about 5" over the edge of the work surface. Remove the Component
Board
two exposed screws from the bottom panel. Rotate the No. Function Numbering
console 180° and remove the remaining two exposed
A1 Input Controls (Ch. 1-6) 100s, 200s, 300s
screws. Lift the cover straight up. When clear of the bottom
A4 Equalizer 400s
panel, rotate it until the cover rests on its rear bumpers.
A5 Regulated Power Supply 500s
This "open clamshell" position, with the bottom panel
A6 Power Amplifier (2) 600s
horizontal and the vertical, cover provides access to all
A7 Output Connectors 700s
internal parts and assemblies (see Figure 1).
A8 Input Connectors 800s
When closing the console, reassemble as follows to
A9 Output Controls 900s, 1000s
avoid damage. Remove the air filter (if not already re-
All LED Board 1 100s
moved). Bend and position the wiring left harness to fold
on top of the PC board-fan assembly. Bend and position
A magnetic screwdriver is recommended for removing
the right wiring harness to fold between the fan and power
boards secured with screws. When removing front-panel
transformer, clearing fan blades. the Center the cover over
jack retaining nuts with a Y2" nutdriver or wrench, be care-
the bottom panel and lower the cover. With one side of the
ful not to damage the surface around jack. the Boards or
console extending about five inches over the edge of the
parts secured with nylon standoffs may be removed by
work surface, replace four screws and washers in the ex-
using a long-nose pliers to squeeze the locking lugs of the
posed bottom panel holes. Rotate the console so that the
nylon standoffs on the circuit board side, and sliding the
other side extends over the edge of the work surface, and
board outward and off the standoffs. The printed circuit
replace four screws washers. and Raise the front of the
board connectors be can reconnected for testing purposes
console so that it is sitting on the rear bumpers with the
after disassembly from the cover or bottom panel.
handle upward and replace the remaining screws and
washers. NOTE: The screw next to the left handle mounting lnput Controls (Ch. 1-6) and lnput Connectors Boards (A1
bracket does not use a washer. Replace the air filter. and A8): These boards must be removed at the same time.
Remove the knobs from the left (Input Controls) of the side
front panel. Remove the nine retaining nuts and washers
REVERB PAN
from the front-panel phone jacks (note that the HEAD-
To remove the reverb pan (AlO), disconnect the input PHONES jack-J815-has an insulating washer behind
and output leads from the reverb. Remove the screws and the metal washer.) Remove connectors J1 and J21 from
nuts holding the unit to the bottom cover plate. cover The the lnput Connectors board and connector J2 from the
plate and foam pads will remain in place. Secure the lnput Controls board. Remove connectors J24 and J25
replacement pan to the cover plate, making sure the side from the Output Controls board.
of the reverb with the phono jacks faces the front of the
Use a long-nosed pliers to release the locking lugs on the
console. Reattach the leads previously removed.
board standoffs. As each standoff locking lug is released,
If the console to is be operated with the reverb pan re-
push the potentiometer shaft in the vicinity of the standoff
moved, make sure the associated are leads not free to to disengage the board. Repeat this procedure each for of
short out any other wiring. Insulate tie and down the two
10 standoffs. As the lnput Controls board is disengaged
reverb cables and ground lead.
from the standoff, all the shafts pot except the six closest
to the lnput Connectors will board fall clear of the top
cover. Using the tips of the long-nosed pliers (or any blunt
PRINTED CIRCUIT BOARDS
object that will clear the pot clearance holes in the cover),
The console's printed circuit boards are mounted by
push the six remaining pot shafts through the top cover.
various methods. following The paragraphs describe the
After the lnput Controls has board been disengaged, free
best method of removing each board after cable connec-
the three phone jacks on the right hand side from the top
tors and connecting wires have been removed. IMPOR-
cover by grasping the body of the HEADPHONES jack with
TANT: When disconnecting cable connectors or soldered
the thumb and forefinger, pulling and downward until the
wire connections, make sure connectors or wires are iden-
bushing is free from the top cover. Repeat for the AUX
tified proper for reconnection. may This be done by affix-
INPUT 7 and AUX INPUT 8 jacks. Free the left side of the
ing a piece of masking tape marked with the reference
lnput Connectors board by inserting a medium-size screw-
designation (connectors) or terminal letter or color (wires).
driver between the input alignment bracket and the cover.
Start at Channel 6 and lift the screwdriver handle, freeing
the &pin connector and phone jack from top the cover.
Repeat for all six channels. When all six channels have
Similar wire colors are used in different circuits; been freed, the lnput Connectors board and the lnput
make sure proper re-connections can made. be Controls board may be lifted out for service.
Push-on connectors must be removed by pulling To reassemble, first make sure that LEDs the are prop-
straight out from printed circuit surfaces. board Do erly positioned. Position the lnput Connectors in the board
not apply side force removing when or reconnecting top cover (do not assemble nuts or washers at this time).
terminals, or damage may result. Position the lnput Controls at the board approximate loca-
tion of the standoffs. six The rotary shafts pot closest to the
front should be visible through their respective clearance
holes when viewed from the top of the cover. Reach
Refer to Figure 1 for the location of each board. The through the respective clearance holes from the outside
function of each board is given in the following table. of the top cover using a hooked tool (or a formed paper |