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Old May 3rd 04, 04:20 PM
Alun
 
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"KØHB" wrote in news:Tqslc.3830$Hs1.3291
@newsread2.news.pas.earthlink.net:


"Griff" wrote


However, I am a bit puzzled by his summing-up quote for this chapter:
"Regardless of the thickness of the wires and the high levels of
voltage, telegraph wires simply couldn't be continued indefinitely".
Now I would have thought the restriction was *exactly* due to the
limitations on wire thickness and voltage (ie the practical problems
with manufacturing telegraph cables and voltaic cells at that time).
Or am I doing Mr.Petzold an injustice, when perhaps there was some
other limiting factor ?


Probably due to the cumulative C and L of a long wire eventually shaping
the waveform so that rise and fall profiles are smeared.

73, de Hans, K0HB






I beleive they used to add inductors to telegraph wires at intervals before
they had repeaters. This seems counter-intuitive to me, as I would have
thought the L was more of a problem than the C. Does anyone know the
correct explanation?

Alun, N3KIP