Audio
Training Guide

1. SDK audio door entry kits
2. KET audio door entry kits
3. Doorpoint door entry kits
4. Vandal Resistant audio door entry kits
5. Quick Reference
6. Vandal resistant audio door entry systems
   
   1. Overview
   2. VR engravable Panels
   3. VR Name Window Panels
      
   4. VR Modular Panels
   5. SRS Power Supplies
   6. SRS Telephones
   7. SRS Cabling
Trouble shooting

Call Signal
Speech
Locking

Video
Access Control
Electric Locking

Before continuing it is important to have an understanding of the function of the various cables of the system.

1. Terminal 1 at the telephone is connected to the speaker unit terminal 1 carries the amplified signal from the microphone in the door entry panels to the speaker (earpiece) in the telephone. The telephone makes the connection when the handset is lifted.
   
   
2. Terminal 2 at the telephone is connected to the speaker unit terminal 2 and carries the unamplified signal from the microphone (mouthpiece) in the telephone to the speaker (amplifier) in the entrance panel. The telephone makes the connection when the handset is lifted.
   
   
3. Terminal 9 in the telephone is connected to terminal 9 of the 9307.2 power supply unit. When the lock release button on the telephone is pressed, terminal 9 and terminal 6 on the telephone are short circuited. This causes the timer in the 9307.2 power supply to be triggered and the relay to change state.
   
   
4. SRS systems are normally connected for tone call, although they can be configured for buzzer call. The circuit is as follows. A tone is present at the C terminal of the 9307.1 power supply. C is connected to the common of the call buttons at the entrance panel. When the call button is pressed the call tone signal continues to terminal C7 at the telephone. This is connected to the speaker (earpiece) of the handset when the phone is on the hook. When the phone is lifted off the hook the circuit is broken.
   
   
5. Terminal 6 in the telephone is connected to -ve of the speaker unit (amplifier) and from there to 0v of the power supply. It must be connected to the speaker unit before the power supply. The wire connected to 6 on the phone is the common negative connection. Nothing will work correctly on the telephone without this connection.

1. Check for 12v dc at the speaker unit (amplifier) power terminals.
2. If power is OK. Connect a telephone locally to the entrance panel on a short cable.
   • Only connect power (as above) and 1, 2 & 6 on the phone to 1, 2 & -ve respectively.
   • Do not connect the rest of the system.
   • If the local telephone works correctly then you may have a wiring fault.
   • If you are sure your local connections are correct and still have a the same fault then the speaker unit (amplifier) is more likely to be faulty, simply because it is a more complicated electronic product than the telephone. If you have a spare telephone repeat this test.

• Check function of the amplifier and telephone, follow instructions for No speech in either direction.
• If the speech is acceptable after the above test it is likely that you have a cable fault

Speech volume is too low

• Adjust amplifier volume controls
• Check cables for short circuit and follow instructions for No speech in either direction.

Speech is accompanied by high pitched whistle (feedback)

Causes


• excessive internal amplification (Volume requires adjustment) and / or
  
  
• excessive external amplification (Volume requires adjustment) and / or
  
  
• power supply too high (Check for 6volts to + terminal on amplifier) and / or
  
  
• poor alignment of microphone to hole in entrance panel plate and / or
  
  
• incorrect cable used on long cable run (telephone cable - solid core twisted pairs should be used for
  all installations)
  
  
• The sound detected by the microphone in the entrance panel is amplified and sent to the earpiece in the telephone. Assuming that the correct power supply, speaker unit and telephones are used, then either :
  
  
• The microphone in the telephone handset then picks up the sound and sends it to the speaker amplifier, where it is amplified once again. and / or
  
  
• The cable from the microphone in the telephone picks up interference and introduces the interference to the loop.
  
  
• In either case above the phone and speaker unit emit a loud high pitched whistle feedback.
  

The Cure


• The correct cable for telephone installations is CW1308, twisted paired, solid core cable. You should run the speaker (phone terminal 1) with the negative (phone terminal 6) as a pair the microphone (phone terminal 2) with the negative (phone terminal 6) as a pair.
  
  
• This effectively puts a negative screen around the sensitive audio wires and helps separate the audio wires from interference.
  
  
• The practise of using standed (alarm) cable often makes the situation worse and should be avoided.

1. Check the wire from terminal 1 on the telephone.
2. If you cannot find a fault, follow instructions for No speech in either direction.
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   

1. Check the wire from terminal 2 on the telephone.
2. If you cannot find a fault, follow instructions for No speech in either direction.