User Manual

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Troubleshooting
When you have successfully finished assembling the unit, test its operation
while reading “Part Names and Functions” .
If you have found any problems with assembly or operation, use the
troubleshooting steps below.
Some parts are left over.
• The kit may contain some extra parts that are not used, such as resistors
or capacitors.
There aren’t enough parts.
• If you have lost some parts, contact us at www.nutekt.org.
• Also, contact us at www.nutekt.org if any parts were missing or damaged
before you started to assemble the unit.
I can’t assemble the unit, because I broke a part.
• Please contact us at www.nutekt.org.
The unit makes an abnormal sound when I tilted it or shook it after
assembly.
• A loose screw or other part might be left inside the unit. Open the lower
case and check the inside.
The volume or jacks are loose.
• Make sure that the nuts are fastened tightly. Remove the knobs from the
volume and retighten the nuts.
The sound is distorted.
• The input levels may be set too high. Adjust the volume level on the input
device.
A pop noise is heard when turning on the power
• This product makes a popping sound when the power is turned on, This is
not a malfunction because the muting circuit is not equipped in pursuit
of the superior sound. Connect a pair of headphones or the like to the
jack after you turn on the power.
Replacing the operational amplifier
The operational amplifier can be replaced with a DIP8 type operational
amplifier. The power supply for the OP amp is a 24–28 V single power
supply system. When replacing the operational amplifier, be sure that the
replacement uses the same rated voltage.
Replacing the operational amplifier with any other operational
amplifier besides the one included with this kit is to be done on your
own responsibility.
Use care when replacing the operational amplifier, so as not to bend
or break the legs.
Make sure that the components to mount are faced correctly when
replacing the operational amplifier. Install the pin #1 of the operational
amplifier (shown with a mark) so that it lines up with the dot on the
circuit board.
Specifications
· Vacuum tube: Nutube 6P1
· Connectors and jacks: IN jack (stereo mini phone jack),
jack (stereo mini
phone jack)
· Controls: Volume, NFB switch (internal)
· Output impedance: 10Ω; recommended load: 15Ω or greater
· Power: AA alkaline batteries (sold separately)
· Battery life: Approx. 9 hr. (using alkaline batteries)
· Dimensions (W x D x H): 111 x 65 x 29 mm / 4.37" x 2.56" x 1.14"
· Weight: 110 g / 3.88 oz. (without batteries)
· Included items: Owner’s Manual
* Specifications and appearance are subject to change without notice
for improvement.