Did you get my PM?

Hello again everyone, i made encoder and decoder both with ic 4017, the ppm output from the decoder is fine and can be altered by pot position. But the decoder doesnt give the right output, sometimes the on pulse period from the decoder output equal to pot position but somtimes it give longer or shorter duration. How can i fix this? note that in the picture i attach the voltage is somehow inverted

in the first picture the red line shows clock input for ic 4017 in the decoder and the green line is output from channel 2, note that the third output from left has less period than it supposed to

in the second picture the red line shows reset input for ic in the decoder and the green is output from channel 2,  note that the 2 output in the right has less period than the other