We had a great day for this years 3^rd Annual Memorial Radio Shack Sidewalk Sale. A nice and cool early morning with sun towards the end. Absolutely perfect for visiting with friends, making new friends and haggling over the price of something you need and the other person needs to sell. Old Hams and new Hams and people that want to become Hams.
This tradition started many years ago at the Radio Shack store in Derby, Kansas. The owners were both avid Amateur Radio operators and ran a small section of their store dedicated to Amateur Radio. In Amateur Radio parlance the sidewalk sale would be called a "tailgater". When Hams load up ectra gear they are no longer using and get together to sell it on the "Tail Gate" of their pickup.

This years mystery item. It goes back to at least the 1970's.

This is the face of the device.

The rear view.
I apologize for the picture. I thought I had a better view of the positioning and cables.OK. Guess it's time to tell you what it is.
WAY back in olden times when Citizen Band was all the rage this device could be used to make a sort of stealth CB antenna. Unplug the cars radio antenna lead from the back of the radio and plug it into the hole in the back. One of the cables from the box connects to the antenna connector on the radio. The other goes to the CB radio. Allowed you to use your vehicles regular radio antenna as bot the CB radio and your vehicle radio.  

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