PWM signals to analogue port

Hello, I connected the output of an analogue joystick to the analogue input port of Arduino UNO3. The joystick was powered from the 5V port of the Arduino and I connected the ground of the two together. It worked fine. I could get values between 0 and 1023 with about 600 as the neutral value.

Now, I try to do the same thing but import analogue signals from the joystick to the analogue input port of a remote controller (via direct wire connection), transfer the signal to the receiver via remote control and then import the values to the analogue port of Arduino.

I only saw values of about 600 on the computer screen. When I moved the joystick down, the values became 0. When I moved the joystick up or allowed it to rest in neutral position, the values were about 600.

How come? Anybody knows how to fix this problem?

Note that the receiver receives analogue values from the analogue port of the sender but outputs PWM rather than analogue values on the receiver side. Also, the receiver and sender circuit accepts at most 3.3 V. The sender and receiver each is powered by a 3V battery box. The Arduino draws power from the USB port of my MacBook Pro.

Is the problem due to sending PWM from the receiver to the analogue input port of the Arduino?

Add a RC low pass filter to each PWM line, to get a somewhat stable DC voltage from the PWM signal.

You may be better off with the Servo library, where every analog (joystick) value translates into pulses of 1-2 ms, which can be measured using digital pins and timer functions (pulseIn), provided that the 3V levels are sufficient to trigger the digital input pins.

petercohen: Now, I try to do the same thing but import analogue signals from the joystick to the analogue input port of a remote controller (via direct wire connection), transfer the signal to the receiver via remote control and then import the values to the analogue port of Arduino.

I have no idea what this means. Perhaps you can draw a diagram and post a photo of it? Also, post a link to the datasheet for the remote controller.

What do you mean by the "receiver" ? Please post a link to the datsheet if appropriate.

What do you mean by "via remote control" ?

I would expect that the signals from the "remote control" would be digital rather than analog/

...R

DrDiettrich:
Add a RC low pass filter to each PWM line, to get a somewhat stable DC voltage from the PWM signal.

You may be better off with the Servo library, where every analog (joystick) value translates into pulses of 1-2 ms, which can be measured using digital pins and timer functions (pulseIn), provided that the 3V levels are sufficient to trigger the digital input pins.

Thanks. What are the recommended value for the R and C?

Is there a tutorial on how to use the Servo library to translate the analog joystick value into pulses to be measured using digital pins and timer functions?

Without access to an oscilloscope to test the output of the receiver, I tried a few resistors and capacitors that are available. The best combination is: 10K, 1e-6F. When the joystick was in neutral position, the output values were around 640. When I moved the joystick down slowly, the output decreased from around 640 to zero. This looks good. However, moving the joystick up did not change the output which stayed at around 640. Any suggestion on how to resolve this issue? Thanks.

Please post your circuit diagram. All your informations are quite fragmentary.

Enclosed is the circuit diagram. Could you please have a look? Thanks in advance.

@petercohen, You still have not posted links to the datasheets for your transmitter and, more especially, the receiver.

You have not even identified the names of the parts.

...R