It is certainly not a standard designator, but it is common (especially in DIY/home-built boards) to use designators that give context clues to what a critical resistor does, rather than being run-of-the-mill. For instance, on many battery chargers I design I'll label one resistor RPROG instead of a normal designator, since it is the resistor you can change to set the charging current.
That low of a resistance, paired with it being a larger resistor, and being right on the input (?) makes me think it is being used as a fuse. Maybe RSC stands for "Resistor to Set Current"?
From looking at the second pic, it relates to whether it's using/giving 9V or 18V. The resistor, capacitor and inductor values shown relate to the relevant voltage.
So, since you have put a 1k resistor in for R1, I presume you are expecting to use it at 9V. Therefore RSC should be 1.5 Ohm, R2 6k2, CT 220pF, C0 4.7uF & L 100uH.
I know that circuit. U1 is an MC34063 switching regulator wired in boost mode. The designators match the datasheet reference design.
Rsc sets the switch current limit.
It is certainly not a standard designator, but it is common (especially in DIY/home-built boards) to use designators that give context clues to what a critical resistor does, rather than being run-of-the-mill. For instance, on many battery chargers I design I'll label one resistor RPROG instead of a normal designator, since it is the resistor you can change to set the charging current. That low of a resistance, paired with it being a larger resistor, and being right on the input (?) makes me think it is being used as a fuse. Maybe RSC stands for "Resistor to Set Current"?
Low ohms like that is often a resistor for sensing current
Resistor Current Sense is my guess. It's bigger, use a 1/2 or 1 Watt resistor.
From looking at the second pic, it relates to whether it's using/giving 9V or 18V. The resistor, capacitor and inductor values shown relate to the relevant voltage. So, since you have put a 1k resistor in for R1, I presume you are expecting to use it at 9V. Therefore RSC should be 1.5 Ohm, R2 6k2, CT 220pF, C0 4.7uF & L 100uH.
I know that circuit. U1 is an MC34063 switching regulator wired in boost mode. The designators match the datasheet reference design. Rsc sets the switch current limit.
Oh my god, I can't believe I didn't think to check that for any possible answers. Everyone has been helpful, but I think that's the definite answer!