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I need to take my own suggestion and redraw the circuits for the RF
amplifier.
It is usual for schematics to show coils and transformers in the
order they are used in the bands but the S-85 seems not to. In
particular the two low frequency bands seem to be reversed. Looking at
designations for the parts and alignment data tends to confirm this to me.
If this is correct the third band down from the top of the
schematic is the lowest frequency band, i.e. the MW broadcast band.
Redrawing may make it clear what the resistor is. I can think of two
possibilities: one that is is to reduce gain. A common feature in
all-wave receivers since, at least in their primary market in the U.S.
signal strength on the broadcast band is often extremely high causing
overload and cross-modulation. Secondly; it may be to "spoil" the Q of
the resonator to broad-band it a little to improve fidelity. This is
also done fairly often in receivers with broadcast band capability. The
bandwidth can be increased a bit without reducing the image rejection
much. Neither of these may be the case but a circuit analysis will help
prove it.
I am sure Emmanuel feels as though we have stolen his ball and run
away with it. Perhaps he will have an insight as to the problem and
up-stage us all. What set me off was the suggestion that the design was
faulty even though its been used in at least two fairly mass-produced
commercial receivers. This still doesn't answer why the two bottom bands
don't work but redrawing the circuits may do that.
One can't ignore the converter stage either since if there is a
problem in tuning or the oscillator doesn't work the results in the
same, i.e. a dead or partially dead band.
Its always frustrating to encounter something like where the
equipment is very remote and one can't just have at it.

--
Richard Knoppow
Los Angeles
WB6KBL
SKCC 19998