Possible Error in "Analog Synthesizer 21st Century"

[fredw]

Page 3, Power Supply
Last Rev: July 24, 2006

The -15V supply is only connected to ground, instead of taking
a tap from the diode ring. Or, the diode ring is grounded, supplying
no voltage to the -15 regulator and associated components.

[Tim Servo]

Hi Fred,

Yes, that was an error in an earlier edition. Luckily it has been corrected in later editions. Other errors have been listed on E-M, but I thought I'd put them here in one place. Here's a compiled list of all known errors in AS21C:

1) Page 3 schematic: Junction of D2 and D4 should connect to the Input of IC2, NOT to ground.

2) Page 4 parts list: Listing for "C3 - C5" should be "C2 - C5." These parts are 0.01uF disk capacitors.

3) Page 5 schematic: 10uF electrolytic filter capacitors C7 and C8 should be labeled as C8 and C9.

4) Page 7 parts list: Listing for "R14 - R19" should be "R15 - R19." These parts are 10K resistors.

5) Page 11 parts list: Add "R51 2.2M" to parts list.

6) Page 17 schematic: Capacitor C6 directly above R17 and IC3d should be labeled as "C5 100pF." The correct C6 is around pins 6 and 7 of IC2b on page 16.

7) Page 18 parts list: Listing for "R75, R75" should be "R74, R75." These parts are 2.2M resistors.

Is it any wonder I have multiple proofreaders now? Like I said, all of these errors have been corrected for a while now, so anyone who has purchased AS21C since August of 2007 has all of these corrections. I apologize for the errors, and luckily they're easy to change in your book if you have an older edition. If you are unhappy with this, let me know and I'll replace your copy with a new one (if you bought a printed version, I'd ask that you mail back the old one). Above all, shout out if you have any other questions. I cruise here fairly often, or you can get me at magsmoke@gmail.com Thanks!

Tim (need to turn my internal Error Correction back on) Servo