TRIMPHONE Sales Circular

DF 280
A&PRD Circular ITD/MB

15th November, 1965


A new deluxe design of telephone

1. This circular introduces the above telephone which initially will be the subject of a small market trial in London NW Area (see para 3). Sales Information Note 5/65 gave advance information about the instrument. The corresponding Engineering Instruction at present is Works Specification S/W 2072. Details of the instrument wore also released on 10th May 1965 in a Press and Broadcast Notice. The commercial name TRIMPHONE is derived from the initials of the description Tone Ringing Illuminated Model.

2. Description and facilities - The telephone is a lightweight instrument weighing only 2 lb. It is 7.5" long, 4.25" wide and  4" high. Colours are as follows:-

Telephone Base  Handset
Two-tone blue Light blue  Dark blue
Grey/Green Middle grey  Olive green
Grey/White Off-white Light grey

In place of the conventional bell the telephone has a tone caller, a built-in electronic device which produces a high. pitched. intermittent warbling note (see Card A 3717 giving operating instructions, which was distributed in June 1965). The tone-caller has a three-position switch which allows the tone to be sot at soft, medium, and loud. In the medium and loud positions the tone starts quietly and builds up to the appropriate volume in about 10 seconds. Market research has shown that most people regard this tone as an agreeable change from a boll. The dial has a transparent finger plate with letters and. figures beneath the finger holes and. is permanently illuminated, from within by a miniature self-energised. fluorescent tube which does not require a power supply. The level of illumination is adequate to make the dial easily visible in a darkened room. Other features of the telephone are its lightweight handset, which rests neatly but unconventionally over the dial, and an instrument cord. extensible from 4' 6" to 9'.  A photograph of the telephone is at Appendix A; the design and colours have boon approved. by the Council of Industrial Design.

3. Marketing Policy - The initial supply is for 1,000 telephones in white only and. with no press-buttons. This imposes limitations on their suitability for use on shared service lines, or with other telephone apparatus, full instructions on which have been sent to NW Area. None of these telephones will be used outside NW Area except on specific instructions from Headquarters. If enquiries are received in other Areas information may be given about prices, colours, etc. Enquiries about availability should. be recorded so that they can be followed. up when stocks are available, but it should. be explained that a small quantity only are on market trial in NW London and that it is regretted. that for the time being supplies are not available elsewhere. The manufacture of a further 9,000 telephones, in all the colours mentioned in para 2 and with provision for one press button whore required, will begin before the end of the year and, dependent on demand in NW Area, it may then be possible to extend sales to a few other selected Areas.

Further orders will be based on marketing experience, and. it is expected that Trimphone will be available generally by the end of 1966.

4. Sales Leaflet.- An illustrated leaflet (PH1048) has been prepared and a small supply sent to each Area without  requisition.

5. Tariffs and Insurance

5.1 Modern -telephone charge - £1. For the purpose of his charge the Trimphone should be regarded as a modern telephone, the charge to be applied on the same basis as for other modern telephones in TpSI BI V. If a Trimphone is ceased it may be replaced. by a modern table or wall telephone without modern or change of apparatus charge.

5.2 Quarterly rental - 7s. 6d. This rental is additional to any other standard charges payable for the installation.

5.3 Minimum term of agreement - one year.

5.14. Change of apparatus charge - as in TpSI B5 IV 9-12.

5.5 Removal charges - as in TpSI B5 IV 5.3 and 6.

The charge in 5.2 is in the Telephone Amendment (No. 1) Regulations 1965, and installations should therefore be
provided on Applications or Agreements as required in TpSI B4.

5.6 Insurance value - £20.

6. Requisitions - Separate requisitioning instructions have been sent to NW Area. Instructions will be issued. later regarding requisitioning arrangements for other Areas.

7. Any enquiries about this circular should be made via RDs (TB) to ITD/MB/SAD - Mr. C. F. Plane, HEAdquarters 4665.

8. This circular should be cancelled when the relative amendments to TpSIs B1, B5 and. H20 are received, or on 31st October 1967, whichever is the earlier.

Reference to earlier circulars - None.



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