polarity of DC 12v connector on EXP GDC 8.5c
It's center positive. If using these 5.5x2.5mm barrel plug with a screw terminal then yellow goes to the + terminal and black to the -.
thanks a lot, i just need wait the transformer arrives, its as this https://mlstaticquic-a.akamaihd.net/fuente-12v-8a-para-camaras-mfshop-D_NQ_NP_638872-MLU26774336195_022018-F.webp
12v 8a - 5.5 x 2.1 mm national conector