WhitakerAudio JC Whitaker 20 W Stereo Integrated Audio Amplifier, Manual

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WhitakerAudio
5.5.11.1 Output Transformer Secondary Connections
Examine the secondary leads from the two output transformers. There are four wires from each
device. Black is common and the other three leads provide for 4, 8, or 16 Ω outputs. In order to
optimize the amplifier feedback circuit, only the 8 Ω output is made available at the rear panel
terminals.
– Find the secondary leads from the right channel output transformer (T1). Trim the leads to
be about 3-inches beyond the expandable sleeving (approximately 8 inches total from the
transformer base). Attach a quick-disconnect connector to each of the four leads; include
the ground wire from the transformer case with the black lead.
– Find the secondary leads from the left channel output transformer (T2). Trim the leads to
be about 3-inches beyond the expandable sleeving (approximately 8 inches total from the
transformer base). Attach a quick-disconnect connector to each of the four leads; include
the ground wire from the transformer case with the black lead.
5.5.11.2 Speaker PWB Assembly
Find the speaker terminal PWBs. Two are provided—one for the right channel and one for the left
channel. Each board mounts on the speaker terminals for the respective channel.
Temporarily fit each PWB on to the speaker terminals. The board should fit tightly over the
posts. Upon completion the boards will be soldered to the posts. Note that it may be necessary to
trim the end points of the posts in order to provide for a good fit with the boards. Note also that
the right channel board is rotated 180 degrees relative to the left channel board.
Remove the boards from the chassis and perform the following steps.
– Using the technique shown in Figure 5.1, mount the 11 quick-disconnect posts on the right
channel speaker PWB. Solder.
– Using the technique shown in Figure 5.1, mount the 11 quick-disconnect posts on the left
channel speaker PWB. Solder.
– Install R13 – 8.2 k
Ω
, 0.5 W – on the right channel speaker PWB in the position “ Rfb ”.
Solder in place.