CHANGING THE TUBE
Your Tonebone has been designed to provide years of perfor-
mance before ever needing the tube changed. In fact, it is unlikely
that a tube change will be necessary for two to three years or more,
depending on use. Change the tube only when a degradation of
sound is noticeable.
Disassembly
1. Remove the rubber knobs by pulling them straight up. These
pressure-fitted knobs should be removed with care to avoid
damage.
2. Remove the nuts and washers securing the potentiometer,
footswitch, and input/output jacks using an open-ended wrench
or socket. Please use caution so as not to mar the finish.
3. Remove the 4 bottom screws that hold the top and bottom
chassis halves together. Carefully separate them. Note that the
chassis top and bottom fit snugly, so a little careful force may
be needed to clear the two side-mounted ¼” input and output
connectors. Watch you don’t lose the nylon washer between
the footswitch and the chassis top!
4. Remove and replace the tube. To do this, gently loosen the
12AX7 tube in the socket by wiggling it back and forth.
Reassembly
1. Install the PC board to the chassis top. Carefully align the
potentiometers, LEDs and footswitches with the holes in the
chassis and assemble through the top. Don’t forget the nylon
footswitch washer!
2. Attach the pot, footswitch washers and nuts (just finger-tight
for now), to allow alignment of the jacks when the bottom is
attached.
3. Carefully push the chassis bottom on, spreading the sides
slightly so as not to stress the side mounted ¼” input and
output jacks.
4. Attach the side ¼” jack washers and nuts. Do not over-tighten
the plastic isolation jacks as they can strip. Attach the 4 chas-
sis screws (don’t over-tighten). Now you can tighten up the
potentiometer shaft nuts.
5. Re-install the knobs... first rotate the potentiometer shafts fully
counter-clockwise. Place the knobs over the shafts so they
point to 7 o’clock and push straight down.
6. Test the pedal to make sure it works… plug in the power. The
LEDs should light when you depress the footswitches and you
can see the tube filament light up through the side vents.
Ready to wiggle tube out of the socket. 12AX7 tube replacement.
8
Radial Engineering
Classic Trimode
9
Radial Engineering
Classic Trimode
Ready to change the tube? Ok, lets
start here.
Knobs off, nuts & washers off, side jack nuts
& washers off, now remove screws.
True to the Music
True to the Music
Spread chassis sides to clear input &
output jacks.
Press on knobs with shafts counter-
clockwise and pointers at 7 o’clock.
TROUBLE SHOOTING
I am not getting any sound at all…
Start by connecting your
guitar directly to your amplifier & check each cable to make sure
they work. Make sure that these are plugged in correctly.
I am getting sound but no distortion…
Make sure pedal is not
connected backwards by reversing the input and output. If ok,
check tube. If the problem persists, see your Tonebone dealer.
The LEDs do not light up…
Check the power adaptor to make
sure it is plugged in. If the LEDs do not light up, check the outlet
with another device to make sure power is present. If they still do
not light up, check the power supply with a voltmeter.
The sound has changed, it sounds thin…
The tube may need
changing. Bring it to your dealer to have him test to make sure.
I am getting radio signals though my amplifier…
Cables and
bad grounding are usually the cause. Check amplifier is properly
grounded with a 3-prong A/C cord and wall receptacle is wired
correctly. Use high quality guitar cables with proper shielding.
P
HOTOS
OF
T
ONEBONE
C
LASSIC
