01-06-2021, 12:25 AM
re above. I have broken the rule very many times over the decades, as did my father previously, (and experienced mysterious condenser failures) but when drawing sparks a moderate spark gap must be provided. On open circuit or long gap very high potentially damaging volts appear in both pri and sec ccts. Caution esp applicable with electronics (I have been told that many modern lawnmowers are damged by just one open circuit sequence.) To keep volts down a small gap was recommnded fro magnetos (The volts reqd to fire a normal or rich mixture are modest) I time 50s, 60s cars with crank handle by shorting the main ht lead and watching and listening for the break spark at points while hand turning.