PLEASE READ THE INSTRUCTIONS FULLY BEFORE COMMENCING


KIT CONTENTS. POWER SUPPLY, 4 WAY TERMINATED CABLE, RUBBER GROMMET/ CABLE GLAND, HEAT SHRINK, IEC MAINS LEAD.


TOOLS REQUIRED. SOLDERING IRON, PLIERS, M3/4 ALLEN KEY, SCREW DRIVER, SOLDER, ELECTRIC DRILL, 10/12mm DRILL BIT.


DISCONNECT THE AMPLIFIER FROM THE MAINS BEFORE BEGINNING. If the unit has been used recently, allow sufficient time for the power supply capacitors to discharge before beginning (5 mins is usually sufficient).


This is a two stage conversion. Stage 1 disables the on-board high voltage supply and connects the new off-board supply. Stage 2 enables the new supply to switch on and off from the amplifier.

Remove the bottom cover.

Stage 1.

The mains transformer and power supply PCB are located on the left hand side of the amplifier near the ON/OFF switch. Unplug the 2 RED wire carrying crimp connectors from the mains transformer. Insulate them with the heat-shrink provided. 

Locate the small inductor/choke  in between the mains transformer and the power supply PCB. De-solder the RED wire from the Right hand terminal (when viewed from the front)
Drill a 10mm hole for the grommet (or 12mm for the cable gland) in the back panel of the amplifier, near the IEC inlet. Fit the rubber grommet or gland and feed in the umbilical cable. 

Locate the two pairs of terminals for the large can style electrolytic capacitors. Connect the RED wire to the +ve terminal of the Right hand electrolytic (when viewed from the front) and the GREEN wire to the -ve terminal of the Right hand electrolytic (when viewed from the front). see diagram below.

This completes Stage 1.

Stage 2.
Solder the BLUE wire to Pin2 of one of the EL34 bases and the YELLOW wire to Pin7 of the same base. DO NOT REMOVE OR DISTURB ANY OTHER CONNECTIONS TO THESE POINTS. This completes Stage 2.

Dress the new cables tidily and replace the lid. Connect the newly installed umbilical lead to the off-board supply. Replace the mains leads to both units. Switch on the amplifier as usual. Your amplifier should now be ready to play. The valve supply will take longer to come up to operating voltage than the old supply but this will have the advantage of lengthening the life of the valves.