Really stupid question: When checking resistors while restoring an older
receiver, is it common to attempt to check the resistor while it is in the
circuit? That is, make a guesstimate of the parallel resistance (working
from the schematic). Or, should I disconnect one end of each resistor to
check it?

(Am working on an S-85. Have replaced most capacitors. No hum and the B+
voltages are OK, so the original power supply capacitors seem OK. General
sensitivity is still low, so resistor checks seem to be next on the list. IF
and RF alignment are OK. The last owner had the local osc above the signal
on band 4, which was the only serious problem. Tubes are OK, I think.)

Why an S-85? It was my first receiver, way back when (with a Heathkit Q
multiplier).

Bill - W2WO