A.)Open main valve and evacuate unit to 0 mm (Torr). Close main valve. B.)Backfill with 2mm (Torr) of air. C.)Switch on bombarder and increase to 250 mA. Hold at this setting while maintaining pressure between 2 and 3 mm (Torr) with main valve. D.)When the unit is at 150C/310F, increase current to 300 mA. E.)Maintain pressure between 2 and 3 mm (Torr) with main valve. F.)At 200C/392F, reduce pressure to 1.5 Torr and increase to 350/375 mA. G.)When the electrodes are completely red and the glass has reached 230C/450F, switch off the bombarder and open the main valve. H.)With the main valve open, allow the tube to cool to around 50C/125F with a vacuum gauge reading less than 5 microns. I.)Fill the unit with gas.
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