User manual HAFLER DH-200

[. . . ] A combination of high performance, dependability, reliability, and moderate price is in the Hafler tradition of using the very latest technology to provide outstanding value. The DH-200 circuit is a refinement of the DH-200 design, a Hafler landmark which has achieved worldwide recognition, and has elicited glowing reviews since its 1979 introduction. As in the DH-110 preamplifier, particular attention has been paid to component quality, using polypropylene or film capacitors wherever feasible, for example, for superior sound. Combining the latest power MOSFET technology with uniquely simple and effective circuit topology reduces distortion of all types, and at all power levels, over the full audio frequency spectrum, to the vanishing point. [. . . ] Place this wire over the rear of the chassis. 24 C Prepare a 10" green wire and a 10" white wire. Twist these together with the ends even. Connect the green wire from the right to RS short lug #4. 25 0 Prepare two 22" white wires, and twist them together throughout their length. 8" in from one end of the pair, cut one of the wires, and unwind it about 11/2" in each direction from the cut. Strip 1/4" of insulation from each of these cut ends. Place the longer portion of the wire along the lower front edge of the chassis, with the break at the terminal strip TS. Connect the cut end from the left to TS lug #2. Connect the other end to the lower hole of TS lug #5. Place this pair along the front edge of the chassis, under the power switch, with the ends projecting from the front corners of the chassis. Install these in the capacitors, with the lugs pointing as in the diagram. Be sure this is the + terminal of the rectifier. (S2). 37 ·1 Remove all insulation from a 3" white wire. 38 [7 Select the power transformer, the 4 flat washers, and the 4 sets of #10 hardware. Position the transformer with the red leads to the center rear of the chassis, and the black and black/white leads towards the power switch. If the transformer is the special multiple voltage version, the additional leads should be placed as shown elsewhere in this manual for the desired line (mains) voltage. The red/yellow lead will likely be the correct length. If you wish to shorten the red leads for neatness in connecting them to the rectifier terminals, it is easier to strip them before the transformer is mounted. Place the white pair of wires under the front chassis lip. Install a flat washer on top of each transformer foot after the screw is inserted from below, and then add the nut. Be sure no wires are trapped. The transformer leads may be trimmed as desired for a neat job, but be sure you do not cut any of them too short (particularly if yours is the multi-voltage version, and any change to a different supply voltage is likely). [. . . ] The single green wire is to be connected near the center of the lefi circuit board to the hole designated "B", located just below the bias adjustment potentiometer. It must be securely soldered, but be careful that you do not damage adjacent components. Making sure that no wires are pinched between the module and the chassis in the process, reinstall the left module to the chassis with 4 sheet metal screws. Select the switch and its 2 nuts, lockwasher and indexing flat washer, and the switch mounting bracket. [. . . ]