| Hello Dimitrios   Polypropylene capacitors can actually self-heal to such an extent that 
there's little left of them. The melting point of polypropylene is not very 
high and they can end up as just a liitle blob of plastic.    Don't worry though, I still use them suitably rated for the frequency in 
use and most of them are 600Vac or more.   73, Hugh, M0DSZ 
  ----- 
  Receiving the following content -----  Time: 
  2019-01-31, 00:25:55 Subject: 
  Re: LF: TXing WSPR/MF on an indoor loop, part 2 
 
  Hi Stefan,
 In my experience these polypropylene capacitors when 
  they fail, they
 just lose some capacitance. I think they call it 'self 
  healing', maybe
 they imply that when they fail there is no short 
  circuit?
 
 I have some really nice silver mica capacitors (ex MW 
  broadcast stuff)
 that would be perfect for this task...
 
 Anyway, I am 
  slowly gearing up for some VLF action over here. The
 other day I did some 
  tests at 16.72 kHz into an ugly loop (very
 roughly 120 metres by 3 metres, 
  single turn) and I was able to receive
 my signals using an unoptimise 
  ferrite antenna at a bit over 2 km from
 the TX. I don't think I am in the 
  near field at that distance, am I?
 :-)
 
 73, Dimitris 
  VK2COW
 
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