W
          
        
        
          ith modern Digital Command Control has come
        
        
          two very useful methods for reducing intermittent
        
        
          power feed issues with our locomotives: frog juic-
        
        
          ers and keep-alive supercapacitors.
        
        
          Back in the early days of DCC, those experimenting with the
        
        
          technology realized they could build a circuit to detect a short
        
        
          in the track and swap the polarity in the rails in mere micro-
        
        
          seconds, well before the short actually affected loco behavior.
        
        
          The result? Now reversing loops and wyes could automati-
        
        
          cally detect a polarity mis-alignment in the rails and elec-
        
        
          tronically flip the polarity to eliminate any short, with no
        
        
          mechanical Rube-Goldberg devices needed.
        
        
          Duncan McCree of TAM Valley Depot took this concept even
        
        
          further when he applied this auto-reversing approach to
        
        
          swapping turnout frog polarity. No longer did you need to
        
        
          wire separate mechanical contacts somewhere to flip frog
        
        
          polarity. You could just have a smart reversing circuit do it all
        
        
          electronically with no moving parts!
        
        
          Thanks to a frog juicer, you can now power any frog simply by
        
        
          running a single wire to that frog from the frog juicer board
        
        
          and it would take care of the rest. Instead of dead frogs you
        
        
          Publisher’s Musings - 1
        
        
          Publisher’s Musings
        
        
          by Joe Fugate
        
        
          
            Frog juicers or keep-alive?
          
        
        
          Reducing intermittent power feed
        
        
          issues with our locomotives
        
        
        
        
          MRH-Dec 2014