I just bought a used T-Series with the SM58 handheld. Aside from needing to order a new power cord (worn at wall-wart end), I need to know if it's okay for both the receiver A AND B lights to be lit at the same time. The operating guide mentions one or the other. I've "home" tested the system and it works very well.
Yes, it is just fine if the A and B lights are both lit.