Shure SR105 manual

SR105 Power Amplifier OPERATION AND SERVICE MANUAL Manufactured by SHURE BROTHERS INC. 222 Hartrey Avenue Evanston, Illinois 60204 U.S.A. WARNING To reduce the risk of fire or electric shock, do not expose this appliance to rain or extreme moisture. Copyright 1979, Shure Brothers Inc. 27A888 (SJ) (95B652) Printed in U.S.A.[...]

SR105 Power Amplifier SPECIFICATIONS The following specifications apply to both SR105A and SR105B Power Amplifiers except where noted. The SR105A Power Amplifier provides both direct-coupled speaker output and transformer-coupled, constant-voltage, 70-volt output. The SRlO5B Power Amplifier is equipped for direct-coupled speaker output only. ......[...]

SR105 Power Amplifier SPECIFICATIONS (Curves shown are typical) FREQUENCY (Hz1 OUTPUT POWER (WATTS) TOTAL HARMONIC DISTORTION VS. OUTPUT POWER TO 4-OHM LOAD AT 50 HZ, 1 KHZ & 10 KHz (DIRECT OUTPUT ONLY) OUTPUT POWER VS. FREQUENCY AT 1% 81 2% TOTAL HAR- MONIC DISTORTION TO 4-OHM LOAD (DIRECT OUTPUT ONLY) LOAD RESISTANCE, OHMS OUTPUT POWER (WATTS[...]

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SR105 Power Amplifier TABLE OF CONTENTS Section Page ............................... SPECIFICATIONS ii DESCRIPTION .................................. 1 OPERATING INSTRUCTIONS ........................ Functional Identification 3 .................. General Operating Instructions 3 ........................ Mounting and Ventilation 4 Thermal Overload .[...]

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SR105 Power Amplifier DESCRIPTION (Shown in A105A Carrying Case) The Shure SR105 Power Amplifier is a high-power ampli- fier designed for sound reinforcement applications. It is capsble of delivering 200 watts rms to a 4-ohm load, and is available in two models, the SR105A and SR105B. The SRlO5A Power Amplifier provides both a direct-coupled speake[...]

FIGURE 1. SR105 POWER AMPLIFIER FRONT PANEL FIGURE 2. SR105 POWER AMPLIFIER REAR PANEL (SR105A MODEL SHOWN)[...]

SR105 Power Amplifier OPERATING INSTRUCTIONS FUNCTIONAL IDENTIFICATION (Refer to Figures 1 and 2, Page 2). 1. OUTPUT VOLTAGE Meter - lndicates Amplifier out- put voltage in percentage of maximum voltage. 2. VOLUME Control - Controls Amplifier output level. 3. THERMAL OVERLOAD Indicator Lamp - lndicates Amplifier shutdown due to excessive heat sink [...]

MOUNTING AND VENTILATION The SR105 Power Amplifier is designed for rack-mount- ing in a standard 19-inch (483 mm) audio equipment cabinet rack and is supplied with the necessary mounting hardware. To insure adequate air circulation, a minimum clearance of 51 mm (2 in.) should be provided above and behind the Amplifier (see Figures 3, Page 4). If th[...]

FIGURE 4. SR105 POWER AMPLIFIER BLOCK DIAGRAM METER RECTIFIER In applications where the Amplifier is located at a con- siderable distance from the mixer-preamplifier, electrical interference or excessive hum pickup may be encountered. Hum pickup may also be encountered over shorter distan- ces as a result of ground loop conditions between the units[...]

FIGURE 5. INPUT CONNECTIONS @ UNBALANCED PARALLELED MIXER- PREAMPLIFIER POWER AMPLIFIER 0 I I I I I / A 0 UNBALANCED PARALLELED HIGH-IMPEDANCE INPUTS A TO POWER AMPLIFIER - - OR HIGH-IMPEDANCE OUTPUT CONNECTIONS Four standard 1/4" phone jacks (8) and one two-terminal barrier strip (9) on the rear panel of the Amplifier provide direct-coupled[...]

2 3 4 5 678910 20 30 40 LOAD IMPEDANCE (OHMS) FIGURE 6. TYPICAL OUTPUT POWER VS. LOAD IMPEDANCE FROM 2 OHMS TO 32 OHMS I1 KHz. 2% TOTAL HARMONIC DISTORTION) (DIRECT OUTPUT ONLY) tection circuitry and cause low-frequency breakup or dis- tortion of the Amplifier audio output. The 70-volt output of the SRlO5A Amplifier is trans- former-coupled to faci[...]

AMPLIFIER-TO-SPEAKER DISTANCE (FEET1 200 400 600 800 1000 1200 36 - 32 0) i 28 Y 2 24 Y 0 1 20 P 3 16 L J I2 0 8 4 0 50 100 1% 200 250 300 AMPLIFIER-TO-SPEAKER DISTANCE (METERS1 FIGURE 8. RECOMMENDED WIRE GAUGE VS. AMPLIFIER-TO-SPEAKER DISTANCE: DIRECT OUTPUT gauge. This procedure should be followed for each speak- er cable connected to the DIRECT [...]

dance may be calculated by the formula: 1 1 1 1 -=- f-+- . . . . etc. ZT ZI 22 Z, where ZT is the total impedance, Z, is the impedance of the first speaker, Z, is the impedance of the second speaker, and so forth, with a total number of fractional terms equal to the total number of speakers in the group. Before at- tempting to add the individual fr[...]

Meter Reading Output Power 100% 1 X 86.7% 3/4X 70.7% 1 /2X 50 % 1 /4X 33.3% 1/10X 10% 1/1oox In most applications, the VOLUME Control (2) setting of the Amplifier is determined by the sound level require- ments of the area being served. Initial adjustments are made in the audio console feeding the Amplifier to set the average program output level t[...]

duce approximately 28.3 volts at the DIRECT OUTPUT terminals (8,9), or 70 volts at the 70V OUTPUT terminals (11) when the 70-volt input line is supplying 70 volts. FIGURE 10. 70-VOLT SYSTEM ATTENUATOR BRIDGING CONNECTIONS If greater power or optimum system reliability becomes extremely important, two Amplifiers may be connected in series (never in [...]

SR105 Power Amplifier SERVICE INSTRUCTIONS AMPLIFIER SERVICE (See Guarantee) The SR105 Power Amplifier uses components of the high- est quality, operating well within their respective ratings to assure long life. WARNING Voltages in this equipment are hazardous to life. Make all input and output connections with ac power disconnected. Refer servici[...]

R39 R40 Dl2 R36 T2 C14 C15 R3 1 Q8 R35 Q7 R43 PL2 MI PL3 (XPL2) (XPL3) Y SRIOSA MODEL ONLY FIGURE 13. SR105 POWER AMPLIFIER TOP VIEW, COVER REMOVED (SRlOSA MODEL SHOWN) adjustment screw below the meter face until the needle is Circuit Board. (The SR105B Amplifier contains only a Main properly positioned. With no load on the Amplifier (speaker Circu[...]

Main Circuit Board SMALL SIGNAL AND PREDRIVER TRANSISTORS Transistors Q1 through Q6, Q13, Q14, and Q201 through Q203 are mounted on printed circuit boards. When re- placing these transistors it is imperative that proper lead configuration be followed. A minimum of soldering heat should be used to avoid damage to the transistor or printed circuit bo[...]

OUTPUT TRANSISTORS Output transistors Q9 through Q12 (Figure 13, Page 13) are located on the black, finned heat sinks. The replace- ment procedure is the same as that used for driver tran- sistors Q7 and Q8. NOTE: Output transistors Q9 through Q12 must be matched for current gain. When replacing output transis- tors, be sure to replace with devices[...]

11 TOOLS /I Description SR105B AMPLIFIER PARTS Pliers, Diagonal, or Wire Stripper *'Four machine screws presently securing rear-panel 70-Volt Conversion Cover (53A1319) may be used. CONVERSION MATERIALS I( Pliers, Long-nose Qty. 2 2 4 4 - - - required. Description Transformer, 70V Output (T3) Switch, Slide, DPDT 64) Terminal Strip, 3- Screw-Te[...]

in the space exposed by removal of the cover using four 6-32 x 3h1' Phillips head machine screws. Be sure to orient the screw contacts on the terminal strip in the same man- ner as the existing DIRECT OUTPUT terminal strip. Mount the slide switch next to the terminal strip in the space pro- vided, using two Phillips round head 4-40 x 3/16"[...]

S 4 OFF JI-J2 e TS2 - - GROMMET x J e 3 d m WHT a FILTER &- + CIRCUIT t BOARD TU 1 YEL / BLK H& RED a J MAIN CIRCUIT BOARD R4 1 VOLUME FIGURE 17. 70-VOLT CONVERSION: INTERNAL WIRING[...]

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REPLACEMENT PARTS FOR SR105 POWER AMPLIFIER 04, D5 I - I - 1 86A415 1 Diode,Silicon, Computer, 75V - Reference Designation Q8 Q9-Q12 R35-R40 R41 R43, R44 R45, R46 S 1 52, S3 S4 TI T2 T3 TB1 TB2 W1 W2 XF1 XPLl XPL2 D8, D9 I RKCl9 1 4 1 86A405 1 Diode, Germanium.30V MAIN CIRCUIT BOARD ASSEMBLY Replacement Kit. NO.* - - - - - - - RKC37 - - - - - - - -[...]

REPLACEMENT PARTS FOR SR105 POWER AMPLIFIER Reference Designation I RKC9 1 4 1 86A349 / Transistor. Silicon. NPN Replacement Kit Consists Of: Kit. No.* Part No. I Descri~tion - - 86A355 Transistor, Silicon, NPN 1 - 1 - / 86A354 1 Transistor, Silicon, Power, PNP Commercial Alternate Motorola 2N5088; TI 2N3711 Motorola MPS-A06 Motorola 2N5680 46A042 [...]

FIGURE 18. MAIN CIRCUIT BOARD PARTS LOCATION DIAGRAM 2038-21525-2 FIGURE 19. FILTER CIRCUIT BOARD PARTS LOCATION DIAGRAM[...]

SR105 Power Amplifier NOTES TO CIRCUIT DIAGRAM GENERAL Shure part numbers are not shown in the Parts List accompanying the Circuit Diagram (Figure 21, Page 25) if parts are readily available through local electronics parts suppliers. In these instances, the Circuit Diagram shows only the reference designation and value of the standard parts. All ca[...]

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LINE LEVEL INPUTS 120 VAC 50160 H r NOTE I: DIFFERENCES BETWEEN SRIOSA AND SR105B: "STRAIGHT- THROUGH" WIRING SHOWS SRlOSB CIRCUITS; SRIOSA CIRCUITS INCLUDE ASSEMBLY A2, SWITCH S4, TRANSFORMER T3, AND TERMINAL STRIP TS2. SRIOSB REFERENCE NO. DESCRIPTION -- R I, R9 WERE 12kb C13 ADDED C17, CIB ADDED FIGURE 21. SR105 POWER AMPLIFIER CIRCUIT[...]

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SR105 Power Amplifier CONDENSED OPERATING INSTRUCTIONS DIRECT SPEAKER OUTPUT (MODELS SRlOSA and SRlOSBI CONSTANT VOLTAGE 70-VOLT SPEAKER OUTPUT (MODEL SRlOSA ONLY) I. 'with line cord unplugged, install Amplifier in rack or l. Amplifier and connect auxiliary equipment as carrying case, allowing adequate ventilation. 2. Connect speakers to DIREC[...]

The Amplifier shall have built-in circuitry to protect the Amplifier from open circuit, short circuit, or mismatched output loads, by using current-limiting, voltage-limiting, temperature-sensing diodes, and thermal-sensing switches. The automatic thermal-sensing switches and temper- ature-sensing diodes shall be mounted on the output tran- sistor [...]