I added a color-coded block diagram to my site. No cost download at: https://wd0gof.com/hallicrafters-radio/technical-discussions/sr-2000/ CLICK ON "BLOCK DIAGRAM" Walt Cates, WD0GOF https://wd0gof.com/Hallicrafters A majority of acceptance is not proof of correctness. https://wd0gof.com/bible-study/commentaries/