I'll be the first to admit my lack of knowledge. I was just trying to explain to the OP in more detail as best I understood it. I appreciate your knowledge and advice (I'm learning a lot here too) and, as I stated before, the OP should default to you.Post 32 was supposed to allay your fears. Elec_mech had raised the issue of damage. He doesn't understand TTL very well. I started designing digital logic circuits before the first TTL IC family (SUHL, Sylvania Universal High-level Logic) was introduced in 1963. I'm not tooting my horn, I'm just trying to establish my credibility.
So going beyond the rated current limit does not guarantee damage, just that the output logic may not "appear" correct to other digital inputs and heat dissipation could be an issue? Is it therefore safe to do this within certain instances?
So what are the current limits if a TTL output is strictly used to power something like an LED and not connected to another input? At least to point where one needs to worry about damage either by overcurrent through the pins or heat dissipation throughout the IC?
derderppolo, as Ron stated, if you could post a schmatic of the circuit you are using, we (or at least Ron) can shed light on why the LEDs are dim when they are supposed to be off.
I still suggest following the schematic Ron posted in #24. That should solve your problem.