Use the M4 (black) screws to install the sockets at the bottom of the top-panel.
3. Installing source selector and volume control
If you'd rather use a different volume control or attenuator to replace the one that comes with the
kit, make sure the volume control is not obstructed by the PCB underneath. However, you can always solve this problem with a bracket and entension rod
or you can salvage some scrap metal to hold the attenuator in position.
4. Installing power supply connector, fuse holder, RCA-jacks, and binding posts.
Refer to the marking at the back-panel and install them accordingly. Make sure the colour of the
binding posts and RCA-Jacks are positioned consistently.
5. Installing power transformers and output transformer.
Install these transformers on top of the top-panel and tighten the nuts. (It is not funny if they drop on your foot).
6. Installing the choke regulator.
Secure the choke regulator firmly inside the chassis.
7. Soldering components
Follow the markings on PCB and solder the components accordingly. As the rule of thumb, start from the lowest
component first (such as resistors), be aware of the polarity when you're soldering the electrolytic capacitors.
As for Auricap, even though they have no polarity on the capacitors it is advisable to follow
the manufacturer's instructions: the black lead is "in" and the red lead is "out".
Don't solder the preamp tube sockets onto the PCB yet.
Note: To avoid "dry-joints", make sure you heat the component leads and the soldering points together.
Apply solder and keep heating until it flows and covers both the soldering points and component leads.
(Be careful of your soldering timing. Don't overheat the components.)
8. Connecting the power supply
The 6.3V filament power supplies are the orange and blue (6.3V) pair of wires from the power transformer.
Use each pair of wires to measure the length require to reach the first tube filament pins.
Cut off the excessive length of the wires. Use the remainder of the wires to measure the required length to the next
connecting point. Make sure you twist each of the wires together before you solder them. This can effectively reduce the EMI.
If your kit includes tube rectifiers (5Z3), use the brown and green pair of wire from the power transformer
to connect to pin-2 and pin-8 of the socket. Connect the white pair of wires from power transformer to
pin-4 and pin-6 of the socket. Use the remainder of the white wires to connect to another 5Z3.
For kit without 5Z3, see picture below.
9. Building the support for bypass capacitor and resistor
Bend the tinned copper wire as shown in picture.
Solder the copper wire to pin-6 of the power tubes (V3 and V4).
Solder the bypass resistor to pin-8 of V3 and onto the copper wire.
Solder the bypass capacitor to pin-8 of V4 and onto the copper wire.
Connect pin-8 of V3 and V4 with a wire.
Repeat the same procedures for other channel.
10. Connecting the output transformer to the power tubes.
Isolate the Yellow-White and Green-Blue pairs of wires from the output transformer.
Connect the yellow wire to pin-3 of V3 and the white wire to pin-4 of V3.
Connect the green wire to pin-3 of V4 and the blue wire to pin-4 of V4.
Repeat the same procedure for the other channel. Be aware of the V3 and V4 position.
11. Connecting the preamplified signal from PCB to pin-5 of power tube
Use Kimber TCSS to connect to the pin-5 of each power tube to PCB (marked as "L-V3-5" and "L-V4-5" for left channel
"R-V3-5" and "R-V4-5" for right channel).
12. Connecting the choke regulator to PCB.
Solder the wire from the choke regulator to PCB (marked as an arch).
13. Connecting the AC power supply.
Twist the power supply wire (red) from the power transformer together and solder them to the power supply socket.
14. Connecting the source selector switch.
Use the screened cable (Kimber TCSS only long enough for one input) to connect the source selector and RCA jacks.
15. Connecting the volume control.
Use the ground wire (green-yellow or any colour you have left) for earthing.
Locate a main grounding point. The ideal location is somewhere between the power transformer and
the output transformer. Scratch off some paint until you can see the bare metal underneath.
Connect the following to the main grounding point.
Every point on PCB with "E" marking
Tinned coppper wire that supports the bypass capacitor and resistor
Output transformer (black wire)
Power transformer (black wire)
Power supply (from power socket)
17. Finishing touch.
Assembly the side and front panels
Attach the wooden panels with the wood texs provided
Install the perspex
Install the knobs
Leave all the vacuum tubes aside.
Put a 2A fuse into the fuse holder.
Turn the power on. Observe and confirm that everything is normal.
Test the voltage with a multimeter to confirm it is operating under normal condition.
Under empty load, the voltage reading may be 10-20% higher than the rated voltage.
If everything is ok, turn the power off. Insert all the vacuum tubes and
connect a pair of speakers to the output. Check the input impedance of your speakers and connect them to the 4 ohm or 8 ohm tapping accordingly.
You can also use a pair of 8-20 ohm power resistors as the load)
WARNING!!! Do not turn the power on with all the vacuum tubes inserted and
no load connected to the output. It may damage the output transformers.
Turn the power on.
Confirm all the vacuum tubes light up.
If there are any abnormallity such as tubes turn red, burned smell, smoke etc.
Turn the power off immediately. Find the source of the problem before turning the
power on again.
Steam engine noise
Wrong connection at the power tube and output transformer (Check the colour of the wires)
Swap the output transformer Yellow-White with the Green-Blue pair of wires
Anode turns red
R10, R11, R12, R13 open circuit or dry-joint
Resolder or replace those resistors
Very low sound level
R8, R9 open circuit or dry-joint
Resolder or replace those resistors
Sparking or cracking noise
Vacuum tubes not inserted probably or bad connection between the tube and socket
Reinsert the tubes or replace the tube or socket
When you touch the speaker binding post, it generates some noise. The output transformer "0" is not earthed properly