Christer Andersson wrote:
Hello (V)LF experimenters,
I have an idea of resonating my existing vertical on 8 kHz.
Is there a practical way to construct a 600 mH loading coil, withstanding 3-4 A
and high voltage?
Any *large* toroids on the market?'
/Christer
sm6pxj
How about using salvaged cores from television line output
transformers? I can confirm they work well at 180 kHz, even they were
intended for LOPT use around 15 kHz. If required, use several cores
side by side to get a higher power rating (as do several ZLs). I would
also recommend a moderate air gap to assist with linear performance.
Thin cardboard about the same type as a QSL card is a starting point for
gapping cores :)
Regards,
Bob ZL2CA
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