K1803 Input voltage

Hello,
Previously when I used this kit, it was to strong for its application.
I heard it was probably the input signal being to strong.
My question: when I chanche the value of R1 to a lower value to allow more bleed to ground, will this work? or am I thinking completely wrong? :crazy_face:
thanks in advance!
link to manual with schematic: https://www.velleman.eu/downloads/0/illustrated/illustrated_assembly_manual_k1803_rev2.pdf