Pro Intercom BP2 User manual

BP2 & BP2B
2-Circuit Portable
Headset Stations
(Beltpacks)
The BP2 and BP2B are best understood if thought of as two separate ‘belt packs’ in one enclosure. Each has its own com-
plete set of controls and its own rear panel XLR for connection to its own circuit.
The BP2 mixes the two audio inputs from the two circuits to which it is connected and may be used with either a sin-
gle-muff or a dual-muff headset. The headset connector is 4-pin.
The BP2B (binaural) maintains the separation of the two audio inputs from the two circuits to which it is connected and
feeds each signal to one side of a dual-muff headset. The headset connector is 5-pin.
Note: On both the BP2 and the BP2B,circuit ‘A’ must be connected to a powered circuit in order for circuit ‘B’ to
operate. Circuit ‘A’ may be used alone. Circuit ‘B’ may not.
1. Plug a headset into the XLR socket on the rear panel. Headset wiring standards are shown on the next page. In Pro In-
tercom systems, the phase of the earphone(s) is the reverse of that sometimes used. This was done to reduce the effect
that the headset connector and wiring has on the headset station bridging impedance and ‘sidetone’ adjustment stability.
(See #8) Either standard of headset wiring will work with Pro Intercom headset stations.
2. Plug a standard microphone cable from each of two circuits on your master station or power supply into each of the
3-pin sockets on the rear panel.
Note: BP2’s and BP2B’s have two 3-pin circuit connectors and cannot be looped-through. To loop-through a
Y-cable must be used.
3. Press the mic. buttons and partly turn up the ‘listen level’ controls on your unit and others on the same circuit(s).
4. You should now be able to communicate with any of these other stations.
5. The thumb operated ‘listen-level’ controls regulate the loudness of your headset earspeaker(s). It has NO effect
on the microphone level or on the level others hear.
6. The microphone amplifier gain is factory adjusted to suit most dynamic or electret headset microphones. It contains a
limiter/compressor which compensates for differences in microphone output and voice levels.
7. The flash (signal) push buttons flash a light in all outstations connected to the same circuit. It is used to attract attention
in the event that a user has removed his/her headset.
8. The screwdriver-adjust preset controls, accessible through the front panel, control the level of your own voice heard in
your own headset. This adjustment is called ‘sidetone’. Sidetone is factory set at a level suitable to the majority of us-
ers. It can be altered for personal preference, or for deep cancellation allowing the headset to be removed and used to
monitor.
Note:Sidetone controls have a null-point near the 12 o’clock position where sidetone is most deeply canceled. Rotating
the control either side of the 12 o’clock position will increase sidetone levels.
(Continued on next page)
Operating Instructions & Connections
Pro Intercom LLC
PO Box 7035 Algonquin Illinois 60102-7035
Phone: [phone] Orders and Tech support: [phone] Fax: [phone]
[email protected] Skype: intercom4pros
Printed in USA Rev.3_01.13

Now you can use headsets with electret microphones!
By convention, in order to avoid any confusion with low impedance microphone jacks, the fe-
male jack on intercom equipment is considered the input. Reversing this order will not effect
performance, but does make it more probable that a reversal of pins 2 and 3 will occur. This is
the single most common cause of failure in both beltpacks and in complete intercom sys-
tems. The reversal will apply 24VDC to the communications conductor which will, at a mini-
mum, cause the signal light system to become erratic and eventually fail, resulting in internal
damage to the beltpack(s).
Rear (Back) Panel Connections
Circuit A
Circuit B BP2
BP2B
4-Pin Headset Pin-outs
1. Microphone shield
2. Microphone +
3. Earphone common
4. Earphone +
5-Pin Headset Pin-outs
1. Microphone shield
2. Microphone +
3. Earphone common
4. Earphone Right +
5. Earphone Left +
The BP2 & BP2B do not provide for looping onwards to another station. To accomplish this requires a YC2
Y-cable. These are available from Pro Intercom or are easily made up as shown below.