Installation

CT54 Mounting

The CT54 is mounted to the Kiosk backboard using five M8 x 40mm button head hex screws. Attached to the rear of the backboard are five corresponding M8 cage nuts located within a slotted metal plate, to allow proper alignment of the Payphone when it is installed in the Kiosk.

Wiring (AC Power Supply)

The CT54 requires 3 separate connections; AC Power, a Telephone line and a Ground/Earth connection. These are made via a 5-way screw terminal block marked as TB1 on the interface board. The connections are marked left to right as "AC AC A G B"

The Payphone requires an AC (or DC) power supply in order to function correctly and this should be connected to the two terminals labelled "AC", on the Green Terminal Block TB1 (terminals 1 and 2).

The proper AC power source is a 10V AC 500mA/5VA adaptor, however the author used a 25VA 12VAC transformer, which also appears to work adequately well. On-board the Revision 'B' PCB, there is an LM2941 positive voltage regulator which has an input operating voltage range between 6V to 26V, so it is assumed that the Payphone could also work on anything up to around 24V AC. Any power supply that exceeds this would more than likely cause permanent damage to the electronics.

NEVER connect the Payphone directly to the UK AC mains supply voltage

Once power is applied to the Payphone, the red LED (if fitted) on the Interface PCB should illuminate. If it doesn't, the interface PCB has a PCB mounted resettable fuse (F1) located on it. This is a Bourns 0.3A hold current, radial leaded 60V fuse (RS stock number 647-8465). Check this component for continuity and replace it if necessary.

Wiring (DC Power Supply)

6V battery packs and wiring harness

The CT54 can also be powered from a DC battery power source. Presumably, there are some Kiosk installations that do not have access to a mains (240V) power source and in these instances, a pair of 6V 1.0Ah sealed rechargeable batteries connected in series are wired to the AC terminals on the payphone interface board using a CT54 Battery cable (Item code: 039776). This cable also has a built in 500mA PICO axial lead fuse for protection.

When the Payphone is DC powered, in order to preserve battery run-time, the idle message - "BT PAYPHONES/LIFT HANDSET" - shown on the Payphone display is suppressed. In addition, the Revision 'C' systems don't appear to be fitted with an internal LED , again, presumably to prolong battery life. Based on the dates taken from a BT Payphone Maintenance Log card, it would appear the batteries will typically last 12-18 months but this will largely be dependant on the usage pattern of the Payphone.

500mA In-line PICO fuse

6V 1.0Ah Rechargeable battery

Wiring (Telephone Line)

Ordinarily a telephone line is connected to the terminals marked as 'A' and 'B' (terminals 3 and 5 on connection block TB1). It is not however recommended to connect the Payphone to a working BT (or other providers) phone line directly for a number of reasons;

If the Payphone is incorrectly wired, then it may cause damage to the Telephone line which could incur a call-out fee from your service provider to repair the fault.
The Payphone will probably have the BT Payphone Management System ("IPOMS" I think it might be called) telephone number stored in it. Periodically, the Payphone will attempt to dial back to IPOMS to send reporting data and collect tariff updates etc. This could incur costs on your telephone bill (depending on your calling package). You probably also don't want the Payphone constantly trying to call back to the "mothership" whilst you're busy chatting on the phone either!
Finally, BT probably don't want old de-commissioned Payphones constantly trying to call back to their management system. I don't have any inside knowledge of this system though but I'd expect as part of the PPP negotiation, not only will it perform PAP authentication but it will also probably validate the Calling Line Identity (CLI) since each payphone has the same authentication credentials hard-coded within the firmware.

Coin Vault

Mounted beneath the Payphone is the Coin Vault (Compartment Cash No. 5A) or "Fort Knox Case" and within this is a Cash Container No. 12. The coin vault is fitted with a Lock 59B, made by Kaba locks of Taunton. I think there are different lids that can be fitted to the coin vault - the one shown below is what is called a "Low take lid" (presumably this lid has less protection than its "High take" equivalent?). The lid is held in place by 4 x 8mm locking bars which engage with 4 corresponding lugs on the cash compartment. In order to open the vault, the Key is inserted into the lock and rotated 90O anti-clockwise. This engages the rotary cam which allows the locking mechanism to be actuated by inserting a T-bar into the winding mechanism. The key cannot be removed until the locking bars have been re-locked. If required, once un-locked, the lid can simply be lifted off the spring-loaded hinge arms.

Compartment Cash No. 5A with Container Cash No. 12 fitted

Cash Container No. 12

The Cash Container No. 12 is located within the Cash Compartment and comprises of a hinged, lockable lid which incorporates a coin slot at the top that automatically closes as the Container is removed from the payphone. When the Cash container is unlocked, the spring-loaded cover retracts and the coin slot then opens again. The Cash container is fitted with a Lock No. 60.

These containers tend to be hard to come by since I understand they are destroyed by BT but occasionally they do appear on popular auction sites such as eBay.

Cash Container No. 12

Mains Electrics

The electrical switchgear for the Kiosk light and payphone are mounted to a Plywood board measuring 180mm (width) x 415mm (length) x 10mm (depth). This is bolted via 4 screws, to the rear of the Kiosk and protected via either a Plastic (Curved) or Metal (Square) Powerguard.

Air Freshener

OK , so this isn't strictly payphone related I appreciate, but it does relate to K6 Kiosk so is kind of linked ! A number of K6 Kiosks these days have been fitted with air fresheners.

These are usually installed in the top left hand corner of the backboard and are painted black. They comprise of a metal box, 26cm tall, 12cm wide and 7.5cm deep secured by two security bolts.

Inside is a commercially available electronic air freshener unit (Airoma IPE) that squirts a dash of fragrance into the kiosk every 15 minutes.

The unit is powered by 2 alkaline D-Cell batteries which are fitted into the base of the unit and should last around 3 years.

The canisters used are "Airoma Spray Can (Cool)" (BT Item code 019929) 270ml and are available for around £5 from auction sites or on-line stores. These hold around 3,000 'squirts' of freshener. There is a sensor switch at the top of the unit that detects whether the canister is present or not.

The plastic air freshener unit is fastened inside the case via 2 bolts and the entire metal box is then fastened to the backboard via a metal plate. The bottom two mounting holes are used to screw the unit to the backboard and the top hole is used to bolt the unit to the back plate. The entire back plate then hangs off the rain gutter lip, underneath the rear 'Telephone' glass.

Sadly, I don't recall seeing a working Air Freshener in any kiosk. They have either been vandalised or I imagine the canisters and/or batteries probably don't get replaced these days.