Mariss, would a Schmitt-trigger with a low threshold correct any slow ramp up time on the opto LED? Sorry I haven't read the HCPL-2531 datasheet yet. Not sure if anyone makes a highspeed opto with a configurable Schmitt-trigger output. Then again there's always common mode noise that might obviate a low volt input trigger.

Agreed on the CNC4PC boards. I'm not a user (yet) but they look solid.

Yes, both contacts around 16:00 GMT and atypical conditions - especially on 10m.

Mandatory Spanish post - repeat after me: "El burrito is to go, por favor."

JR