SURROUND ENCODER CABLE (transformer)

CONSTRUCTING PATCH CORD A

  1. Schematic Diagram You will need the following in addition to the plugs and cables:
  2. Remember that when you are told: "DO NOT connect the shield" That it should be trimmed off and insulated with tape or shrink tubing to prevent contact.
  3. Find the marking that indicates the primary winding (usually a blue or black band).
  4. Mark the hot phase of each winding with a magic marker such that it can be seen after the transformers are mounted. If you can't determine phase, mark the diagonally opposite terminals of both transformers. IMPORTANT! Make sure each mark is on a different winding (use an ohmmeter), and make sure both transformers marked identically.
  5. Cut a number of equal lengths of mic cable long enough to easily reach from your SUB OUT and ENCODER RETURN connectors to where you plan to set the box. Leave 1 or 2 feet extra to allow for putting on the connectors, wiring the box, extra slack, and eventual repairs. You will need:
  6. Make holes in the box for grommets or strain reliefs, one for each cable you just cut. Make sure they will not interfere with mounting the terminal strips, PC board, or transformers.
  7. Schematic Diagram If using terminal strips, mount them to the box. If using a PC board, make mounting holes, but do not mount it to the box until told to. Make sure the transformers will not obstruct the mounting holes.
  8. Mount the transformers to the PC board or terminal strips. Be sure the transformer is supported by its mounting lugs, not the connections. Do not mount the PC board yet.
  9. Connect each transformer lead to a different circuit board pad or solder lug.
  10. Mark one transformer LEFT and the other one RIGHT.
  11. Decide on a color code for hot, cold, left, and right. Wire all plugs using the same color code.
  12. Connect a plug that fits your ENCODER RETURN connectors to ONE end of cable lengths you just cut as follows:
  13. Mark one of the connectors you just put on as LEFT ENCODER RETURN. Mark the other as RIGHT ENCODER RETURN.
  14. Schematic Diagram Connect plugs that fit your SUB OUT connectors to ONE end of each of the remaining cables:
  15. Mark one of the connectors you just put on as LEFT SUB OUT. Mark the other as RIGHT SUB OUT.
  16. Install the grommets, if used. Do not install any strain reliefs yet.
  17. Push the free ends of the wires into the proper holes in the box made to receive them.
  18. Schematic Diagram Connect the ENCODER RETURN cables as follows:
  19. Connect the SUB OUT cables as follows:
  20. Schematic Diagram Select the correct diagram for your mixer from this page, and compare it with the wiring you actually did, to make sure your wiring is correct. Correct any mistakes.
  21. Use an ohmmeter to make sure that parts that are not supposed to be connected together are isolated from each other. Also check across the transformer windings to make sure they have not been shorted out. A short gives a reading of 0, an open gives a reading of infinity (or very high megohms). The winding should give a reading which is somewhere in between - usually in the range of 50 ohms to 10000 ohms.
  22. Mount the PC board, if used.
  23. Install the strain reliefs, if used.
  24. Install the box cover.

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