BTW, there was a radio builder company in Seattle WA in the late 1970s, i'm guessing, that made AM boat radios and mostly, aircraft HF SSB radios. Brelonix, it just came to me now. I have never heard tell of any of their A/C radios used anywhere in USA, never heard of one existing in USA, but there are internet mentions of it in other countries. How odd, i think. The common type Brelonix AM boat radio appears unused; maybe built too close to the 1977 shutdown of AM.