Wow, the more I look at this guy the more I see what a hunk of crap it is.
It does seem to use 25Hz AC, and it uses a ballast tube! This one is encased in glass. It's an energy waster. It's an M55HG. Also, it's a TRF set, and because of it runs on 25Hz power, it's electrolytics are meaty too. Some googling indicates it's a clone of a Silvertone 7213. Looking at the Silvertone schematic, it is. The Air King 2206 was the 50-60Hz model, which the Silvertone 7213 is it's clone (or visa versa). The Air King 2207 must be the 25Hz model. Should I replace the ballast tube with discreate resistors? Can I power it with 60Hz from the wall? Am I wasting my time with this set?
Thanks.
Jonathan