Installation Instructions - PDF

Autodialler Handbook HK1110 issue 2 - PDF


SpheriCall Auto-Dialler

Catalogue No.T173

Adds press button facilities to a standard dial telephone.

Adds a repertory memory store - 10 numbers with up to 18 digits each.

Adds a 'try again' facility.

This simple to install free-standing add-on unit brings important improvements to the ordinary rotary dial telephone.

1. It replaces rotary dialling by press button signalling, thereby simplifying operation and improving accuracy.

2. It has a 'memory' which can be programmed by means of the keys on the unit. This programming requires no technical knowledge.

3. The 'memory' can be programmed with 10 numbers each having up to 18 digits. These numbers may then be 'called' by pressing only two buttons.

4. Another important feature of this remarkable equipment is the 'try again' facility. It always remembers the last number manually keyed, even if the handset has been replaced for an indefinite period, and even if 'stored number' calls are made in the meantime. Therefore, if a number is engaged when first called, it can be tried again any number of times by operating one button instead of complete re-dialling each time. This number remains available until it is replaced by manually keying a further number.

5. No internal alterations are necessary to the existing telephone instrument, and the unit can be used with any type of standard dial telephone.

The 'SpheriCall' is based on MOS-LSI (metal oxide silicone/large scale integrated) circuits, a field in which Pye TMC are particularly experienced, having been the first in the world to apply this technology to telephone equipment.

NOTE: When used with a PABX extension the exchange access digit can be pie-recorded for use with the repertory dialling and 'try-again' facilities.

Dimensions / Weight
Height - 101 mm.
Diameter - 135 mm.
Weight - 1.9 kg.

Pye TMC Stock No. S543777

Technical Data

Electrical Performance
The 'SpheriCall will operate with the following telephone system conditions - Exchange battery voltage (Nominal) 24V, 48/50V, 60V.

The 'SpheriCall' is powered by two six-cell, 150 mA hr, nickel cadmium batteries. These may be charged from 50V or 60V telephone lines, where a bleed current of 3 mA is permissible, or from a mains power supply unit which can be supplied on request.

Period of store sanctity in event of mains failure (battery fully charged) is 60 hours minimum.

Protection has been provided against the effect of large voltage surges occurring on the line.

Handset Position Detector
The unit will not function until the telephone handset has been lifted from the cradle. The on or off-cradle position of the handset is detected by a voltage discriminator connected to the incoming exchange pair. It presents the following input resistance conditions to line - 24V systems = 600k ohms min and 50/60V = 3M ohms min.

Timing Performance
Max. Rate of input keying - 15 digits/sec.
Pulsing speed - 10 or 20 pulses per sec.
Pulse mark/space ratio - 1.6:1 or 2 : 1 break ratio.
Ratio distortion of output pulses - less than 2 mS.
Interdigital pause (l.D.P.) - 10 P.P.S. = 850 50 ms. and 20 p.p.s. = 425 25 ms.
Initial transmission delay = 1 I.D.P.

Pulsing contact - Hermetically sealed, m e r c u r y wetted relay contact, with spark quench circuit of 100 ohms in series with 2.2 MFD.
Dial off normal - Hermetically sealed, dry reed, relay contact.

Connection to line
A junction box can be supplied on request to provide connections to the telephone line. Where mains power is necessary a special junction box incorporating the power unit is available.

Construction Notes
The case of the auto dialler is moulded in plastics and fitted with a non-slip base.  The keypad is mounted on a base plate, the background being a matt black panel. The keys are in gloss black plastics.  The diameter of the unit is 135mm.


1-0 Buttons
Used for manual press button dialling. In addition a pre-selected number can be 'stored' under each of these ten buttons.

Store button
Pressed and released prior to keying in a new 'stored' number.

Interlock Button
Depressed whilst a number is being 'stored'.

Repeat button
Depressed once when calling a stored number, followed by the pressing of the button (1-0) under which the number is stored.  Repeat button is depressed twice to actuate 'try-again' facility.

Cancel Button
The unit is normally switched on and off by lifting or replacing the handset.  However, if a 'stored' number has already commenced pulsing out it can only be cancelled by pressing the cancel button.

Indicator Light
Lights when unit is pulsing out a number.

Current draw
Maximum current drawn from line with telephone 'on-hook' is 3 MA.

Power unit and junction box - switched
Used where line voltage is less than 50V nominal e.g. 24 volt or where powering from the line is not permitted.

Taken from Publicity Leaflet AA/5.74/7M (dated 1974)

To store a number

  1. With phone on hook, press and hold the * button.
  2. Dial #
  3. Dial the chosen store number.
  4. Dial digits to store.
  5. Release *


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Last revised: April 06, 2021