[Espeefan]

Not sure I understand your question 100%.

If you want to trigger a relay 'on', from a radio receiver channel, to run a string of LEDs in series, with the correct resistor, then yes, you can do that. The relay allows you to activate the lights, with a low voltage, low current control signal, and to power a load with a separate, higher voltage, or higher current source. If that makes sense, and answers your question?