I am needing filter match transformer T6 for a TR-4C if anyone has a parts radio that would sell one. I think it is the same as T13 that is also a filter match so I would take either one. If anybody has had any luck rewinding these I would take any advice on how you did it. May be able to fix mine. Mine is open on the secondary which looks to be about 6 turns. 73, Mark N5KJ