I know that open collector outputs are effectively either 0 V or high-Z.
I also know that TTL chips tend to read a disconnected output as high, but that really you should have something like a 1 kΩ pull-up resistor for safety.
But does the warning about a pull-up resistor still apply if you're linking an open-collector output to an input?
As a concrete example, I want to implement OR logic with an open-collector NOR chip (74LS33) by connecting pins 12, 11, and 10: pins 8 and 9 are the inputs and pin 13 should be the (open collector) OR of 8 and 9.
Do I need to have a pull up resistor attached to the pin 12-11-10 net? Or will the open collector output for pin 10 still reliably drive the logic value for 11 and 12 high?