Shure AMS880 Schematic

222 HARTREY AVE., AREA CODE 31 21866-2200 CABLE: SHUREMICRO

TWX.

0-231 -0048 TELEX: 72-4381

EVANSTON,

IL, 60204

S.A

DATA SHEET

MODEL AMS880

PONENTS

VIDEO SWITCHER INTERFACE

The Shure Model AMS880 is a Video Switcher Interface which expands the Shure Automatic Microphone System [AMS] for use in video teleconferencing applications. The heart of the

AMS880 is an 8748 microcomputer which actuates the remote-control input of a commercially available video switcher in response to the action of an automatic microphone mixer such as the Shure

AMS4000 or AMS8000. Video cameras covering individual microphones are thereby activated when their microphones are activated, causing the video presentation to smoothly follow the flow of the audio discourse. Three additional options are also available. First, the

vidoo

channel [such as a wide-angle camera] after a

AMS880 can select a particular

predetermined period of audio inactivity. Second, the AMS880 contains an "override" option that suspends automatic action and permits external manual switch selection of a

particular video channel, such as a graphics camera. Third, a "disable" input is available to suspend all automatic action and allow manual camera selection via switches externally connected in parallel to the

AMS880

outputs.

AMS880 is designed for mounting in a standard 19"

The equipment rack, or, using supplied feet, on any horizontal surface. The unit is powered by an external power transformer which is Listed by Underwriters Laboratories,

Inc.

SPECIFICATIONS Inputs

Logic Gate Inputs: 8 plus logic ground Open Circuit Voltage:

Resistance: 1 kilohm

Low

Logic Status:

channel gated on

lnput Protection: To 1 2V

Outputs

[FET

optically

isolated; not connected to input

ground]

Off Resistance: Greater than 300 megohms On Resistance: Less than 200 ohms Switching Time: Less than 1 msec Output Closure: Selected output will pulse closed for

250 msec; may [optionally] provide maintained closure

Power

External power transformer: 1 20 Vac + lo%, 60 Hz, 6W

Temperature Range

Operating: Storage:

-7O to 57OC [20° to 135OFI 8" to 71 OC

-1

[0°

to 1 60°F]

Dimensions

44.5mmHx483mmWx127mmD[1 3hin.x19in.x

in.]

Weight

kilograms [2.5 Ib], including transformer

Supplied Accessories

Adhesive feet for surface mounting; screws and washers for rack mounting;

mating output connector

[25-pin DB25P type with separate solderable contacts, locking screws and back shell with cable clamp]

INSTALLATION AND OPERATION Controls, Indicators and Connectors

The front panel of the AMS880 contains a push-button power-on switch and a green power-on indicator. The

1.2m

ft]

rear panel contains a

multiconductor ribbon input cable which consists of eight channel Gate Out logic inputs and a logic ground. Color coding of the ribbon cable is shown in Table 1

TABLE

Color

Brown

Red Orange Yellow Green

INPUT CABLE CONNECTIONS

Function

Gate 1 Gate 2 Gate

Gate

Color

Purple Gate White Ground

Function

Gate Gate

Gate 5

The rear panel also contains a connector for the external power transformer, and a 25-socket subminiature D-type output connector for connection to the remote-control input of a video

[DB25S type] with locking screw studs

switcher such as the 3M Video Bridging Switcher Model 101. The AMS880 is supplied with a matching 25-pin connector for connection to the video switcher cable.

Pinlsocket connec-

tions for the 25-socket connector are given in Table 2.

TABLE

Output Output Output

N.C.

OUTPUT CONNECTOR TERMINALS

1 1

Output Cornrnol

17 N.C.

Ground Ground

N.C.

22 N.C.

N.C.

The printed circuit board contains two eight-station DIP switches which provide option selection as follows. Factory preset positions are given in boldface type.

27A8044

1982, [El]

Shure Brothers

Inc

TABLE

Switch 6 Station

OPTION SWITCH FUNCTIONS

Function

lnput

T~rne

Delay

Autornat~c

Automat~c

ldle

T~nie

Opt~on

See

Table

Select~on

Overr~de

53-2 Overr~de Channel 53-3 53 53-5 53-6 53

Overr~de Overr~de Overr~de

Overr~de Overr~de

53-8 Overr~de Channel

*Off posltlon

TABLE

marked OPEN, On posltlon 1s not marked

AUTOMATIC IDLE CHANNEL SELECTION

Rotat~on

Rate

Output

Mode Ma~ntaned

Channel

Channel 3 Channel

Channel 5 Channel

Channel

O~sabled

Enabled

Enabled Enabled

2.7

sec

Pulsed Disabled Disabled Disabled Disabled Disabled Disabled Disabled Disabled

152-8pFEJ+s2i4-

Channel

Off Off Off Off

On On On On

Install the

lf any changes from the factory preset optlons are desired, remove the ches

AMS88O as follows.

AMS880 cover and set option swit-

[S2, S3] for the desired function [see tables 3 and

Off Off On On

Off

Off Un On

and explanations below]. Replace the cover.

2. Install the

AMS880 in a standard 19-inch equipment rack [screws and washers are provided] or on a horizontal surface [protective feet are provided].

Fabricate

and the connector. and the

4. Connect the leads of the multiconductor

a connecting cable between the video switcher

AMS880 using the supplied 25-pin DB25P type

Install the cable between the video switcher

AMS880 output jack.

lnput cable of the AMS880 to the Gate Out terminals of the AMS mixer follow~ng the EIA color coding [brown-Channel Channel 2, etc. as shown in Table I]. Connect the AMS880 white input lead [Ground] to the Channel 8 [AMSBOOQ] or Channel 4 [AMS4000] Loglc Ground terminal of the AMS mixer.

5. Connect the external power transformer to AMS880.

6. Connect the power transformer to a 120 Vac, 60 Hz source.

Operation

With all equipment connected, turn the AMS880 on by

depressing the Power

sw~tch. If no funct~on options have been changed from their factory settings [using internal switches

52 and S3], a given camera channel will be

selected after its AMS mixer channel has been on for

Off On Off On

red-

. the

2.5

seconds. This input time delay prevents changing cameras if an AMS such as brief paper the time delay can be decreased from 2.5 to

mlxer channel has been activated by a short sound

rustllng or chair squeaking. Note that

1.9

seconds by

movlng switch 52-1 to the "off" position.

Dur~ng periods of

inactivity,

the last camera channel activated will remain on. It two or more AMS mixer channels are active rotate among those among those channels at a rate of

s~multaneously, camera channel selection w~ll

2.7

seconds per channel. The rotatlon action can be disabled by movlng switch S2-7 to the "on" [non-OPEN] posit~on.

Options

Automatic ldle Opt~on

Internal switches S2-2 through S2-6 are assigned to the

automatic

Idle channel function. When an automatlc Idle channel has been selected, cessation of activlty by the AMS mixer for more than 6.2 seconds will cause the autornatlc idle channel to be activated. This allows switching to a angle or a graphics camera when no one

talk~ng. Normal

wide-

action is restored when any input is active for the selected Input time delay of 2.5 or 1.9 seconds.

Switch

52-2 turns the automatic idle function on or off.

Switch S2-3 chooses the automatic idle time delay of 6.2 or

8.8 seconds. Switches S2-4, S2-5 and S2-6 select,

through a binary logic code system [see Table

41,

the

number of the channel selected for the automatic idle opera-

tion.

Overr~de Option

Any or all input channels can he selected to automatlc channel selected override

selectron funct~on

Inputs

will

usually be actrvated by a manual

the AMS mixer The

overrlde the

sw~tch closure to ground, rather than an AMS mixer gate output When S3-1 through

overrlde lnput actlvated wlll take precedence over those

any channels normally more than one Input actlvated

actlvated by the AMS mlxer operation If

overr~de option channel 1s enabled, the f~rst

will

turn on Heleasrng all overrlde Input

53-8 are enabled [turned on].

switch closures to ground w~ll restore automatic AMS m~xer-controlled actlon

Disable Option

An external switch closure from Output Connector pin 23

to pin 25 [Ground] will suspend all

autornatic action, allowing

any parallel-connected [external] switch closures between

[p~n

1 1

]

Output Connector Common [pins 1 through

81 to control the vrdeo switcher's action.

and Output Channels

Releasing the Disable switch closure will immediately restore automatic action.

GUARANTEE

This Shure product

from electrical and mechanical defects for a

guaranteed In normal use to be free

per~od of one year from date of purchase. Please retain proof of purchase date. This guarantee includes all parts and labor. This guarantee is in lieu of any and all other guarantees or warranties, express or implied, and there shall be no recovery for any

conseq~jentlal or incidental damages.

Carefully repack the

unlt, insure ~t, and return

prepa~d

to: Shure Brothers Incorporated

Attention: Service Department 222 Hartrey Avenue Evanston, Illinois 60204

If outside the United States, return the unit to your dealer or Authorized Shure Service Center for repair. The unit will be returned to you prepaid.

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