[Radioroslyn]

Looks like it's a 1.8ohm resistor. As for the motorboating since it not in the af amp I would track it down by grounding the control grid of each stage though a .1 cap until it stops. Af amp is ok so you don't have to do it there but I would suspect the IF stage for starters. Once you find the stage that is motorboating then check the screen bypass and the bypass on the b+ before it goes into the IF transformer. Did you dittle with the trimmers on the IF cans?
Terry