Axelrod says 66 ft for STP, 106 for ribbon cable, and 133 for UTP. These are based on typical cable capacitances, receiver input capacitance of 100 pF, and a baud of 20 kbps or less.
These are calculated, based on TIA-232 recs.
I don't know if 100 pF is usual or not, for an 'input capacitance'.
TB A+ Partner Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense. -Buddha
