LOUDSPEAKING TELEPHONE No. 8


Introduced in 1981.

TELECOM INSTRUCTION
C MARKETING INSTALLATION
3 Internal
B2007
Issue 1, May 1982

LOUDSPEAKING TELEPHONE No. 8
("ACCORD" Loudspeaking Telephone)

INTRODUCTION
The Loudspeaking Telephone No. 8 (commercial description "Accord") is a press button telephone that enables the customer to initiate (on-hook dialling) and answer calls in a "handsfree mode". Operation of the LST 8 in this mode gives full voice-switched loudspeaking telephone facilities. it is available in 10 pps (LST 8A), MF (LST 8B) and DC 'C' Code (LST 8C) versions.

DESCRIPTION

General
The LST 8 measures 200 mm long, 372 mm wide and 90 mm high and weighs 2.8 Kgs.

It is available in three different case colours, dark brown, light grey and mid-grey (LST 8C only available in mid-grey) and is supplied with:-

(a) A 6-way line cord 3 metres in length.

(b) A 13-amp, 3-pin 'plug type' transformer (Transformer Unit 17A) similar to those supplied with pocket calculators. This transformer unit is connected to the LST 8 via a 3 metre power cord. The Transformer Unit 17A measures 47 mm wide, 56 mm deep, 54 mm high and requires at least 30 mm headroom above the top of the socket outlet.

The LST 8 can be used in two different ways:-

  • As a normal telephone using the handset and keypad.
  • As a "handsfree" loudspeaking telephone using the right hand half of the unit and keypad.

2.2 Keypad
The keypad contains the normal 1 - 0 keys for dialling, # & * are only used on the LST 8B and LST 8C versions. Beneath the keypad are 5 keys which are used for:-

  • [R] Register Recall (Timed Break)
  • [H] Earth Loop Recall
  • [M] Call Main (Plan 105/107)
  • [E] Call Extension (Plan 107) or Shared Service-Call Exchange
  • [-] Spare

On the left hand side of the telephone unit there are three keys for controlling the loudspeaking element of the LST 8. The keys are:-

  • [ON] switches the loudspeaker and microphone into the exchange line. (Red LED glows.)
  • [OFF] switches the loudspeaker and microphone off the exchange line. (Red LED extinguished.)
  • [m] is Microphone Mute

There is also a loudspeaker volume control situated slightly above and to the left of the Microphone Mute key.

Tone Ringer
Incoming calls are indicated by a tone ringer similar to that found in the Trimphone. The tone ringer volume control can be found on the bottom of the rear of case on the left hand side. Tone ringer 'OFF' is provided by withdrawing the screw on the volume control in a similar manner as for the Trimphone.

Telephone Number Label
The number label is a keyphone type and is situated under the clear plastic label holder found above the keypad.

FIELD OF USE
The LST 8 can be used on the following plan configurations:-

  • Direct Exchange Lines
  • Extensions on a PMBX 2/ , 3/ and 4/ switchboards
  • Extensions on Earth Recall PBXs
  • Internal extension on a Plan 107 or 105 (NOT AS MAIN)
  • Extension on a Plan 1A
  • Shared Service Line
  • Phone Socket (with modifications)

OPERATION
To make a call as a Lift the handset and call the number ordinary telephone. required.

To make a call - Handsfree.
Press [ON] key - dial tone will be heard from the loudspeaker. The volume of the loudspeaker can be varied by the rotary control knob.
Call number required.
To release the call at the end of conversation press [OFF].

Answering a call.
The call can either be answered by lifting the handset or pressing the [ON] key and speaking into the microphone. (Handsfree.)

Transferring a call from the handset to loudspeaking telephone.
Press [ON] key and replace handset. NOTE: The call will not be heard on the loudspeaker until the headset has been replaced.

Transferring a call
The action of lifting the handset will from loudspeaking automatically transfer the call onto telephone to the handset. handset.

Terminating a call
To terminate a call originated by using the handset requites replacement of the handset. To terminate a call originated in the handsfree mode press the key.

INSTALLATION
The LST 8 should be installed in accordance with Diagram N4479.

Phone Socket (Plug and Socket)
The LST 8 is suitable to be connected using a Phone socket except when requiring a 12-way line cord i.e. as an internal extension of a Plan 107. The conversion from the existing spade ended line cord to plug ended line cord should be carried out locally using a Cord Connecting 6/502.

Plan 107/105 (Internal Extension)
When the LST 8 is used as an internal extension to a Plan 107/105 a KIT 477A is required. The KIT 477A consists of the following items:-

Cord Instrument No. 12/16AT 3000 mm
Buzzer 32C-4 Block
Terminal No. 36B

The Buzzer 32C-4 is fitted to the two pillars situated on the rear panel of the case (just above and either side of the cord retaining plate .

To remove the line cord, in order to replace with a 12-way cord or Cord Connecting 6/502, press down on the plastic tongue situated beneath the cord retaining plate with a suitable instrument eg Screwdriver Instrument No. 2. With this tongue depressed push the cords from the rear, the bottom edge of the cord retaining bracket will lift enabling the bracket to be eased out.

To replace the cord retaining bracket slot the top edge under the lip and press the bottom edge over the plastic tongue using the Screwdriver Instrument No. 2.

Jack Unit 6A
This unit is used to enable additional loudspeaker (Loudspeaking Unit No. 4B-1) and microphone (Microphone Unit 1B-1) to be connected to the LST 8. The Jack Unit 6A consists of all necessary wiring to enable the unit to function. The jack fits into the slot situated in the rear of the case to the left of the loudspeaker (once the blanking piece has been removed). The associated wiring is plug ended and should be plugged into the appropriate jacks on the loudspeaking circuit board. The jacks are marked "EXT. MIC" and "EXT. L.S" and are situated to the left of the speaker.

TESTING
The following tests in the table below should be applied to ensure that the unit functions correctly. If the telephone is found to be faulty change the instrument complete.

	STEP 	PROCEDURE 			INDICATION

	1	Make outgoing call		Ringing tone heard and on the 
		using the handset to 		call being answered conversation
		test centre number		can take place.
		and speak to testing
		officer.

	2	Press the [on] key.		The call is transferred onto the
						loudspeaking unit and conversation
						can continue.
		Test that the microphone mute,
		volume control and tone ringer
		function in all three tone
		ringer volume positions.

	3	Replace the handset.
		Press the [off] key.		The call is released. 

If the LST 8 has been used in a plan configuration the relevant facilities of that plan number must be tested in addition to the above table of tests.

RECOVERY
The following item should be recovered and returned to stores:-
Loudspeaking Telephone No. 8 (LST 8A, B or C) [Including the Transformer Unit No. 17A]

References:
Maintenance TI E5 B2809
Diagram N4479

   

 
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Last revised: December 18, 2010

FM