Tremolo Telephone (Telephone No. 9701) is a press button 10 pulses per second signalling telephone intended for
the residential market and others the following facilities:-
- Last number re-dial
- Microphone cut-off (secrecy) Tone caller with two position volume control
- Table or Wall mountable
- Inductive Coupler receiver inset
Made by Northern Telecom and BTCE Cwmcarn (Manufacturers code FWG)
Sale terms only from 1st April 1988
approval number S/1000/3/F/500162
Telephones 9701 have a Ringer Equivalence Number (REN) of 1.
A plastic peg is supplied with the telephone, this should be fitted to the gravity switch
plunger to prevent the handset from falling off the cradle when the instrument is
wall-mounted. The peg is fitted by pushing the two prongs into the holes in the plunger
and snapping off the excess lug. The line cord may be re-routed along the retaining
channels on the base of the instrument alongside the handset cord if required. A 300mm
line cord is also available for wall mounted use.
Line and handset cords are plug ended and may be removed by pressing down the retaining
clip on the plug with a pointed implement and gently pulling the cord.
||BT ITEM CODE
|Telephone 9701 Red
|Telephone 9701 Black
|Telephone 9701 Almond
|Telephone 9701 Blue
|Telephone 9701 Biscuit
|Cord Conn. 4/530 300mm, Silver Satin (Short cord for wall mounted use)
|Cord Conn. 4/531 267mm Almond
|Cord Conn. 4/531 267mm Blue
|Cord Conn. 4/531 267mm Biscuit
|Tremolo Holder Label 1A
|Cord Conn. 4/530,3000mm Silver Satin
|Kit 864A (Wall Mounting Kit - includes, gravity switch peg)
Idle - Normal Capacitor Loop test conditions via the master socket and tone caller
The Tele 9701 draws typically 12 ma line current whilst on-hook to retain last number
re-dial memory, this may result in low resistance loop line test-conditions.
Seized - Normal off-hook press button telephone loop. The electronic keypad and
transmission circuitry may give high resistance telephone-loop line test conditions as with
other press button telephones.
Telephones 9701 receiver insets are designed to provide an inductive coupling effect to
benefit users of 'inductive coupler' behind the ear type hearing aids.
Early version Telephones 9701 (Item coded 870176, 870177, 870163) were withdrawn from new
supply during August 1986 for rework to overcome magnetic problems with the handset.
Later versions (Item coded 877115, 877116, 877117) were withdrawn from new supply during
January 1987 for modification to prevent cords from being unplugged from the telephone
without the use of a tool.
Models that have been modified to overcome this later problem are marked with a yellow
spot on the box and instrument base for identification, models produced during 1987 will
incorporate modified cords on production
Modified and new models will continue with the
existing Item Code numbers.
Tremolo telephones manufactured by Northern Telecom prior to 1986 week 32 have good RF1
immunity from 100kHz to 10Mhz but poor immunity to higher frequencies. Those
manufactured since 1986 week 32 have fairly good RFI immunity from 100kHz to 150Mhz and
may be identified by the year and week marking (i.e. first digits of the eleven digit
serial number) on the base of the telephone.
All Tremolo telephones manufactured by BTCE Cwmcarn have fairly good
RFI immunity from 100kHz to 150Mhz.
Telephones 9701 manufactured before week 43 of 1986 may cause 'repeated digits' to be
pulsed out when making outgoing calls, resulting in `wrong number complaints'. Models made
after this date should not be affected. There will be no dual signalling or MF4 signalling
versions of Tremolo.