Many have had Beverage termination resistor fail due to nearby lightning
strikes. These parts are available at Digikey (digikey.com).
This component is a bulk ceramic resistor capable of absorbing 1400 joules
Ohmite AY151K "Pulse Eater" Bulk Ceramic resistor
150 ohms, 4.5 W (that's the highest value stocked at Digikey)
1400 Joules
Digikey # AY151K-ND
$13.66 each
Ohmite OA471KE Carbon Composition resistor
This resistor will take 30 kV before flashing over the outside
It will generally take 10 joules or more with a lightning waveform
470 ohms, 1 W
Digikey # OA471KE-ND
$2.03 each
A 'spark gap' arrester can be placed at the 9:1 transformer
This device is rated to clamp 10,000 amps
It is rated to fire at 75 volts. Sometimes the voltage can hit a few hundred
before it fires and drops to tens of volts. This is the 'lucky electron'
theory. No electron in the gap, no fire
Epcos EC75X, 75 volt firing voltage (higher voltages available)
Digikey # 495-1475
$1.41 each
Dave WX7G
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