I bought this TTL to RS-85 board and before connecting it to my Arduino I decided to double check (reverse-engineer) its circuit and I can see there's a 120 ohm resistor between the A and B outputs.
I know we are only supposed to terminate the end of the RS-485 bus, but this is a pretty popular board and it appears to terminate every single node of the bus if I use it.
How much of a problem can this be? Should I bother to remove the resistors? I guess it would load the signal more and more as I add more nodes, so when will this be an issue? Can this pull too much current from the MAX485 and fry it?
In case anyone is wondering, this is the resistor: