Alternatively L1 and D2 may be functionally viewed as a smoothing filter with {HEAD ~ an input} at {TAIL ~ terminal} 15 
at
Alternatively L1 and D2 may be functionally viewed as a smoothing filter with { HEAD ~ an input } at { TAIL ~ terminal } 15
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH