M411 — Transcription Preamplifier

The M411 is a two-channel_ ac operated, equalized preamplifier designed to provide high quality disc reproduction for broadcast and sound recording applications The unit accommodates two independent plug-in, equalized amplifier cards for stereo or two separate monaural channel operation: FEATURES: Compact design , self-powered utilizing 1C components State-of-the-art operational amplifier circuits and bi-polar power supply provide sufficient gain to produce OdBm balanced output level with less than 2.5 micro-volts input noise_ Dual operational amplifiers deliver + 22dBm max to a balanced output load_ A sum signal is developed to produce a balanced mono auxiliary output: Stereo , Mono or Two separate monaural channel operation Line level output (OdBm from SmV cartridge output) An integral active filter maintains precise RIAA frequency reponse at 30Hz but rapidly reduces gain below 20Hz to eliminate the effects of turntable rumble.

A remotely controlled FET switch introduces a high frequency scratch filter to render the reproduction of noisy discs less objectionable. Precise RIAA/NAB equalization The compact M411 mounts directly on the turntable surface or cabinet, installed through a prescribed cut-out. removable front panel escutcheon exposes the plug-in electronics containing all pre-set screwdriver adjust controls: Thus, performance characteristics may be conveniently varied at the operating surface.

Four trim controls are incorporated on each PC card to permit independent adjustment of gain, cartridge loading and high and Iow frequency response: Permanent rumble filter 25dB at 1OHz. Selectable FET HF filter Individual cartridge loading , gain, high and low frequency trim controls for each channel: 8 {

The M4I TwO-channel; dc operated equalized preamplifier designed Provide high qualily disc reproduction foi broadcasi arid sound recording applicatiotts: The Unit accommodales (wn independent plug equalzed amplitier cards sterec UWO spjraic monaui channc opialiom FEATURES: Comnpact sesigu, Sil-powered utilizing IC components State-ot-the-art operatianal amplifier circuits and bi-polar power supply provide sufticient gain produce OaBm palanced output level with less Ihar 25 mnicro volts inpui 00is oputatioral arplifiers deliver 22dB II md ` balanced outpur load.

shna develored nroduce ualanced (MJIIO uuxilmy OulpuL Steren, Mcto Or Two sxparate Inonaur channol opcration Line level output (Odkm trom SmnV carir idge OUIEUt) An Wtecral uctive f Iter maintains precis AIAA frequency Fedonse 3UH? Dul rapiOIY reduc; gain below ZOHZ t0 eliminalc effects turntablo rurble {emote controlled FET switch introduces high trecueticy Scratcl filtct render the #cproduction of noisy diSL; less objectionable- Pracise RIAA NAB equalization The compact M41 mounts directly on the urntable surtece Cr Cabinet; anstalled through prescribed cut-out; rernovable tront [und esru cnenn expuss the' plug-Iri electoniss comhitng 0ic *- screwdrivar adjust controls Ts purforrarce ciadesusmay convenicnty "aricd the operating JufJCO FOUI controls aro incorporaled each PC card permt incependent adjustment gain; cartridge' ldading and high and low Frequency raspunse Permanerl futble filtes 2odB TOHz Selectable FET HF filter Irdividual cartridge |Qacing , gain; hiyh and Iow "requency Irin Lonirols T0r cach channel

GAIN Adjustable. Sm V rms input level produces OdBm output level: (Equivalent to 44dB with 600 ohm terminated source)_ FREQUENCY RESPONSE RIAAINAB equalization characteristic within + IdB from 30Hz to 15kHz . Integral rumble filter produces 25dB at 1OHz Scratch filter , selectable , greater than 6dB down at 6kHz _ and _2OdB at 1OkHz NOISE Less than 2.5 micro-volts input noise (measured 1OHz to 100kHz bandwidth and with 600 ohm terminated input) Equivalent to 1OdBm input noise.

TOTAL HARMONIC DISTORTION Less than 0.5% from 3OHz to 15kHz (measured at + 2OdBm output level) INPUT IMPEDANCE Adjustable 20k ohm to 60k ohm, unbalanced INPUT LEVEL SmV nominal, 0.25V max_ ACCESSORIES: LOAD IMPEDANCE 150 ohms or higher , balanced OUTPUT IMPEDANCE 50 ohms, balanced OUTPUT LEVEL OdBm nominal, 22dBm max SUM OUTPUT L+R OdBm nominal PHASING The centre pin (hot signal) of the input phono connector and the low terminal number of the output pair are in phase _ POWER REQUIREMENTS 115Vac, 6OHz , SVA AMBIENT TEMPERATURE 08 to 60'c DIMENSIONS 2.5w 10H x 7.50 (Depth below surface) inches WEIGHT 4.5 Ibs net Order- or M411 Mono Transcription Preamplifier equipped with ONE plug-in amplifier card M411S Stereo Transcription Preamplifier equipped with TWO plug-in amplifier cards.

WARD-BECK SYSTEMS LTD; WARD-BECK SYSTEMS INC- 841 Progress Ave,Scarborough,Ont M1H 2x4 290 Larkin St;, Buffalo, New York 14210 Telephone: (416) 438-6550 Telex: 06-23469 WBS

GAIN Adjustable. Sm V rms input level produces OdBm output level: (Equivalent to 44dB with 600 ohm terminated source) FREQUENCY RESPONSE RIAAINAB equalization characteristic within + IdB from 30Hz to 15kHz . Integral rumble filter produces 25dB at 1OHz Scratch filter , selectable , greater than 6dB down at 6kHz_ and _2OdB at 1OkHz NOISE Less than 2.5 micro-volts input noise (measured 1OHZ to 100kHz bandwidth and with 600 ohm terminated input) Equivalent to 1OdBm input noise_ TOTAL HARMONIC DISTORTION Less than 0.5% from 30Hz to 15kHz (measured at + 2OdBm output level) INPUT IMPEDANCE Adjustable 20k ohm to 60k ohm, unbalanced INPUT LEVEL SmV nominal, 0.25V max_ ACCESSORIES: LOAD IMPEDANCE 150 ohms or higher , balanced OUTPUT IMPEDANCE 150 ohms, balanced OUTPUT LEVEL OdBm nominal, 22dBm max SUM OUTPUT L+R OdBm nominal PHASING The centre pin (hot signal) of the input phono connector and the low terminal number of the output pair are in phase_ POWER REQUIREMENTS 115Vac, 6OHz , SVA AMBIENT TEMPERATURE 08 to 608c DIMENSIONS 2.5w 10H 7.50 (Depth below surface) inches WEIGHT 4.5 Ibs net Order - or M411 Mono Transcription Preamplifier equipped with ONE plug-in amplifier card M411S Stereo Transcription Preamplifier equipped with TWO plug-in amplifier cards.

WARD-BECK SYSTEMS LTD; WARD-BECK SYSTEMS INC - 841 Progress Ave,Scarborough,Ont M1H 2x4 290 Larkin St;, Buffalo; New York 14210 Telephone: (416) 438-6550 Telex: 06-23469 WBS

GAIN Adjustable bm V rms input level produces OaBm output Jevei (Equivalent 44dB with 6C ohm tertninaled sourcel . FREQUENCY RESPONSE RIAAINAE equalizalioni charactaristic within IdB tom 3HZ TEKHz. Integral rumble filter produces 2548 1OHZ, Scratch filter , selectable, grealer Aan GdB down at 6*Hz, "ZOdB JOkHz NOISE Less than 2,5 mnico-volls iriput noise: (reasured IOHz t0 1OOkHe bandividth and with GUU ohin Terminaled IFMAtA Equivalent TICBm iput nois TOTAL HARMONIC DISTORTION Less Ihan 0.53 from 30Hz i0 ISkHz (measured a1 ZUdBm output levcll_ INPUT IMPEDANCE Adjustable 20k ohmi to 60k ofm, urbalanccd INPUT LEVEL 5nV riomninal, '25V mnax; ACCESSORIES: LOAD IMPEDANCE 150 ohins €r nigner , balanced OUTPUT IMPEDANCE 150 ohms; Dalanced OUTPUT LEVEL OdBm nominal 22dBm max; SUM OUTPUT +R OdBm nominal PHASING Ttic centre pin (tt = Sinni Inut Jhon ConNuLd Tna termind number of the cutput pair are phlas POWER RFQUIREMENTS I5Vac, GOFI2.

SVA AMBIENT TEMPERATURE 0"t0 60"c DIMENSIONS 251 IOH SD (Deptn bxlow surdacel inches WEIGHT Ibs net Order: M411 Mono Transcription Prewplifier equipped with ONE plug-in amplitiar card M4l1S Stereo ranscription Preamolifier equipped with FWO plug in amplifier cards WARD-BECK SYSTEMS LTD; WARD BECK SYSTEMS INC_ B41Prorrula OOl TETLON N P*e 2C0 ICEN r | Autlo Nuvd YCrk "14210 TelejJn= [4151 438-6E50 Te ^ 08-234C9 WBS

SYMBOL DESCRIPT I ON MFG PART NUMBER mFd 35V 015 mFd 250V 4.7 mFd 25V mFd 35V 022 mFd 100v Keme t Phi1 ips Kemet Kemet Aselco T390B 105M035AS 344ABA15K T390C475MO25AS T390B105M035AS 223M 8 88 C9 C10 C11 C12 C13 C14 C15 C16 cib 18 C19 C20 3900 PFd 100v 068 mFd 100v 022 mFd 250V 3300 pFd 100V Aselco Philips Philips Aselco 392M 344CH A68K 344AB A22K 332M 4.7 mFd 25V 022 mFd 100v Kemet Aselco T390c475M0254S 223M 4700 pFd 100V 4700 pFd 100v Aselco Aselco 472M 472M mFd 35V 2200 pFd 100v 2200 pFd 100v 4 7 mFd 25V 100 mFd 16v Kemet Aselco Aselco Kemet Siemens T390B105M035AS 222M 222M T390C475M025AS B4 1281- C4107-$ C2 C22 C23 C24 C25 100 mFd 16V 47 mFd 40V 022 mFd 100v 10 pFd 100v 220 mFd 25V S iemens Siemens Aselco Philips Siemens B4 1281-C4107-S B4 1283-C7476 -T 223M 2222 638 10109 B4 1283-B5227-T C26 C27 C28 C29 C30 220 mFd 25V 022 mFd 100v 10 pFd 100v 220 mFd 10V 220 mFd 10V Siemens Aselco Philips Keme t Kemet B4 1283-B5227- T 223M 2222 638 10109 T390F227M010AS T390F227MO1OAS C3 C32 C33 C34 C35 220 mFd 10V 220 mFd 10V 01 mFd 250V 470 pFd 100v 2 .2 mFd 25V (Sot) Kemet Kemet Phi lips Philips Kemet T390F227M0 OAS T390F227M0 OAs 344AB A10k 2222 630 03471 T390B225M025AS C36 C37 68 pFd 100v 68 PFd 100v Philips Phi ]ips 2222 638.70689 2222 638 70689

SYMBOL DESCR[PTI ON MFG PART NUMBER C101 C102 500 mFd 35V 500 mFd 35V S iemens Siemens B4 1010-C7507-$ B4 1010-C7507-$ CRI CR2 CR3 CRY CRS Diode Diode Diode Diode Diode Fairchild Fairchild Fairchild Fairchild Fairchi Id N4 148 148 iN 148 1N4 148 1N4148 CR6 CRZ Diode Diode Fairchild Fairchi ld 1N4148 1N4754 CR101 CR102 CR103 CR104 Diode Assemb ly Diode Assemb ly Diode Assemb Iy Diode AssembIy Motorola Motorola Motorola Motorola MDA 942-4 MDA 942-4 MDA 942-4 MDA 942-4 FET FET NPN Transistor NPN Transistor PNP Transistor Fairchild Fairchild Motorola Motorola Motorola 2N4360 2N4360 2N4401 2N2102 2N4037 8 PNP Transistor 86 NPN Transistor 22 Integrated Circuit Integrated Circuit 15K A]1 Resi stors 820 1/4W 5% unless 3 10 otherw se 220K speci fied 15K R6 5K Pot RB 2 .2K 5K Pot R9 43K R1O 470K Motorola Motorola 2N4037 2N2102 Fairchild Fairchild 739 739 Philips Piher PT 1OH-5K Piher PT 1OH-5K RI1 R12 R13 R14 R15 10 100K 2.7K 620 100K

SYMBOL DESCRIPTI ON MFG PART NUMBER R56 R57 1K 1K T1o1 Power Transformer WB S 80-11 TB Terminal Block Cinch-Jones 10- 140-Y Fuse Post Fuse Post Littelfuse 342004 F101 0.5 Amp SB 3AG Type Littelfuse 313.500 XQ Heat Sink (4) Birtcher 3AL680-ZR 00-6007-015- 940-002 8 1B JI & J2 15 Pin Connector Elco Jacks Doub le Phono Jack Cinch-Jones Phono Plugs Printed Circuit Board Cinch-Jones 13A PCB WBS M158 PCB Gui de Elco 63-9016-1201-01 Handles Extractor Handles Birtcher 60-1- 2 Cord Ac Cord Be I den E-24963