https://www.dropbox.com/s/u2ah8y2gcel2rc0/mod60.ms10?dl=0

its a mod 60 counter with a start and reset using 74ls93n ic chips.

 

Hi. I'd like to help you out but the image is so poor that I can't tell how the counter is connected.
In general terms the counter is reset to '00' by the start signal.
Whenever the Least Significant Digit (LSD) is a '9' AND the Most Significant Digit (MSD) is NOT '5'; the MSD is incremented by '1' and the LSD is reset to '0'
Whenever the LSD is a '9' AND the MSD is a '9'; both digits are reset to '0'

That's it in a nutshell unless there are small details hidden by the unreadable schematic.

 

i'll post a clearer picture. thanks for the explanation so far.

 

Hi. I'd like to help you out but the image is so poor that I can't tell how the counter is connected.
In general terms the counter is reset to '00' by the start signal.
Whenever the Least Significant Digit (LSD) is a '9' AND the Most Significant Digit (MSD) is NOT '5'; the MSD is incremented by '1' and the LSD is reset to '0'
Whenever the LSD is a '9' AND the MSD is a '9'; both digits are reset to '0'

That's it in a nutshell unless there are small details hidden by the unreadable schematic.

heres a clearer pic above

 

That's better but I still can't follow the critical nets from the counter outputs to U6{A,B,C,D} inputs

 

That's better but I still can't follow the critical nets from the counter outputs to U6{A,B,C,D} inputs

click on the dropbox link and you'll find the original file there