22E E Boards

Each of the signals from the guitar strings is independently amplified in the Hex Preamplifier Circuit on Board E. The six outputs of the Preamplifier Circuit are sent three places The Fuzz Circuit, The Trigger Generator Circuit, and the Audio Multiplexer Circuit. The Fuzz Circuit produces (if selected) clipped guitar signals to the guitar output. Since the Fuzz is created per string and then mixed, the effect is a 'clean' distortion with low intermodulation distortion. The Hex Guitar outputs...

24 Table of Control Signals Used in the Extraction Process

CONTROLS E' EXTRACTION STARTS E' FIRST MODE EXTRACTION ENABLES OR STARTS E' EXTRACTION. DENOTES START EXTRACTION EXTRACTED GUITAR SIGNAL (SQUARE WAVE SENT TO BOARD D). HOLDS A GATE LOW FOR DURATION OF EXTRACTION DENOTES EXTRACTION OCCURRING CONFIRMS E' HAS OUTPUT DENOTES E' HAS OUTPUT TRANSFERS DATA TO SHIFT REGISTERS ON D BOARD

32 Board B

The sample and hold circuit provides a DC voltage output by sampling and storing the instantaneous voltage level of signals on its input each time a trigger pulse is provided. This stored voltage is held until the next trigger pulse occurs. Signals which are to be sampled and applied to pin 3 of Z1A. Z1A amplifies and buffers the signal and supplies it to 01. When a trigger from either the LFO or the guitar string is received through C3, 01 conducts just long enough for the memory capacitor...

34 Board D

Z6, R3, R4 and C7 are the 1 MHz oscillator. Z5A and Z5B divide this frequency by four to produce a 250 KHz clock signal. The 1MHz signal is used primarily to clock the Output Counter Frequency Synthesizer Circuit. The 250 KHz signal is used to clock the input counters and the shift registers on initial string plucks. Z2, R1, R2 and C4 are the 1 KHz oscillator. Z7A and Z7B are used to synchronize 1 KHz clock with the high frequency clock. This synchronization also insures that the 1 KHz will not...

Pulse

UNLESS OTHERWISE SPEClPlEDi RESISTOR VALUES ARE IN OHMS CAPACITOR VALU HS A e IN < p PiCOPARADS) DIODES ARE IN4I4 C17, CR Oy QIO, 511, Z.< i RED NUMBERS INDICATE THE LOCATIONS OF BOARD - TO BOARD CONNECTIONS SEE PAGE 28 FOR FURTHER EXPLANATION. CAPACITOR VALUES ARE IN yuf (P - P COFARADS)

Test Patch Set Up

Sliders and switches not illustrated should be all the way down. 1. Trigger sensitivity maximum.- 2. Trigger sensitivity minimum.- 2. Put Envelope Follower Select Switch in PEDAL position. 11.5V (typical) OV (typical) 1. Depress the system ON OFF Button. 1. Initial Frequency sliders midposition. 1. Initial Frequency sliders midposition. 1. Initial Frequency sliders midposition. 1. Initial Frequency sliders midposition. 1. Initial Frequncy sliders midposition. 1. Initial Frequency sliders...

Trim Procedures

5.1 Power Supply (NOTE These trims should always be executed first.) 1. Monitor the Power Supply's +15 volt output with a digital voltmeter. 2. Adjust R19 for exactly +15.00 volts. 2. Put the digital voltmeter's ground lead on the Power Supply's -15 volt output and put the meter's plus lead on the Power Supply's ground output. 3. Adjust R20 exactly +15.00 volts (reversed polarity).

44 Board D

T high E ,75ms Pulse Width 1 yus E high 2V B 1,6 V G 1.3 V D 0.9V A 0.5V E low OV J2E-1 High E J2E-2 B J2E-3 G J2E-4 D J2E-5 A J2E-6 Low E Pluck each string and monitor the corresponding test point location. EH2 High E B2 B G2 G D2 D A2 A LE2 Low E 1. Pluck each string and monitor the corresponding test point location. Guitar Output Jack, Left Output Jack, HEX MIX OUTPUT, LEFT & RIGHT OUTPUT 1. Plug foot switch into Sustain. 2. Pluck string and depress foot switch. E' module pin E' module...

31 Board A

Shift registers Z5 and Z6 are used to digitally generate a random noise source which is filtered and buffered by Z7 to produce a pink noise signal. The Special Effect Select switch, switches either pink noise or the mixed guitar signals to Board C. The Control Voltage Buffer is a high input impedance FET input op amp. It is used to add portamento (a voltage lag) through the use of R1 and C14. The control voltage output is supplied to Boards B and C via the CV INPUT and OUTPUT jacks on the rear...

36 Power Supply

Z1 contains a voltage reference which supplies approximately +7 volts to pin 6 of Z1. This voltage is connected through pin 5 to the noninverting input of an op amp. The output of the op amp is connected to an emitter follower, also located in Z1, which controls the pass transistor (Q1). Should the output of the power supply change, the voltage at the junction of R11 and R12 will supply the inverting input of the op amp in Z1 with the voltage difference. The emitter follower and pass transistor...

52 Board B

Monitor TP-5 (square wave output) with an oscilloscope. 3. Adjust the VCO 1 (or VCO 2) Coarse Frequency Slider to display exactly 1 complete cycle. 4. Adjust the 50 PULSE WIDTH trimmer until waveform duty cycle is exactly square (50 ). 1. Monitor TP-5 in VCO 1 (or VCO 2) with an oscilloscope or a frequency counter. 2. Put the VCO 1 (or VCO 2) Coarse Frequency Slider DOWN fully. 3. Put the VCO 1 (or VCO 2) Fine Tune Slider exactly in the MIDDLE. 5. Adjust the VCO CAL trimmer for a 50 msec,...

Arp Avatar Repair

3.3.1 VOLTAGE CONTROLLED FILTER (VCF) Audio signals from the VCF are processed by the high pass filter (C3, R13 and R74) and connected to the noninverting input of Z2. Z2 is an operational transconductance amplifier (OTA) whose gain is a function of the current signal supplied to pin 5. Control voltages from the two envelope generators and the VCA gain slider are connected to Q1 which supplies current to the OTA. R70, the control reject trimmer, balances the inputs of the OTA to minimize the...

21General

The Avatar's Extraction CV circuitry is divided into two basic sections E and E' Boards, and D and D' Boards. The E E' Boards contain the analog extraction portion of the instrument. Six audio signals from the ARP Hex Pickup are supplied to the E Board. The output is an extracted pulse wave at the frequency of the last string plucked. This signal is only gated out when the E E' circuitry is sure the signal is valid. The D D' Boards accept the extracted pulse wave from the E E' Boards and...

23 D D Boards

Hexaphonic Pickup

Boards D and D' accept a clean pulse wave from the E' Board, store it in memory, and then produce a control voltage to drive the synthesizer portion of the instrument. The memory feature of the circuit is used to produce continuously a valid control voltage even in the absence of a pulse on the input. The memory feature is also useful for masking the flatting effect caused by the release of a fretted string and other pitch inconsistencies typical of guitar signals which would otherwise cause...

String Sensitivity Trimmers Test Set Up Patch

Mot Passe Sony Vpl Es2

ALL SLIDERS AND SWITCHES NOT ILLUSTRATED SHOULD BE ALL THE WAY DOWN. - ' I ---' ' r ffiV 1 III Il 1 , ' gt . . .V. -. . ' . gipplp - ATE OUT ATE M Tfi OH T AJO CATES S' fJAL FLOiU A TC 80ARD . ' ., - . SEMH SH TCH COMMECT OA S E BOTTOM LEFT OF DPAW AJ . AVATAR MODEL 2223 INTERCONNECTION DIAGRAM E38 GATE Di D, De JlA-12 JlA-ll JIA'I JlA-1 1. uuless otheevoist speof fc '. all reststoe. val oes gt m ohv s all capaotoc values ape vm p piccfafcads' 12 ' o covjve gt 4t oki osed fdp suppl-r volta e...

Assembly Board B

Arp Avatar Cable

RED NUMBERS INDICATE BOARD - TO - BOARD CONNECTIONS. SEE PAGE 28 FOR FURTHER EXPLANATION. . UA L amp 5S OTHEWSe srecirieb-ALL S STO.C AJ O HS lu. lt I IPACI gt -QPS stet v uf CP ptCOFAeAbi S. H' H ST eer es cz l1 j3d , r i, 2 21 3. co v i gt y r o v L sab fou slipplv voltage RED NUMBERS INDICATE BOARD - TO - BOARD CONNECTIONS. SEE PAGE 28 FOR FURTHER EXPLANATION. MOTES'. I. UklLESS DTHEtWSE 5PEC FIEty. V-- PICOFARADS ALL DlODES ARE IM4I4S Z. HIGHEST REF DEV.C73, CTJ2S, J lt iE.,Vll, Q4-, 1222...

Avatar Model 2223 Wiring Diagram Power Supply

Sn74ls02n Schaltplan

AVATAR MODEL 2223 ASSEMBLY POWER SUPPLY ' AMP DUAL ' AMP QUAD NORTON IC QUAD COMPARATOR C OP AMP FET C 5V REGULATOR C 18-STAGE STATIC SHIFT REG C CMOS PAIR PLUS INVERTER IC DUAL 'D' FLIP FLOP SET RESET IC DUAL 4-STAGE STATIC SH REG IC GATE QUAD EXCLUSIVE-OR D-TO-DEC. DECODE DRIVER POT SLIDE AUDIO 1M, POT SLIDE 100K AUDIO CAP TANT 1UF 35V 20 CAP TANT 10UF 35V 20 SWITCH SLIDE DPDT SWITCH SLIDE DP3T SW MOMENTARY CONTACT PB 3-PIN CONNECTOR RECP SOCKET DUAL IN LINE 16-PIN CABLE 16-PIN REFERENCE ARP...

Foot Switch Jacks

Arp Foot Pedal Expression

ARP Foot Switch V4 stereo jack, tip and ring normally closed ARP Filter Foot Pedal stereo jack to 100K and taper potentiometer in pedal Enables triggers from Trigger Generator Circuit to enter Trigger Select Circuit Allows user to select which of the six strings can control the synthesizer. Routes either pink noise or guitar signal to Board C. Allows the guitar signal straight or fuzz to be processed through the VCF, in addition to the VCOs. Adds a lag or delay to the string control voltage....

11 Introduction

The AVATAR is divided into two sections Synthesizer and Pitch Extractor CV Generator. The Synthesizer section is like the ARP Odyssey in fact, the AVATAR and Odyssey use several of the same printed circuit boards . It consists of two voltage controlled oscillators, a voltage controlled filter, a voltage controlled amplifier, two envelope generators ADSR and AR , a low frequency oscillator, and a sample and hold circuit. As with standard keyboard synthesizers, the synthesizer requires a 1 V...