All designs / Backgrounds / Patterns and textures
Weathered yellow painted wood planks
Patterns and textures The photo fills the whole card. Your callsign and contact details go on a light or dark panel over it, and you can choose which at the design step.

A sample station on the light panel, with the photo lightened 15 percent so the writing stays clear. The design step lets you choose the other panel or change the dimming. The bare photo is below.

Photo: "Textures IMG 1337 18" by Laurent.Jamaire, CC0 1.0, via Wikimedia (https://commons.wikimedia.org/wiki/File:Textures_IMG_1337_18.jpg). Free to use on your cards.