I have a few 30B transformers. I’ve always loved these things, not sure why but I do. Anyway, to the point of my post, I’ve noticed that many of them are 18V output, but then others are only 15V.
What’s up with that?
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The factory literature and the Factory Repair Manual show the 18B and 30B as 18v. Almost all other postwar Gilbert transformers are either rated at 15v or 16v. The 22035 and 22090 are rated 17v. The actual output is a function of the input line voltage. The Gilbert output ratings were many times unclear on the tested input voltage. Many transformers listed an input range of 110v to 120v for the wattage rating but were silent on the resulting output voltage.
Are you referring to the measured voltage across the base post and fixed voltage terminals or the labeling?
Labeling. All of my 30Bs are listed as 18v on the back. They usually measure between 18.9 and 19.3 unloaded. However, I’ve seen plenty of 30Bs at auction and at shows that have a label on the back that says “15v”.
Thanks. I have looked at 30B's at train shows but never paid attention to the label.
