need help with "Digital Switching"

hey people new here i found a switching system schematic online but my prob is that it has 16 outputs and i only need 4 can sum one help me on this heres the link to the thingy **broken link removed**
thanks

anyone know

81j10honcho said:

hey people new here i found a switching system schematic online but my prob is that it has 16 outputs and i only need 4 can sum one help me on this heres the link to the thingy

Click to expand...

Swap out the 74LS154s with one 74LS139, a dual 2 to 4 line decoder. Your binary up/down counter will then have some unused states (counts 4-15). Also, the input switches (up/down/reset) don't look very well debounced...