From the 1949 issue of BA catalog: Stancor A-3831, Primary 10M C.T.,40MA, Secondary 8/4/2. 5 watts, Suggested tube: PP30, 49. Cost $1.59 :-) > One of these animals has been grafted on to the audio deck of my "hangar > queen" R-390A, and I'm curious to know if it's a 600-ohm or a hi-Z > primary. >