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Boater Sam · 16th May 2018, 6:48 pm

An arduous and frustrating day, unwinding and counting the turns on the intervalve transformer bobin, all 13000 of them!
The 46 swg wire is just too fragile to put the bobin on the winder and pull it off so it had to be done manually.
Not surprised that it was open circuit, green spot corrosion at both ends of the bobin core, multiple breaks as it unwound, and it was wound very tightly against the end cheeks.
If anyone wants to know, the tap is at turn 4440, it's an auto transformer.
Not much progress to show really for a whole day, fortunately it's not a paying job. New wire on order, it will go on easier and faster than it came off.

16th May 2018, 6:48 pm	#14
Boater Sam Banned Join Date: Dec 2013 Location: Middlewich, Cheshire, UK. & Winter in the Philippines. Posts: 3,897	Re: Cossor old confusion. An arduous and frustrating day, unwinding and counting the turns on the intervalve transformer bobin, all 13000 of them! The 46 swg wire is just too fragile to put the bobin on the winder and pull it off so it had to be done manually. Not surprised that it was open circuit, green spot corrosion at both ends of the bobin core, multiple breaks as it unwound, and it was wound very tightly against the end cheeks. If anyone wants to know, the tap is at turn 4440, it's an auto transformer. Not much progress to show really for a whole day, fortunately it's not a paying job. New wire on order, it will go on easier and faster than it came off.