PXML No. 63
APPROVAL No. S/1000/GF/1981/PR

See also Herald A and Pentara 100+

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Sales Brochure (Pentara 100) - MER193

TX58 TX57

Herald C is marketed as:-
Merlin S5102 - Herald C Software V8.3 with TX51-54 Terminals
Pentara 100 - Herald C Software V8.3 with TX54-58 Terminals
Pentara l00E - Herald C Software V8.4 with TX54-58 Terminals

Herald C Plus is marketed as:-
Pentara +Plus - Herald C Plus Software V10.0 with TX54-58 Terminals (Ice Grey) and TX65-69 terminals.

All the above Herald systems may use the Terminal TX52 PF (Power Fail) when required.

The Herald C Plus was marketed as the Pentara +Plus Phone System. A further enhancement of the Herald systems, it incorporates the existing features and facilities of the previous Herald generics, plus some additional ones.

The introduction of ver 10.2 (build No 7944) software in February 1992 allowed the use of a Visually Handicapped Operators Console (VHOC). The Console, incorporating a speech synthesis board, is a modified TX68 with a Plantronics headset.

A standby battery shelf was available for new installations and systems upgraded to Pentara +Plus. Typical standby time is between 40 minutes (Single Battery, 3 Shelf System) to about 6 hours (3 Batteries, Single Shelf System). When providing standby power, only Power Units SA20554 may be used in the extension shelves.

Systems can be configured in Herald Assembly Centres using Pentara Documentation System (PDS) or on site using the Self Configure option. Once installed, system and extension facilities can be altered by the customer.

The Pentara Plus Phone System is intended for new customers. Existing Herald A, 100B, B8, S5102, Pentara and Pentara l00E systems can be upgraded to Pentara Plus.

Made by Philips Business Communications Systems

Approved for direct or indirect connection to the PSTN and LD or MF4 signalling by working as a (List B or D) subsidiary system connected to a (List C) system.
Recall can be Earth Loop (300ms) or Timed Break (66ms or 300ms).


Herald C processor ASU 1A1/SA20552:-
Version 8.3A
Version 8.3B
Version 8.4 (IC 10-15 & 6-7 are marked with the software identification)
Version 8.4A
Version 8.4C
Version 8.4D
Version 8.4E
Version 8.4F

Herald Pentara Plus ASU 1A1/SA20579:-
Version 8.A, 8A.AF
Version 10.0B, 10C (IC 10-13 are marked with the software identification)
Version 10.1, 10.2

Call Logging ASU 1A1/SA20572:-
Version 2.5) IC 22 For use only with processors fitted with v8 software
Version 2.7)
Version 2.8)
Version 10.1 (For use only in association with processor 1A1/SA20579 fitted with V10 software)

Speech Synthesis Card SA 20567:-
Version 3.1 IC 3 marked V3.1
Version 1.0 IC 7 marked Vl.0
Version 1.2 IC 7 marked V1.2 - Pentara +Plus
Version 5.1 IC 7 marked V5.0 - VHOC additional board

Music on Hold Card SA 20568:-
Version 3.0 IC 1 marked V3.0
Version 1.0 (The Entertainer) IC 7 marked V1.0
Version 2.0 (Greensleeves) IC 7 marked V2.0


Title Marketing Name launch Date Approx sales
Herald A Herald (A) Apr 1981 22,000
Herald B (v5) Herald 100B Apr 1983 18,000
Herald C (v8.3) Herald S5102 Sept 1984 2,000
B8 upgrade B8 upgrade Dec 1984 *
New low profile terminals Pentara 100 Apr 1985 *
v8.4 software Pentara 100E Jan 1986 *
v10 software Pentara +Plus Jan 1989
* 14,000 until Jan 1988

Merlin Pentara 100
British Telecom has built on the experience gained of over 40,000 Herald telephone systems in operation by designing its successor the Merlin Pentara 100. This new system provides all the features of its predecessor and more in a completely redesigned package.

The immediately obvious difference is the range of new low-profile terminals, which incorporate programmable function buttons, integral monitor speaker and variable ringing pitch. Facilities incorporated in the range also include full two-way loudspeaking and a liquid-crystal display to provide operational information to the user. The less obvious differences lie in the software of the system, which provides many of the features.

Apart from such regular features as abbreviated dialling, call diversion, conference and hands-free calling, the Pentara allows users to carry out their own changes in facilities. And, to ensure that changes are correctly implemented, the system includes speech synthesis to provide spoken messages to the user. This feature also allows users to check the facilities available on a particular telephone at the time of use.

Other facilities available with the Pentara 100 system that are designed to aid operation in business situations are call queuing, call hold and ring back when free. This last feature avoids the frustrations of having to try repeatedly to call a busy extension by doing this job automatically and ringing the caller when the extension is free.

The Merlin Pentara 100 has capacity for up to 16 exchange lines and 76 extensions, although there is some flexibility in these maxima depending on individual requirements. The system can be configured either as a key system, where any terminal can answer incoming calls or, by providing an operator's terminal, as an operator-controlled system.

Taken from British Telecommunications Engineering, Vol. 4, July 1985


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