A perplexing puzzle: National NC-183D power transformer

[jr_tech]

Originally Posted by dieseljeep

The transformer shown doesn't have enough 6.3 volt current capacity.

Even the 5 amp spec is a little on the weak side, as the heater currents add up to about 5.25 amps. I suspect that it is the same xfmr used in the 173 and 183 and a couple more tubes were added in the 183D (double conversion) design. No worry there, as xfmr ratings of that era tend to be quite conservative.

jr