Border Patrol Power Supply Installation Instructions.

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Model: Audio Innovations series 800mk3 /1000.

ELECTRICAL KNOWLEDGE IS REQUIRED IN ORDER TO PERFORM THIS CONVERSION SAFELY. POTENTIALLY LETHAL VOLTAGES ARE PRESENT. WE CANNOT BE HELD RESPONSIBLE FOR ANY ERRORS OR ACCIDENTS THAT MIGHT ARISE WHEN PERFORMING THIS CONVERSION. IF YOU HAVE ANY DOUBT ABOUT YOUR ABILITY TO PERFORM THIS CONVERSION SAFELY PLEASE CONTACT US FIRST

PLEASE READ THE INSTRUCTIONS FULLY BEFORE COMMENCING

KIT CONTENTS. POWER SUPPLY, 4 WAY TERMINATED CABLE, RUBBER GROMMET, CABLE GLAND, HEAT SHRINK.

TOOLS REQUIRED. SOLDERING IRON, PLIERS, M4 ALLEN KEY, SCREW DRIVER, SOLDER, ELECTRIC DRILL, 10mm or 13mm 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).

REMOVE THE VALVES NOTING THEIR POSITION.

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

Remove the coloured plastic sleeve from the on/off switch with a firm tug. Remove the 4 Allen bolts securing the lid and taking care not to damage the mains switch remove the lid.

Stage 1.
There are two green printed circuit boards inside the unit, a large full width board carrying the valve bases and a smaller board located towards the back of the amplifier carrying power supply components. Remove the four stainless steel screws which secure the small board to the electrolytic can power supply capacitors. Locate the 47ohm dropper resistor, de-solder it from underneath and remove it. De-solder and remove the two Red wires that come the from mains transformer to the back of the board. Insulate these wires with the heat-shrink provided. Do not remove or damage any of the other wires leading to and from the board.

Re-fit the board using only the screws for the rearmost capacitor. Drill a 10mm or 13mm in the underside or back of the unit and fit the rubber grommet or the cable gland supplied. You may find an existing hole which you can enlarge on the bottom of the unit. Be careful not to damage any internal components whilst drilling. Feed the supplied cable through the hole. Feed one of the left over stainless steel screws through the circular tag on the RED cable, through the PCB hole marked positive (+) and into the capacitor terminal of the foremost capacitor. Repeat for the GREEN cable with the circular tag through the PCB to the negative (-) capacitor terminal of the foremost capacitor. Screw down tightly ensuring that the tags do not touch each other. You have completed the attachment of the High Voltage supply.

Stage 2.

Solder the YELLOW wire to Pin2 of an EL34 valve base under the PCB and the BLUE wire to Pin 7 of the same EL34.  See diagram.
This completes the connection to the relay inside the off-board supply.

DANGER: Check that the two circular connectors on the H.T. supply are not touching each other.

Dress the new cables tidily and replace the lid. Replace the valves and the on/off switch sleeve and connect the newly installed umbilical lead to the off-board supply. Replace the mains leads to both units. Switch on the Audio Innovations 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

BorderPatrol Audio Electronics
c/o Kaja Music Systems   Waldorf  Maryland  USA

Phone/Fax +1 301 705 7460
E-Mail. bp@borderpatrol.net