[ARC5] Mystery Remote Control for R-23/BC-453?

[D C _Mac_ Macdonald]

What's this?  Late model aircraft controller for the "old" LF nav receivers? 
 
http://www.ebay.com/itm/221417920128
 
 
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* 73 - Mac, K2GKK/5 * 
* (Since 30 Nov 53) * 
* k2gkk hotmail com * 
* Oklahoma City, OK * 
* USAF & FAA (Ret.) * 
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