Xref: utzoo rec.audio:5792 sci.electronics:2737 Path: utzoo!mnetor!uunet!husc6!mailrus!tut.cis.ohio-state.edu!ukma!gatech!mcnc!decvax!decwrl!pyramid!prls!mips!mark From: mark@mips.COM (Mark G. Johnson) Newsgroups: rec.audio,sci.electronics Subject: (here is) Nakamichi 410 schematic Message-ID: <2008@mips.mips.COM> Date: 9 Apr 88 05:39:23 GMT Reply-To: mark@mips.COM (Mark G. Johnson) Organization: MIPS Computer Systems, Sunnyvale, CA Lines: 60 ! ########################################################################## ! Line amplifier from Nakamichi model 410 audio preamplifier ! ! Node 1 = line level input (from selector switch), ! node 50 = line stage output, node 0 = system ground ! ! Power Supplies & local decoupling Vplus 80 0 10.0 ! Volts Vneg 90 0 -10.0 R81 80 81 33.0 ! Ohms R91 90 91 33.0 C81 81 0 470U ! (micro)Farads C91 91 0 470U ! ! Balance control: 100K pot, wiper = node 2 R2a 1 2 50K ! (kilo)Ohms R2b 2 0 50K ! ! Volume control: 100K pot, wiper = node 3 R3a 2 3 50K R3b 3 0 50K ! ! input stage: single ended with three *parallel* NPN's for very low ! noise operation C10 3 10 22U R10 10 0 330K R31 10 31 330.0 Q32a C=32 B=31 E=20 NPN TYPE=2SC1222 Q32b C=32 B=31 E=20 NPN TYPE=2SC1222 Q32c C=32 B=31 E=20 NPN TYPE=2SC1222 R32 32 81 820.0 R20 20 91 8.2K ! stabilization C31a 31 32 47P ! (pico)Farads C31b 31 20 150P ! ! Second stage: PNP with current source load Q40 C=40 B=32 E=81 PNP TYPE=2SA640 R41 81 41 15K D42 A=41 C=42 TYPE=1S1555 R42 42 91 100.0 Q43 C=40 B=41 E=43 NPN TYPE=2SC945 R43 43 91 1.2K ! ! Output stage: Quasi-complementary push-pull Q50a C=81 B=40 E=50 NPN TYPE=2SC945 Q50b C=50 B=41 E=51 NPN TYPE=2SC945 R51 51 91 10.0 ! ! Loop feedback network R50 50 20 1.36K R21 20 21 150.0 C21 21 0 470U ! ! ! that's all -- -Mark Johnson *** DISCLAIMER: Any opinions above are personal. *** UUCP: {decvax,ucbvax,ihnp4}!decwrl!mips!mark TEL: 408-991-0208 US mail: MIPS Computer Systems, 930 E. Arques, Sunnyvale, CA 94086