timdoug's tidbits
2024-01-15
Fixing S/PDIF output levels
The Monoprice S/PDIF TOSLINK to RCA coax adapter is a handy device, but its output is pretty hot -- my oscilliscope reads a bit more than 1V pp into 75Ω termination, about twice what the specification describes.
After the 100nF cap on the 74HC04's output was a 150Ω resistor; I replaced it with a 390Ω one, now it's within spec at ~480mV pp. (I also lifted a pad, can't see the bodge on the other side though!)
