(Crosspost from the shoutbox, thought this might be the best place to ask after all.)
I am fixing a TDK ipod stereo thingy for someone, and a thermal fuse inside a PCB mount transformer has blown. I have swapped it out for a physically larger one - one with the same temperature specs, but higher current specs - all I could find.
Trouble is, I couldn't get all the EI laminations back in (got 21 of 24 back in), since the bobbin was a bit bulgy. What will be the result of this? Lesser efficiency, and therefore more heat, and so even more likelihood that the fuse will blow in the future? Hope not.
(At the very least I'd like to be able to run it for a while and measure the input/output turns ratio, so I can get a replacement.)
Cheers,
electronwaster
Edit: It passed a small smoke test. Connected to 18V rms input, gave 0.764V rms out, which is a ratio of 23.5, so for 240V mains, that would be 10.25V rms unloaded. So - I'm guessing a 9V AC transformer? Does that make sense?