If you measure the gauge of the wires on the primary, and its resistance, you can calculate the number of turns pretty accurately.
Assuming that the secondary has gone open or shirt circuit, you won't be able to apply the same there, but it doesn't look like it would be too hard to disasseble the cores. Given the (visual) guage of the wire relative to the coil, it wouldn't be too hard to estimate -- or even tease apart and count -- the number of truns in the secondary.
All that is then left is the tertiary tap. That would require unwinding -- counting as you go -- to find where the tap tees in. Having done that, you could purchase the right gauge wire and rewind it.
Thank you all for your gracious help. Nigel for suggesting the website and JimB for going the extra mile to provide more insights and recommendation. Thank you Bud as well but to be honest I can’t trust myself to perform what you outlined accurately haha. You are clearly more “experienced” than me on this. I’ll give the 75VA a go and post here when I have it installed. That’s assuming I can figure out how to wire up the transformer!
Hi JimB,
I wanted to just double check. The link you had included for the 75VA is for a 230V transformer right? I would need to find one similar but for 110V right?
Hi JimB,
I wanted to just double check. The link you had included for the 75VA is for a 230V transformer right? I would need to find one similar but for 110V right?
It's unlikely to help - a cooked transformer will fry until the primary dies, even if the secondary has the shorted turns, and measuring the resistance of the coils isn't going to be very informative.
More of an issue, and well worth testing, is what the transformer feeds - in case the rectifiers (or something else) has gone short - you would expect there to be a fuse, but there might not be, and they may depend on the transformers internal thermal fuse to blow in case of a secondary failure.
It's unlikely to help - a cooked transformer will fry until the primary dies, even if the secondary has the shorted turns, and measuring the resistance of the coils isn't going to be very informative.