need help on reading futaba 3KP ppm signal

[chinweihung]

Dear All,
I'm trying to ready out ppm signal from my 3pk with oscilloscope. I can ready clear signal form the DSC port, but can't read from the pin connector(which connect to module).

I did my search, the pin one from left is the PPM pin and the pin 4 form left is the ground. It should be correct to measure on these 2 pins.

what did I do wrong?

[iter]

Futaba radios only transmit if they detect an RF module. You may find this thread useful: http://www.rcgroups.com/forums/showthread.php?t=387442

Ari.

[chinweihung]

thanks, I will try to ground pin 3 and try again.

[TheSteve]

The 3PK will output PPM data with or without a module. To see any data though you'll need a pullup resistor on the PPM output when you don't have a module installed.

[chinweihung]

Great thanks Steve, one more question, what voltage level should I pull up? to 5V or to the battery voltage pin? what resistor value you would recommand?

[TheSteve]

You can go as high as the battery voltage but I'd recommend 5 volts with a 10K resistor.