Don't have any pix, but our board has slots covered with clear lexan and a 3/8 dowel across each row of slots, with clothes pins clipped to them. Each slot has a number on it for the specific frequency, and the clothespins have a small placard with the same number. The idea is to leave your AMA card in the slot and take the correspondind clothespin and clip it to your Tx antenna. Anyone coming to the board will see a card in the slot and no pin for the frequencies in use. Lets you know who is using what, so you can ask to share if "your" freq. is in use. We encourage,at our club, to return the pin after each flight in case someone else wants to fly in between the other user's flight. We added doors with corkboard on the inside to post notices on, and you can lock up the whole thing when done. It's about 2 x 4 feet, mounted to a pole at the field