W8KZW wrote:
Before I tear this thing apart, I thought I'd "go to the well" to see
if
anyone has had the same problem.

I acquired an exceptional SB-301, but the tuning range is restricted.

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.

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.

My hope is that I'm just missing something stupid, and it is pointed
out to
me so I don't completely disassemble the unit if I don't have to.

Thanks in advance for the input.

73,
Jeff
W8KZW

Jeff, I don`t have the Schematic in front of me, But, If you will look
at the oscillator circuit of the pto you will probably find a variable
inductor and a fixed capacitor in parallel with it ,forming a tuned
circuit..you will probably find that the fixed cap has changed
value..try changing the value of the parallel cap to about 5% less.Then
the inductor will probably reach its normal tuning range.. I would
remove the PTO (if it`s not too difficult)and run it on the bench until
you get it sorted out .. Good Luck Harold W4PQW