I have a RCB7x radio , all of a sudden the throttle potentiometer broke off. Now i have replaced the throttle and it works.
But the problem is that , when verified in the stick movement display - the movement is not as much as in real world.
I have also tried adjusting the EPA to +-150% still the movement is very little.Is there any way to calibrate the stick movement in the software?
Could anyone specify the manufacturer or the original model of this OEM branded radio ?
may the potentiometer that you replaced was different in Ohms from original, try to replace with new potentiometer having the same Ohms value as original,
To get the value you can measure Ohms from broken or other working potentiometer in that tx.
You're right , the original POT was 5K but this new replacement is 5.2K , still the output will be the same voltage at the same wiper position ?
0.2 ohms will be a major diffrence in this case.but u can use less than 5k ohms potentiometer with trim enabled.
But these replacement pot are not easily available - the shape is very specific
Dont try if U hav enough experiance and dont blame me if it goes wrong,
if u hav any doubt just ask me before doing this.
i done this many times and the result is success
Try dismantling POT and solder some led in the joints between resistive meterial and the connector as shown in the picture will reduce resistance,
That's an excellent idea , but this is a sealed plastic case pot -so it's difficult to make this mod
can u post images of the pot?
Image of the shaft/wiper of the POT and the original broken pot from RCB7x
For Decreasing resistance of a pot there is no need to open and add lead to the resistance track, just add an appropriate value of resistance in parallel to POT !!!
You have 5.2K POT and need to decrease it to 5K, Just add a 130K Resistor in parallel to POT.
In parallel combination, Total resistance R=(R1R2)/(R1+R2)
Assume your POT is R1 = 5200ohm,
and total resistance needed is 5000ohm,
So, 5000=(5200*R2)/(5200+R20,
By deducing R2=130000ohm = 130K.
:thumbsup: :thumbsup:
+1 to sooraj.
Thanks, Sir.
I am new to rc, however know some thing in electronics and embedded systems. :hatsoff:
Found the problem when I opened up the POT. In normal POT the resistive trace is available for 210 deg or so ,then the whole range of voltage variation is available only in 210 deg. But in this case of gimbal POT the total variation of the voltage must be constrained within the movement of the gimbal so the trace is available only for 80 deg which makes it difficult to replace it with a normal POT.
Removed the case of the POT.
Transplant the good wiper knob to the damaged POT
Fix the wiper contact onto the new knob
The resistance track constrained within 80 deg.
Good {:)} {:)} {:)}
Check and post the results.
Normal POT trace nearly 300 deg
(http://www.geofex.com/article_folders/potsecrets/pot5.JPG)
There was misalignment in fixing the case
The range works as expected
In general , its very rare to find a replacement POT for the gimbals in our Radio systems. You have to buy a new gimbal replacement unit instead of a single POT costing around Rs.10 .