W8KZW wrote:

The LMO is supposed to tune 500 KC - from X.0 to X.5. Mine
physically stops
at X.055 ... in other words, the counterclockwise "end of travel
thunk"
comes too early, and won't let me tune the bottom 55 kc of the band.
The
clockwise "end of travel thunk" comes where it should. These
"thunks" both
sound and feel the same .... as you would expect them to: solid and
defined, neither end like the feel / sound of a coil getting caught
up
inside a tube. The tuning is smooth and unobstructed across the full
range.

All told, I get around 432 kc of mechanical travel instead of 500 kc.

How many turns of the LMO input shaft does it take to go from end to
end?

The LMO output is supposed to be from 5.0 to 5.5 Mhz. Mine ranges
from
appx. 5.014 to 5.444 Mhz.

The readout is correct - a signal transmitted on 7.2 Mhz. is received
on 7.2
Mhz per the dial.

The construction of this receiver is about the best I have ever seen
on an
SB-XXX kit, so I don't think it's a question of shoddy craftsmanship.
Visual review of the mounting of the LMO, dial, knob, shaft, and
100KC
insert into the spiral on the back of the tuning dial all seems to be
perfect, with no obstructions showing anywhere.

So, that's what I'm looking at ... essentially a perfect LMO, but
with
abbreviated end-to-end travel.

If the shaft takes a bit more than 5 turns to cover the 432 kHz range,
the problem is electrical. But I doubt that very much.

If the shaft takes a bit more than 4 turns to cover the 432 kHz range,
the problem is mechanical. I think that's what's happening. The fellow
who suggested hardened grease or stuck disks is what I'd bet on.

The input shaft of the LMO turns *exactly* 100 kHz per revolution, and
turns a bit more than 5 revolutions stop-to-stop. That's the key to
knowing whether it's electrical or mechanical.

73 de Jim, N2EY