I picked up a Sentinel model 338 from a flea market for $20. I know im not supposed to plug in things this old into the wall, but i said what the heck since most radios usually work.

well, as expected (unexpected to an extent), there is no sound. not even a slight hum in the speaker (from possibly dry filter). im thinking loss of B+ or bad speaker.

anyone have a schematic to this unit they would like to share? its a 50B5 output.

Here you go: http://www.nostalgiaair.org/PagesByModel/188/M0018188.pdf

well i tested and got all my voltages, so i dont know what the heck is goin on. probably a bad coupling cap. theres only like 4 or 5 paper caps that need changed. if i have the antenna unhooked, i can hear a slight buzz in teh speaker. if i hook the antenna up, got nothing, dead audio. soooo probably a weak tube or so.