This is the motor driven tank coil for a Collins ATU. It is a vintage piece that has not been used. I believe it to be a sub-assembly to the Collins ATU\'s 506-1199-004 & 522-0092-004. There may be more applications I am unaware of.

I think these tuners were used primarily in aircraft. If you have one of these and need some parts, this one is for you. Still attached is the sticker from Collins showing it passed inspection. Also enclosed is a handwritten sheet showing the hook-up for this unit. I don\'t know who drew it up, but all the interfacing wiring is shown.

As the geardriven motor turns, the stainless steel strap winds from the tank back to the drum, changing inductance to the antenna. This is a nice piece in beautiful shape.

Thanks for looking.