Alesis QS Series User Manual

Alesis QS Series Keyboards Service Manual V1.00 36 11/19/06
6.22 QS7/8 Main Revision C
Table 10 - QS7/8 Main PCB Revision C Changes
PART NUMBER: 9-40-1241 QS7/QS8 MAIN
CHANGES FROM REV: B TO REV: C
DATE: 5-7-96
CHANGE:
Change all text from Rev B to C
Move R88, R92, & C88 farther above central mounting hole
Tie both A.T. lines together before the CD4052 (U24)
Increase inner diameter of mounting holes to 160mil
Connect MIDI OUT/THRU barrels to chassis GND
Reroute \RD \WR \AS away from back panel jacks
Shrink inner diameter of PCMCIA mounting holes to 120mil
Change R2 & R3 to 120Ω
Connect MIDI IN barrel to chassis GND thru a 0.1uF cap
Connect LPF caps (C28, C31, C35, C36) in the MAIN/AUX OUT to chassis GND
Drop C74 and R75 (redundant to C70 and R73)
Edit text for first 4 ROMs by adding "A" to end of part number
Suppress U6 paste by renaming it V6 and suppressing in CAM
Add hole in bottom right corner to accommodate screw for mounting keyboard
Short thru R49 and U25D (connect input to GND) to EXT_IN
6.23 QS7/8 Main Revision D
Table 11 - QS7/8 Main PCB Revision D Changes
PART NUMBER: 9-40-1241
CHANGES FROM REV: C TO REV: D
DATE: 6-13-96
CHANGE:
Change all text from Rev C to D
Add 2200uF cap in parallel with C8
Change R37 into 1.2K 1206 5%
Separate Aftertouch lines into U24 Pin 4 & 5
Change R25, R24, R28, R27, R6, R7, R9, R10 into 15K
"U-connect" all tight pitch pads on uP and DACs
Lower R64 silk screen
Use New & Improved Fiducials
Connect all mounting holes to GND (on the Fly command)

Alesis QS Series Specifications

General

Multitimbral	16 parts
Oscillators	Sample-based
Effects	Reverb, Chorus, Delay, EQ, Distortion
Display	LCD
MIDI	In, Out, Thru
Memory	User Programs
Outputs	Stereo
Weight	11 kg