GE L-660 tubes don't work.

[Electronic M]

Antiquated wireing errors do happen. I bought and sold a late 40's Crosley it had hum and all-original caps, except for the filter cap which was a 50's-60's replacement. Well the origional was wired in wrong I replaced it the same way they did, and it still hummed. I didn't have a schematic for it, and coulden't figure it out so I sold it. The next owner informed me what was wrong.