[morzh]

OK, so with the 80 Ohm missing there should be other things too, like yje pilot lamp circuit, the 35Z5 connection.
Just trace it.

Now, the power to the heaters: I am not sure if this means "the heaters do not light up" or something else.
If the forme, keep in mind, that ANY filament being bad (open; it is almost bever short; filaments burn and open. Like ina lightbulb) will result in exactly this: no filaments light up.

1. Take out the tube, check EVERY filament for continuity. If you got no tube tester, use a multimeter. It is usually in tens of Ohms for 7-volt tubes. But there should be a reasonable (a few hunderd Ohm for a 50V tube to tens for 6-7V one) resistance.
2. Check your wiring. It is a daisy-chain.
3. I all is OK, clean (sandpaper, scalpel) your pins. Loctal are known for bad, bad oxidation.
4. Might as well clean the sockets. Be gentle. Careful application of Deoxit D5 (or a good contact cleaner) helps. Don't just spray it around, target to pins. or even put some in a small aluminum cup, use a sharp toothpick to dip in it and then push into pins' sockets.
Let dry before re-powering.

PS. It is a "warm" chassis set. Power it from an isolation transformer. Do not connect grounded devices to it (like a scope) unless the set is plugged through such a transformer.