Hi all,
I have a few mica capacitors that came from a MW broadcaster, similar
to this one (in fact I have one that it bigger than this one).
Stefan, I think this is probably your best bet and pity you are not
closer otherwise I would be happy to lend you a couple to do your
experiments :-)
https://rustys.net.au/products/large-ducon-transmitter-honey-pot-capacitor
(this is smaller than the ones I have, most are about 1 nF capacitance)
73, Dimitris VK2COW
Στις Πέμ, 31 Ιαν 2019 στις 10:01 μ.μ., ο/η dhchurch
<[email protected]> έγραψε:
>
> 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 -----
> From: Dimitrios Tsifakis
> Receiver: rsgb_lf_group
> 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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