is left hand pot and lower pic is the right hand pot that i want to wire my slider pot.

Note the different color wires place differently on both pots.

1SQ · Post by **1SQ** » Mon Sep 09, 2013 10:25 pm

i traced the the wires from both pots across the circuit board and here's what i found.

LEFT HAND POT////RIGHT HAND POT
RED WIRE>>>>>>>>YELLOW WIRE and then goes to the 12 wires connector

The rest of the wires except for the blacks (i guess ground) run to the 12 wires connector that connects to the main board.

1SQ · Post by **1SQ** » Mon Sep 09, 2013 10:31 pm

The pot on the right hand pot is how they came from mouser.

Note the one on the left hand side has some pins removed ( 3 pins total ) as stated on the video above.

i think i have a slight idea but not 100% sure and i dont want to screw up my Turnigy 9x. Pls help.

1SQ · Post by **1SQ** » Mon Sep 09, 2013 10:47 pm

Looking at the rest of the pots in my TX the RED and BLACK wires are connected on the outside solder points on each of the rotary pots.

My pot2 (right hand) is the only one with different wire color arrangement as in YELLOW/RED/BLACK.

Did the little Chinese Lady screwed up the color code?

Clivew · Post by **Clivew** » Mon Sep 09, 2013 11:10 pm

1SQ wrote:Looking at the rest of the pots in my TX the RED and BLACK wires are connected on the outside solder points on each of the rotary pots.

My pot2 (right hand) is the only one with different wire color arrangement as in YELLOW/RED/BLACK.

Did the little Chinese Lady screwed up the color code?

Could well be!
Can you check with the pot at mid position which two wires have 5 volts across them?
If it was wired wrongly, you may have a burned out pot.
Another "cold check" would be to check continuity between left and right pots.

Clive

1SQ · Post by **1SQ** » Mon Sep 09, 2013 11:30 pm

Ever since i've used pot 2 as source for my channel 5 flight mode plus the ELEVATOR sw for switching between acro and self level on KK2.

Channel 5
Source>> POT2 (maxed to 100 all the time)
Sw>> ELEVATOR
When i turn the pot all the way to the extreme the bar graphs move up and down on the display. Does that tells me that the pot is ok?

How do i do a "cold check"?

Clivew · Post by **Clivew** » Mon Sep 09, 2013 11:52 pm

Do you have a multimeter?
If not you need to get one!

1SQ · Post by **1SQ** » Tue Sep 10, 2013 12:03 am

Yes i do. My electronic and electrical know how is limited. pls walk me thru.

Post by **ShowMaster** » Tue Sep 10, 2013 12:13 am

Ok, I had a Turnigy 9x open for repair and here's the answers.
The left pot, Red is the +5 volt connection yellow goes to the m64 and black is ground as we would expect the colors to be wired.

The right side pot ( case open on its back for these tests)
Yellow (left tab) is the +5v connection and is connected to the left pots red wire. Your ohm continuity meter should probe that.
The center tab Red wire is connected to the m64.
The right tab has a black wire on it and that's ground and also connected to the left pots right tab.
So..
On your slider pot find the wiper by putting the wiper in the center position of its travel if not marked and measuring for two leads at a time find the one the when measured from it to the other two you read about 2500 ohms (2.5K) each. This will be the wiper terminal you would solder the Red wire from the right side pot to.
The black and yellow would go to the other two slider terminals.
The big issues are making sure you know witch slider pot terminal is the wiper and witch are the two end terminals. The yellow or black wire should never be connected to the slider pots wiper terminal. This could allow you to wipe(short) the yellow and black together.
So the wire color code is worked out so now you need to identify the slider pots 2 ends of the 5k resistive element and also the wiper terminal and label them such. Then we can finalize the what wire goes to what terminal.
You're almost there.

Post by **ShowMaster** » Tue Sep 10, 2013 12:28 am

My 9x, notice the right hand pot

1SQ · Post by **1SQ** » Tue Sep 10, 2013 2:00 am

ShowMaster wrote:Ok, I had a Turnigy 9x open for repair and here's the answers.
The left pot, Red is the +5 volt connection yellow goes to the m64 and black is ground as we would expect the colors to be wired.

The right side pot ( case open on its back for these tests)
Yellow (left tab) is the +5v connection and is connected to the left pots red wire. Your ohm continuity meter should probe that.
The center tab Red wire is connected to the m64.
The right tab has a black wire on it and that's ground and also connected to the left pots right tab.
So..
On your slider pot find the wiper by putting the wiper in the center position of its travel if not marked and measuring for two leads at a time find the one the when measured from it to the other two you read about 2500 ohms (2.5K) each. This will be the wiper terminal you would solder the Red wire from the right side pot to.
The black and yellow would go to the other two slider terminals.
The big issues are making sure you know witch slider pot terminal is the wiper and witch are the two end terminals. The yellow or black wire should never be connected to the slider pots wiper terminal. This could allow you to wipe(short) the yellow and black together.
So the wire color code is worked out so now you need to identify the slider pots 2 ends of the 5k resistive element and also the wiper terminal and label them such. Then we can finalize the what wire goes to what terminal.
You're almost there.

Show master,

You confirmed my guess that on the right pot theYELLOW is POSITIVE (+), RED to the processor and BLACK is the GROUND. I was tempted 2 hours ago to just gamble and go ahead go with my guess. I applied 6 volts to the slider and measured the volts on 2 points while the slider in the middle and gave me half of 6volts which identified the wiper. Picture is marked which is which. Need to go and put together later, wifey is waiting to go to the gym. Thanks and will report back here tomorrow.

Post by **ShowMaster** » Tue Sep 10, 2013 2:48 am

Looking good, measure twice, solder once!

1SQ · Post by **1SQ** » Tue Sep 10, 2013 4:15 am

ShowMaster wrote:My 9x, notice the right hand pot
ImageUploadedByTapatalk1378772368.962406.jpg

Yup i measured again and ready for soldering tomorrow.

What is that piece to the left of your black test lead?

I see you have the Frsky DHT and looks like you have something connected to those 4 pins on the side of the DHT.

Post by **ShowMaster** » Tue Sep 10, 2013 6:02 am

This was my first attempt at adding a Frsky DHT DIY several years ago. The connector on the DHT is to connect to the RXD and TXD connections on it.
The board to the left of the test lead is a rs232 to TTL converter needed to allow the Frsky to talk to the 9x processor.
I've done many mods since this early one and use the DJT module now to have more room in the 9x case.
I've also reduced the size of the converter board.
Before

: ImageUploadedByTapatalk1378792887.128787.jpg (30.88 KiB) Viewed 16257 times

After

1SQ · Post by **1SQ** » Wed Sep 11, 2013 12:18 am

Slider installed and wired. Powered on and thank you no smoke. Now i can do inflight tuning of my KK2 and CC3D without taking my hand/fingers off the sticks.

1SQ · Post by **1SQ** » Wed Sep 11, 2013 12:28 am

Thanks to all who help me accomplish this task and specially to Showmaster.

Showmaster

What do you mean by "rs232 to TTL converter needed to allow the Frsky to talk to the 9x processor".
Is that telemetry or flashing the 9x with firmwares like er9x and C9X?

Post by **ShowMaster** » Wed Sep 11, 2013 1:33 am

I see you're using the DJT DIY. To make more internal case room unsolder and remove the metal V strap. It's left over as part of the fm antenna grounding system (counterpoise) and only gets in the way with the 2.4 upgrade.
The RS232 to TTL converter is usually required as part of the Frsky to 9x telemetry mod. There is another way to do it but not usually with the DHT and it requires more critical soldering. ( I posted this for those that may challenge it).
The Frsky TXD RXD built in interface is a RS232 based logic protocol. The idea is a 0 logic is a + 3-5v and a 1 is a -3-5v. The 9x being TTL requires a +3-5v as a logic 1 and ground as a logic 0 or close to it.
To allow the Frsky DHT or DJT to talk to the 9x m64 processor it must see a ground to +5 volt transition for 0 and 1.
If your not using a SP add on board you would do the soldering mods required to display the telemetry on the 9x board and usually use the level changer board in my picture.

I see you do have a cable connected to your DHT data port. Do you have working telemetry displayed on your 9x LCD now?

Good work on the slider pot, now you can help others out with it.
SM

Post by **ShowMaster** » Wed Sep 11, 2013 1:46 am

I also see the plastic raised part around your module bay pins. Next time you have the board out cut that raised part off. It's only purpose is to stop non Turnigy modules from being plugged it. It again offers no operational contribution so you'll gain more JR pinout module options. One is plugging in a Frsky DJT and then you can have 16 channel operation.
SM

1SQ · Post by **1SQ** » Wed Sep 11, 2013 1:57 am

, I think you just me dumber with your explanation on R232 and TTL. I was in the Navy but as a mechanic and my electrical and electronic understanding is limited.

I have telemetry but its only the RSSI that is readily available. On my RX (D8R-XP) i installed the jumper on A1 and X so that it will give me flight battery voltage. I was told that the voltage display is useless because it wont display the voltage as it degrade in volts. I want to maximize this telemetry mod with what i have. I plan on buying a sensor hub plus sensors but not anytime soon because i still fly LOS. So far my 9X has the C9X loaded, frysky DHT , screen light and just moved two switches in the back as my "OH s*** SWITCH OVER NOW, NOW!

I replaced my 3 way flight mode switch to something similar but it has 6 poles (3 on each side). I'm wondering if its possible to add LED for visual feedback since this 3 way switch is now located in the back with the slider.

Post by **ShowMaster** » Wed Sep 11, 2013 2:39 am

All posable but it requires more tidy soldering.
So I'm still confused,
Do you have a display of RSSI?
What's the black cable doing that's coming out of the DHT side data connector?
I assume you have a display because of the comments?
As for the voltage the telemetry feeds back to the Frsky DHT, it's pretty accurate .
I'm confused you've heard it isn't?
More info on your setup please.

1SQ · Post by **1SQ** » Wed Sep 11, 2013 8:06 am

http://openrcforums.com/forum/viewtopic ... 841#p58841

Here is link to my post regarding telemetry.
i can see voltage display on the radio but i dont know how to set it.

1SQ · Post by **1SQ** » Wed Sep 11, 2013 8:10 am

http://www.rchacker.com/projects/turnig ... -telemetry

This is exactly what i followed for installing the wires on the side of the DHT.

openrcforums