After i unwrapped the wire I didn't cut the wire till i checked the voltage first take turns off the transformer. just live the wire strung out in a pile. Hook a volt meter on each end of the secondary winding and keep checking the voltage
until you get it where you want it. As long as the wire isn't through the transformer window, it won't affect the voltage. if you need to go lower and you can cut excess the wire, scrape the varnish to hook up the voltmeter and check again. When you hook up the bridge rectifier the voltage will be higher. I think the transformer info told what percentage to lower the ac voltage. When i got the voltage where I wanted it I soldered the wire back on the terminal, rapped the cardboard cover around the windings, taped it . I didn't varnish it or anything.
Mine doesn't hum. That wire is heavy so it stays put really well. Hope this helps.
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