CHECKLOG

CHECKLOG is the DOS charge-verification program supplied with the Monolog system. It reads call record files downloaded by DIALOG, applies BT tariff data to calculate the expected charge for each call, and produces a printed analysis for comparison against a disputed bill. Version 1.2 was the release supplied with the Monolog system.

What it does

Reads call record files downloaded by DIALOG
Applies BT charge bands, charge rates and timing data
Identifies free numbers, special prefixes and public holidays
Produces a printed charge analysis with per-call and summary totals

CHECKLOG v1.2 — Supplied Files

Version 1.2 of CHECKLOG was supplied as a set of files covering the program itself and several national tariff data files. The data files used a numbered extension scheme — the asterisk in the filenames below represents a version digit that incremented with each tariff update.

Filename	Description
CHECKLOG.EXE	The CHECKLOG program itself
CHECKLOG.C0*	Dial code / Charge Group assignments — maps dialling prefixes to charge groups and place names
CHECKLOG.N0*	National Charge Data — maps dialling prefixes to charge band numbers
CHECKLOG.T0*	Charge band timing patterns — defines Cheap, Standard, Peak and Economy periods across the day for each tariff pattern
CHECKLOG.U0*	National dial codes and place names — detailed lookup of exchange names by dialling prefix
CHECKLOG.HOL	Public holidays — dates treated as Sunday for tariff purposes

File Formats

CHECKLOG.C0* — Dial Code / Charge Group

Each record maps a charge group code and place name to a dialling prefix. The charge group code (e.g. NW010) identifies the originating district, used to determine the applicable charge band when combined with the national charge data.

CHECKLOG.C01 — extract

NW010 CLITHEROE 0200 SW009 BOURNEMOUTH 0202 MT010 COVENTRY 0203 NW005 BOLTON 0204 MT004 BOSTON 0205 ET018 COLCHESTER 0206 NE015 CONSETT 0207 SW008 BODMIN 0208 SW056 REDRUTH 0209 MT003 BIRMINGHAM 0212

CHECKLOG.N0* — National Charge Data

Each record maps a dialled prefix to a charge band number. The charge band number is then cross-referenced with the timing data in CHECKLOG.T0* to determine the applicable rate. Shorter prefixes act as catch-all entries — a longer match always takes precedence.

CHECKLOG.N01 — extract

03993,32, 03994,32, 03995,32, 03996,1, 03997,1, 03998,1, 03999,1, 04,3, 04260,32, 04266,32, 04267,32, 04268,32, 04269,1, 04306,32, 04591,2, 04592,2, 04593,32,

CHECKLOG.T0* — Charge Band Timing Patterns

Defines the tariff pattern for each charge band. The 24-hour day is divided into 48 half-hour segments. Each character in the pattern string represents one half-hour slot and indicates whether that period is Cheap (C), Standard (S), Peak (P) or Economy (E). Up to 9 tariff patterns (TP1–TP9) are supported; version 1.2 uses 6.

CHECKLOG.T01 — extract

TARIFF PATTERNS current range 1-6, permitted range 1-9 C=cheap S=standard P=peak E=economy 24 hrs divided into 30 minute segments <midnight______________________________midnight> 000000000000000000001111111111111111111122222222 001122334455667788990011223344556677889900112233 :::::::::::::::::::::::::::::::::::::::::::::::: 030303030303030303030303030303030303030303030303 000000000000000000000000000000000000000000000000 TP1 CCCCCCCCCCCCCCCCSSPPPPPPPPSSSSSSSSSSCCCCCCCCCCCC TP2 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC TP3 CCCCCCCCCCCCCCCCSSSSSSSSSSSSSSSSSSSSSSSSCCCCCCCC TP4 SSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS TP5 CCCCCCCCCCCCCCCCSSSSSSSSSSSSSSPPPPSSSSSSCCCCCCCC TP6 EEEEEEEEEEEEEESSSSSSSSSSSSSSSEEEEEEEEEESSSSSSSSS

CHECKLOG.U0* — National Dial Codes / Place Names

A detailed lookup table mapping dialling prefixes to exchange names and locations. Used by CHECKLOG and PRINTOUT to annotate call records with the destination exchange name. Longer prefixes provide more specific matches — e.g. 020247 resolves to Christchurch rather than just Bournemouth.

CHECKLOG.U01 — extract

0200 CLITHEROE Lancs 020042 MERCURY COMMS, CLITHEROE Lancs 020045 Gisburn CLITHEROE Lancs 02006 Slaidburn CLITHEROE Lancs 02007 Bolton-by-Bowland CLITHEROE Lancs 02008 Dunsop Bridge CLITHEROE Lancs 0202 BOURNEMOUTH Dorset 020247 CHRISTCHURCH Dorset 020248 CHRISTCHURCH Dorset 020250 MERCURY COMMS, BOURNEMOUTH Dorset 020260 BROADSTONE Dorset 020262 Lytchett Minster POOLE Dorset 020263 Lytchett Minster POOLE Dorset 020267 POOLE Dorset 020268 POOLE Dorset 020269 BROADSTONE Dorset

Charge Group Data Files

In addition to the national files, CHECKLOG used per-district Charge Group data files — one file per originating exchange area. These combined the charge group header with the national charge data specific to calls originating from that district, allowing CHECKLOG to determine the correct charge band for any given dialled number from that location.

Each file was named using the charge group code as the filename and a version number as the extension — for example ET002.V05 for revision 5 of the Attleborough charge group data.

ET002.V05 — Charge Group Data File (Attleborough)

ET002 ATTLEBOROUGH 0953 0263,2, 0284,2, 0328,2, 0353,2, 0359,1, 0362,1, 0366,2, 0379,1, 0449,2, 0473,2, 0485,2,

Constraints & Notes

CHECKLOG runs best from a hard disk — searching the national place names file (CHECKLOG.U0*) from floppy is slow due to its size. If a maths co-processor is installed and causes an error at startup, add SET 87=NO to AUTOEXEC.BAT to force the program to ignore it.

Like DIALOG, CHECKLOG is a 16-bit MS-DOS application and will not run natively on a 64-bit operating system. DOSBox or a similar DOS emulator is required to run it on modern hardware.

⬜

Sample CHECKLOG Output

Annotated printout example to be added