Corridor - Intercom Interface for Blackmagic Designs© to Clearcom© and RTS©
Intercom Interface for Blackmagic Designs© to Clearcom© and RTS©
Corridor has two channels of intercom interface.
Channel A is a standard 2 wire to 4 wire intercom interface.
Channel B is a 2 wire Clearcom© and RTS© compatible with Blackmagic Designs Studio Converter and Talkback Converter.
Front Panel Controls
Improper sidetone could cause feedback between input and output.
Sidetone Adjustment Procedure:
- Set Link (5) switch to OFF.
Turn the Input Level Reduction Switch (8) to 0dB.
Press Test Tone (7) button, a constant beep sound can be heard from the Sidetone (6) Monitor.
- Adjust Output Level (9) control knob to make the beep level heard properly.
- Turn the Main Sidetone Adjustment M (1) knob by clockwise and anti-clockwise direction slowly.
- Find minimum listening level.
Turn the Auxiliary Sidetone Adjustment A (1) Find the minimum listening level.
Repeat this procedure 1) to 7) for the other channel.
Output Level Output Level Reduction Switch (8)
This switch has 0dB, -20dB and -40dB three levels. It reduces the signal level which is sent to the pins 3 and 4 of the 4-wire connector (13) on the rear panel of Channel A or the BNC OUT of Channel B.
Output Level Adjustment (9)
This output level adjustment provides a strong average green light on the Output Level Indicator (10). This occurrence indicates a 0dB line level on 600ohm line. Red light indicates exceeded output level. Occasional transitions to a red light are acceptable.
Output Level Indicator (10)
A green light indicates the output level is normal.
Red light indicates the output level is high.
Input Level Input Level Reduction Switch (2)
This switch has 0dB and -20dB two levels to match the signal level which is sent from pins 1 and 2 of the 4-wire connector (13) at the rear panel of Channel A or the BNC IN of the rear panel of Channel B.
Input Level Adjustment (6)
Adjust the Input channel gain to fit different input signal level. This knob provides a strong average green light on the Input Level Indicator (4). Meanwhile, the level on pin 3 of the 2-wire connector is 0dB. Red light indicates exceeded input level. Occasional transitions to a red light are acceptable.
Input Level Indicator (4)
The green light indicates the input level is normal.
Red light indicates the input level is high.
Channel A and Channel B are separate from each other when this switch is set to the Off position. When this switch is set to ON position, Channel A and Channel B are connected.
4-wire In/Out Connector (8)
Input: Pin1 --- Audio+
Pin2 --- Audio- (Common)
Output: Pin3 --- Audio- (Common)
Pin4 --- Audio+
External signal to the Corridor can be balanced or unbalanced. An unbalanced signal is more susceptible to noise. Balanced signals have better noise canceling.
Intercom Line Connector (9)
3-pin XLR female
Pin 1 --- Common (Shield)
Pin 2 --- Power (15~30 VDC)
Pin 3 --- Audio
The Corridor comes in a standard 19 inch 1U case which can be mounted in a rack or placed on a desktop. It can be powered by either the A or B channel from the intercom base station using standard mic cable.
Two XLR-3 connectors for channel A and B are used to connect 2-wire equipment. Pin connector is used to connect 4-wire input and output equipment. BNC connectors are available for AES/EBU equipment like Blackmagic Designs Talkback Converters.
Problem: Acoustical feedback
Cause 1: Input or output signal level is too high
Solution 1: Adjust the signal level
Cause 2: Sidetone of this station or any remote station is not adjusted correctly
Solution 2: Adjust side tone refer to the procedure in the Front Panel section of this manual.
Cause 3: No termination in the system.
Solution 3: Check the termination in the system.
Cause 4: 4-wire equipment connector are not connected well Solution 4: Check the connection.
Problem: Output level is set to max, the audio level from camera end is still too low
Cause: Output level raw adjustment is not proper
Solution: Set output level to ‘Line’, then adjust output level to proper level
Problem: The audio level heard from camera end is too low
Cause: Input level is too low
Solution: Adjust input level by clockwise to proper level
Problem: Hum or buzz in system
Cause 1: Inductive pickup caused by close proximity of this main station or connected remote stations to power lines or transformers.
Solution 1: Relocate the offending unit.
Cause 2: Intercom line cable is not wired properly; the shield of microphone cable is not connected to Pin-1 of the 3 pin XLR
Solution 2: Check intercom line cable. Make sure all the cables’ Pin-1 of 3 pin XLR connect correctly.
V Technical Specification
Bandwidth: 300Hz – 4000Hz ±3dB
Balanced, unbalanced self-adaption
Resistance: >10K ohm Bridge Level: -37dBu-+12dBu (1KHz)
Balanced, unbalanced self-adaption
Resistance: 600 ohm
Level: -43dBu - +8dBu (1KHz)
19” (W) x 1.77” (H) x 6.69” (D), 483mm x 45mm x 170mm