Re: Final assembly...
Posted: February 20th, 2021, 1:01 pm
I had a go at this this morning.
I reduced R42 from 4K7 to 3K9 and reduced the effective resistance driving the clock phases from 235 ohms to 167 ohms. Here is the result.
td1 55 ns
td2 120 ns
td3 135 ns
tr 13 ns
tf 7ns
Pulse widths in picture below.
Behavior is the same though. if the 2SIOJP is the last card on the MB, it receives spurious characters. If it's between 2 cards it's fine.
I reduced R42 from 4K7 to 3K9 and reduced the effective resistance driving the clock phases from 235 ohms to 167 ohms. Here is the result.
td1 55 ns
td2 120 ns
td3 135 ns
tr 13 ns
tf 7ns
Pulse widths in picture below.
Behavior is the same though. if the 2SIOJP is the last card on the MB, it receives spurious characters. If it's between 2 cards it's fine.