Baldwin Boxall BVMX Operating instructions

Baldwin Boxall
Brand
Baldwin Boxall
Model
BVMX
Type
Operating instructions
Baldwin Boxall Communications Ltd.
Wealden Industrial Estate, Farningham Road
Crowborough, East Sussex, TN6 2JR
Telephone: 01892 664422 Fax: 01892 663146
Website: www.baldwinboxall.co.uk
Email: mail@baldwinboxall.co.uk
IBVMX
Issue 4 12/01/1999
BVMX Mixer and
BVMS1 Mixer Output Module
Operating Instructions
- 2 - Issue 4
BVMX MIXER
The BVMX will accept up to a maximum of 11 single width input or output modules, for example 10
input modules and 1 output module. A 6 way dual in line switch enables the signal buses to be
isolated thus providing two independent output channels between module 5 and 6. Using this switch it
is easy to realise a two output channel mixer with input modules occupying positions 1-4 and the
output module in position 5, input modules in position 6-10 and the output module in position 11. It is
possible to obtain further output channels by carefully drilling out the appropriate through hole
connection adjacent to the pin of each input edge connector.
Two separate two pole changeover relays provide switching of external AC or DC signals up to 100V
at 5 Amps maximum, for busy indicators, volume restoration relays etc. Also available on each 8 way
connector is +24V and 0V at 1 Amp maximum to power external circuits. If "Rest" is selected "Off"
on the DIL switch relay RLY1 will only operate from module sockets 1-5 and relay RLY2 will operate
from 6-11. When the "Rest" is selected "On", both relays will operate from all module sockets.
Please refer to data on IMP modules.
The BVMX obtains 24V DC power from a PSU/Charger BVPS and maybe powered by two separate
sources to ensure operation. The mixer may also be used as a stand alone mixer and interfaced with
other equipment. To power it use the BVMXPSU power supply. These supplies are presented by a
two way crimp terminated locking connectors. Front panel LED indicators illuminate when the
associated supply is present.
Depending on the input module fitted and the selection of its internal switches the audio output signal
may be routed to one of two bus lines. The output module type number BVMS1 has a virtual earth
mixer stage connected to each of these audio signal paths. It is possible by switch selection to achieve
priority on audio highway PA Pin No 5 Channel 1 over audio highway Channel 2 on Pin No 4.
Channel 1 the priority channel incorporates a switchable low pass filter at 12KHz and the output may
be routed direct to the output or via the bass and treble control. Channel 2 incorporates a high pass
filter switchable at 300Hz and its output is routed via the tone controls to the output. Each channel has
its own independent master gain control which are presented on the front panel. The access terminal
of the rear panel connector that the output stage occupies may be switched to either:
1. A pre-fade output from channel two for tape recording,
2. DC controlled access channel one over channel two, connect to 0V to enable channel 1,
3. An unbalanced audio output when this module is fitted in the standard Adept amplifier main
frame,
4. DC controlled remote volume when the remote volume control option is fitted.
Three four way connectors enable options to be inserted in the following positions:
A. Channel 1 before the master gain control J2.
B. Channel 2 before the master gain control J3.
C. After the bass and treble control stage J4.
Another four way connector J1 is provided which enables the use of the virtual earth mixing stages as
buffers to feed additional output stages, for example a system that requires a number of ambient noise
sensors feeding independent areas. Switches associated with the input of the virtual earth amplifier
provide the correct attenuation when used in this mode.
Each output module has 4 LEDs to indicate the output level, 5% 50% 100% and 120% the nominal
output level i.e. 100% is 0.775V but signals to a maximum of 2.5V is possible.
- 3 - Issue 4
SW2 SWITCH FUNCTIONS
1. PRI - set to 'ON' for priority.
Channel 1 when accessed will override Channel 2.
Note: to access Channel 1 select ACC switch 'ON' and connect access terminal to 0V.
Set 'OFF' to mix both channels together.
2. LP - set 'on' to by pass the 12KHz low pass filter on Channel 1.
3. * OUT - set to 'ON' to provide an unbalanced output from the access terminal or output to feed the
power amplifier when fitted in an Adept mixer amplifier.
Note: set (4) ACC and (5) PF to 'OFF'.
4. * ACC - set to 'ON' for priority access. Used in conjunction with PRI above.
Note:- set (3) OUT and (5) PF to 'OFF'.
5. * PF - set to 'ON' to provide a prefade output from Channel 2 for tape recording etc.
Note: set (3) OUT and (4) ACC to 'OFF'.
6. TC - set to 'ON' to route Channel 1 direct to the output, not via the bass and treble controls. Note: set
(8) TC to 'OFF'.
7. HP - set to'ON' to bypass the 300Hz high pass filter on Channel 2.
8. TC - set to 'ON' to route Channel 1 via the Bass and Treble controls.
Note: set (6) TC to 'OFF'.
* ONLY SET ONE SWITCH TO THE 'ON' POSITION
SW1 SWITCH FUNCTIONS
1. Set to 'ON' for virtual earth (summing) input, normal mixing mode on Channel 2.
Set to 'OFF' for high impedance input, when used in the buffer mode.
2. Set to 'ON' for virtual earth (summing) input, normal mixing mode on Channel 1.
Set to 'OFF' for high impedance input, when used in the buffer mode.
ON
12345678
4
1
LP
OUT
ACC
PF
TC
HP
TC
14
14
ON
12
Sw 1
Sw 2
J4
J1
J3
J2
SIGNAL PROCESSING OPTIONS
Channel 1 before master control
Channel 2 before master control
After Bass & Treble Controls
DC Volume Control
Connector BVMS2
Bass Treble
Sw 2 Switch
Functions.
Channel 1 OUT
Channel 2 OUT
See text Input Stage in/out
OFF = Buffer
Input Mode ON = Mixing
Channel 1 Master
Channel 2 Master
Pull Knob to Remove
4
1
PRI
Channel 2 IN
Channel 1 IN
Fig 1: BVMS1
Connector and
Selector Locations
- 4 - Issue 4
The BVML Module
The BVML module allows external access to the internal Priority, Busy and Chime bus lines within a
BVMX mixer mainframe. This enables equal (first come first serve) priority to be achieved when
multiple mixers are used.
As the internal bus employs static sensitive logic devices the BVML incorporates the essential
protection components.
A BVMS1 mixer module is required in each of the BVMX mainframes to obtain the audio output. We
do not recommend or provide the facility to parallel the low level virtual earth mixing, audio bus lines
from one BVMX to another, due to hum, noise and instability problems that could occur. Mixing of
the BVMS1 outputs is easily achieved by connecting them in series.
The BVML occupies one module space and presents the internal bus on the 4-way BVMX connector
shown below.
BVMX Rear Panel Connector BVMX Internal Bus
A Busy
B Chime
0V 0V
Access Priority in/out
Figure 5 illustrates a system using three BVMX linked via BVML providing 25 microphone inputs,
one having total priority, 24 with first come first serve priority and an IMP33 pre-announcement
chime.
Edge Connector
180k
180k
Gate Option
J2
180k
180k
Gate
6
5
4
Input
mixing
bus
CHANNEL 1
+20V
R1
R2
LOGIC
Priority 1
Sw 2
Input Stage in/out
J1
Sw 1* 2
Sw 1* 1
Low
Pass
Sw 22Master
TC
Sw 2
TC
8
6
Option
CHANNEL 2
J3
Pass
Sw 2
High 7
0V
Master Prefade
Access
Out
Sw 2
DC VC
0V
0V
J4
Option
Bass &
Treble
Controls
5
4
3
BVMS2
Output
Level
Indicator
120%
100%
50%
5%
BVMX Connector
Access Ground BA
in/out
7321
+20V
PA
MS
* Select buffer mode
Fig 2: BVMS1 Block Diagram
- 5 - Issue 4
IN A
IN B
0V
MS
PA
20V+VE
ACCESS
CHIME
BUSY
REST
PRI. IN
PRI. OUT
EARTH
2
3
1
4
5
6
7
8
9
1 0
1 1
1 2
2
3
1
4
5
6
7
8
9
1 0
1 1
1 2
2
3
1
4
5
6
7
8
9
1 0
1 1
1 2
2
3
1
4
5
6
7
8
9
1 0
1 1
1 2
2
3
1
4
5
6
7
8
9
1 0
1 1
1 2
2
3
1
4
5
6
7
8
9
1 0
1 1
1 2
2
3
1
4
5
6
7
8
9
1 0
1 1
1 2
2
3
1
4
5
6
7
8
9
1 0
1 1
1 2
2
3
1
4
5
6
7
8
9
1 0
1 1
1 2
SELECT 'ON' TO
JOIN 1-5 TO 6 -1 1
Drill to break bus line
between 4 and 5
MS
PA
CHIME
BUSY
REST
PRI
BALDWIN BOXALL COMMUNICATIONS LTD
INPUT B
DC SUPPLYDC SUPPLY
INPUT A
RLY 1RLY 2
CHANNELS 1-5CHANNELS 6-11
CONN
12
+VB
+VA
0V
0VCONN
13
CONN
14
ON
123456
PC 1116
MODULE CONNECTORS
INPUT/OUTPUT CONNECTORS
REG 2-7
+20V INPUT/OUTPUT
MODULESREG 1
+24V OUT
C
Supply LEDs 1 & 2
mounted on PC 1122
4321
1 1
1234567891 01 1
1234567891 0
11109876543
SUPPLY INPUTSUPPLY INPUT
AB
0V +24V
BUSY/VOLUME RESTORATION OUTPUT
CONTACTS 5A MAX
CHANNELS 6-11+24V OUTPUT 1A MAX
CHANNELS 1-5
+24V 0V+24V 0V
AERIAL 1
AERIAL 2
0V GROUND
ACCESS ETCSIGNAL
IN/OUT
A
B
INPUT/OUTPUT
CHANNELS
BALDWIN BOXALL COMMUNICATIONS LTD. ENGLAND TEL 01892 664422
9 way D connector
providing fault output
is fitted
when IMP9, IMP41 etc.
Aerial coax socket
when IMP11 is fitted
Input/output connectors
21
ACCESS ETC
0V GROUNDA
BSIGNAL IN/OUT
Fig 3 (above): BVMX Plan View
Fig 4 (right): BVMX Rear View
- 6 - Issue 4
INPUTS 2-9
SET FOR EQUAL
(FIRST COME FIRST
SERVE) PRIORITY
AND CHIME
AB
SIGNAL
IN/OUT
OV
GROUND
ACCESS
AB
SIGNAL
IN/OUT
OV
GROUND
ACCESS
AB
IN/OUT
OV
GROUND
ACCESS
AB
SIGNAL
IN/OUT
OV
GROUND
ACCESS
12 1011
WILL OVERRIDE
ALL OTHER INPUTS
SIGNAL
1891011
IMPX IMPX BVMLIMPX
SET FOR CASCADE
PRIORITY & CHIME
BVMX
PLAN
VIEW
CHANNELS 1-5 CHANNELS 6-11
BUSY/VOLUME RESTORATION OUTPUT
PRIORITY
0V
CHIME
BUSY
INPUTS 2-9
SET FOR EQUAL
(FIRST COME FIRST
SERVE) PRIORITY
AND CHIME
AB
SIGNAL
IN/OUT
OV
GROUND
ACCESS
AB
SIGNAL
IN/OUT
OV
GROUND
ACCESS
AB
IN/OUT
OV
GROUND
ACCESS
AB
SIGNAL
IN/OUT
OV
GROUND
ACCESS
12 1011
SIGNAL
1891011
IMPX IMPX BVMLBVML
BVMX
PLAN
VIEW
CHANNELS 1-5 CHANNELS 6-11
BUSY/VOLUME RESTORATION OUTPUT
INPUTS 2-9
SET FOR EQUAL
(FIRST COME FIRST
SERVE) PRIORITY
AND CHIME
AB
SIGNAL
IN/OUT
OV
GROUND
ACCESS
AB
SIGNAL
IN/OUT
OV
GROUND
ACCESS
AB
IN/OUT
OV
GROUND
ACCESS
AB
SIGNAL
IN/OUT
OV
GROUND
ACCESS
12 1011
SIGNAL
0dB OUTPUT
1891011
IMPX IMPXBVML IMP33
CHIME
BVMX
PLAN
VIEW
CHANNELS 1-5 CHANNELS 6-11
BUSY/VOLUME RESTORATION OUTPUT
PRIORITY
0V
CHIME
BUSY
PRIORITY
0V
CHIME
BUSY
BVMS1
BVMS1
BVMS1
1
BVMX
BVMX
BVMX
2
3
Fig 5: Connection
details for Three
BVMX Mixers
linked via BVML
Modules,
providing 25
Microphone
Inputs with Chime
  • Page 1 1
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  • Page 3 3
  • Page 4 4
  • Page 5 5
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Baldwin Boxall BVMX Operating instructions

Baldwin Boxall
Brand
Baldwin Boxall
Model
BVMX
Type
Operating instructions
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