McDonalds (San Carlos, CA)
From The RadioReference Wiki
The McDonald's drive-thru at the San Carlos location broadcasts on frequency 457.5375MHz and uses a CTCSS tone of 71.9Hz.
The channel is closed until someone drives up to the order board. A tone is emitted to alert the order taker a vehicle has arrived to place an order then the channel opens up and you are able to hear both sides of the conversation.
Location
The San Carlos McDonalds is located at 180 El Camino Real San Carlos, CA