The Response 150 is a mains powered, single tape, processor controlled Combined push button Telephone/ Answering and Recording machine. The Response 150 may be desk or wall mounted.  The recording media is a MC60 Micro-cassette.

The facilities for the instrument are as follows:-
  • 13 Number Memory (24 digit)
  • Liquid Crystal Display (10 digit)
  • Latching Secrecy Button (with LED)
  • Last Number Redial (24 digits)
  • Recall
  • Ringer Volume Control (Hi/Lo/Off)
  • Pause Facility
  • Tone/Pulse Switchable by (P/T/TB)
  • REN - 1

The Response 150 facilities are as follows:-

  • Announcement - Up to 2 minutes. Press and hold ANNOUNCEMENT/RECORD CHECK button to record announcement, release on completion.
  • Announcement Check - Press ANNOUNCEMENT/RECORD CHECK button once briefly. Audible alert - Set AUDIBLE ALERT switch to ON if beep required to indicate that new messages have been recorded. There is no beep for saved messages.
  • Volume control must be turned up.
  • Incoming Messages - Up to 3 minutes. Total message time is about 28 minutes using a standard Microcassette MC-60 tape.
  • Memo Message - No limit, up to end of tape. Press and hold the MEMO button to record, release on completion.
  • Message Play - Press PLAY once briefly. This will play all messages and memos.
  • Message Save To save all messages, after The Response 150 has reset to answer or during message play, press and hold the SAVE button until machine beeps once.
  • Sensitivity - NORMAL and LOW, switchable. Preset to normal.
  • Branchphone reset - Will release machine from the line should a parallel telephone handset be lifted. This facility is inhibited for up to 0.5 Seconds when machine first answers, therefore the facility may not always appear to operate.
  • Call screening - Volume Control must be turned up to listen.
  • Pause - Maximum pause is 60 seconds. Press PLAY once while listening to messages, press play again to continue. After 60 seconds pause, the Response 150 resets and all messages are saved.
  • Volume Control - Slider switch, from minimum to maximum.
  • Answer Delay - SHORT answers after 2 rings. LONG answers after 6 rings.
  • Remote switch on - Call machine and let it ring 20 times to turn machine on remotely. Mains supply to machine must be turned on.
  • Time and Day stamp - As long as the time and day have been set an announcement of the time and day will be given after every recorded message.

Made by Team Concepts International Ltd. Made in Malaysia.

Distributed by BT shops, Zones and UK Trade Sales. BT can supply on Sale and Rental terms.

Approval Numbers - Response 150 S/1000/3/N/502549

Approved as supplied for connection to the Public Switched Telephone Network (PSTN) and PBX 2-wire extensions.

The Response 150 is not approved for use on Shared Service lines or as an extension to a payphone. They are not suitable for use on PBX's where manual ringing is applied.

User guides (supplied with the Answering Machine).
Response 150 - TPU 1666

Customer Field Notes. Published as necessary containing any product specific transitory information.

A Phone Socket and a 240 volts, 13 amp, 50 Hertz mains supply is required within 2.5 metres of the Response 150.
The Response 150 is suitable for use on Phone Socket installations on DELs and most types of PBX extensions that provide automatic ringing. The Response 150 has a Ringer Equivalence Number (REN) of 1 and is intended for use in normal Domestic, Residential or Business locations. It is not suited for use in bathrooms or other locations prone to damp or condensation.

Approximate overall dimensions are:-
135 mm x 205 mm x 54 mm, weight 910 grams.

It the machine has failed completely, the output voltage of the Transformer should be checked. The output is marked 9V AC, but will measure about 12volts when tested with the output open circuit.

The user is advised in the User Guide to change the tape at six monthly intervals, turning the tape over once after three months. On each occasion the tape is changed or turned over, the tape head should be cleaned and a new OGM must be recorded.

New units carry a 21 month warranty from the date of manufacture, identified by the first 4 digits (YY WW ****) of the 8 digit serial number marked on the underside of the machine. This guarantee is from supplier to BT.

On-site maintenance of the Response range is limited as the equipment contains no serviceable parts. Some routine servicing - detailed in the User Guide should be carried out by the customer, but field maintenance is restricted to checking the facility switch settings and testing the power unit output.

Several adapters used with Response instruments are marked with lower outputs than those actually measured. Approximate voltage readings (with the output open circuit) are as follows:-
Transformer 19B (marked 13.5V DC) measures 19 - 20v.
Transformer 752 (marked 9V AC) measures 11 - 12v.
Transformer 753 (marked 9.5V DC) measures 13 - 14v.

Description						BT Item Code
Response 150, Alpine White           			870510
(Complete with Transformer)
Message Tape MC 60 Microcassette                        870435
Adaptor 753                                             870505
NB: Adaptor 753 can also be used with the Response 20, 50 and 150



It has been reported that a large quantity of the Response range of TARMs have been returned as faulty without being fully reset and retried. Some faults are caused by quick line disconnects and Radio Frequency Interference and may be cleared by a reset.

Models such as the Response 200, 300, 400, 500 & 1000 have all got a reset button on the underside of the unit. Depressing this button momentarily, using a small probe, will perform a slightly different reset to that performed when the mains is turned off/on. It is suggested that this is performed first, then retry all facilities, before changing out the unit.

However, if after changing the unit the same fault recurs on the new unit, the problem may be site specific and changing the unit again will be of no advantage. If this is the case, please contact the Technical Helpdesk for further advise.

A major problem with Response TARMs recording after a message has been left has been caused by the exchange equipment presenting ‘clicks’ on the line when it is idle. This is due to a modified line card on System X exchanges. BT Labs are aware of the problem and are investigating a cure. Changing the unit will not clear this problem. 

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Last revised: November 02, 2021