TU-879S  Stereo Tube Power Amp
TU-879S allows you  to use  KT88, KT66, EL84 (6CA7)  power tubes without any remodeling.   (Replacement power tubes are not included)

Ready to Assembly

  • Soldering Iron(φ0.81.0mm)
  • Solder iron stand
  • Diagonal cutter
  • Long nose pliers
  • Screw driver
    (No.1 and No.2)
  • Hexagonal wrench (1.5mm~2.5mm)
  • Pen knife
  • Scissors
  • Oil base marker
  • Nut driver (5.5mm)
  • Multimeter (optimal)

TU-879S Step-by-Step Assembly Instructions

  • Check the parts list included in the kits before you proceeding to assembly.
  • On the soldered side (side with copper foil) of PCB A, there are 3 holes with arrows indicated. Use solder plating for the 2 holes with copper foils.
  • Install the metal oxide film resistor 2~3 mm above the Printed Circuit Board to diffuse heat.
  • Cut 7 strands of tin-coated wire 6~7 in length. Put a strand of tin-coated wire into a plastic tube and bend the wire to the same shape as the image shown. The total length of the tin-coated wire should be 35mm. Solder the jumper wires onto PCB the same way as the resistor.
  • The fuse holder is installed in the soldered side of the PCB.
  • For detail installation, please refer to assembling instruction manual.
  • 12 out of 15 base pins are installed from the soldered side.
  • Put the PCB on a piece of cardboard when installing the pins.
  •  Use long nose pliers to insert the pin. Solder the base pin on OPT1 & OPT2.
■Photo 6A
■Photo 6B
  • C1112141617 are Electrolytic capacitor. The capacitor is installed as shown in the photograph.

    For detail installation, please refer to the assembling instructions manual for additional details. 
    ■Photo A
  • Put the leads and body of the capacitor through PCB from the solder side.
    ■Photo B
  • Level the capacitor to the same height as C3, 4, 9, 10.
  • Insert C13 and 15 on the soldered side of PCB and station the capacitors with double sided tape.
  • Line up the 3 legs of FET with 3 base pin on the PCB and solder in between
  •  Use screw to station the FET onto the spacer when soldering.
  • After soldering the FET in place, remove the screw on the FET.


  • Match the arrow on PCB A with PCB F and position it with a screw.
  • Match the hole in the middle of V2 and V3 socket with the indicator on the PCB and solder.
  • After soldering, remove the screw on PCB F.
  • Remove all washer or nut from the toggle switch.
  • Make sure the switch is pointing straight up before soldering.
  • Install toggle switch (SW1) onto PCB C  with soldering side facing up. Repeat steps for SW2 on PCB D.
  • Cut a piece of tin wire and put it through the two J8 holes and J9 holes. (page 6)
  • soldered the 3 jumper wires  onto PCB the same way as indicated. Use oily marker to mark the installation position as necessary.
  • As for wiring of the power transformer, twist the same colour cords together and put the wires through the hole on PCB A. Then, solder the wires on PCB A  (Page 6)
  • The PCB A and power transformer are screwed in the shield panel.


  • Solder the 6 wires coming out from the volume control on PCB A onto PCB E according to the marked arrangements.
  • After installing the transformer, twist the red and orange cords together and put them through  the hole on the main chassis.
  • Solder the red and orange cords from the output transformer onto the base pin labeled OPT1(L), OPT2(R) on the circuit board. Use pliers to bend the end of the wire into a J-shape and hook it onto one of the base pins. 
  • Additional detail can be referred to page 12 of the installation manual.
  • If the front panel and insulator are installed in the chassis and the vacuum tubes are installed, the amplifier is completed.
  • Let's enjoy the wonderful music from this cutie.