Model Electronic Railway Group

The Leading Society for Model Railway Electronics

Over 50 years of Innovation: 1967-2021

Technical Bulletins

MERG produces Technical Bulletins covering a wide variety of topics - the full list of the currently available TBs are detailed below. Download facilities are available to Members in the Members Area

AncillaryTOP OF PAGE
A01/01 A high frequency oscillator (68.9 kb)  
A01/02 Construction & use of HF Oscillator to A1/1 (50.0 kb)  
A03/01 Point motor capacitor discharge power packs (20.8 kb)  
A05/01 Sustained Tail Lamps (21.9 kb)  
A06/01 Point motors: types, operation & indication (98.4 kb)  
A06/02 Comparative tests of three Motor-driven Point Motors (18.4 kb)  
A06/03 'Tortoise' Slow Motion Switch Machine (Point Motor) - Data Sheet (134.4 kb)  
A07/01 Reed switches (41.1 kb)  
A07/02 Hall effect switches (39.7 kb)  
A07/03 Magnets - use with Reed and Hall Effect Switches (39.2 kb)  
A08/01 Fast recharge capacitor discharge unit (20.5 kb)  
A09/01 Capacitor discharge units using transistors (Issue 2) (47.3 kb)  
A10/01 Light Emitting Diodes (LEDs) (274.5 kb)  
A11/01 Twinkling gas lamps (303.2 kb)  
A11/03 Flaming Hot Air Balloons, another use for twinklers (88.1 kb)  
A12/01 Motorised turntable control unit(see also A17/1) (23.5 kb)  
A14/01 A Measured Pulse capacitor discharge unit (91.5 kb)  
A15/01 Meters - in model railway service (55.2 kb)  
A15/02 Meters - interpreting the readings (58.1 kb)  
A15/05 Connecting Meters to a Pentroller (58.2 kb)  
A16/01 The 'Heiniken' track cleaner (20.6 kb)  
A16/02 The 'Flying banana' motored track cleaner (42.7 kb)  
A17/01 Turntable Operation using SCRs (see also A12/1) (43.4 kb)  
A17/02 Turntable indexing using an Infrared photoreflective sensor (515.7 kb)  
A18/01 Welding Arc Simulator (using CMOS) (25.6 kb)  
A19/01 High Frequency Train Lighting (and Train-on-Track Indication) (33.1 kb)  
A19/02 A High Quality Sine Wave generator (41.8 kb)  
A20/01 The MERG Simple Shuttle (Demonstration track) (47.3 kb)  
A21/01 Low Cost Current Display using a LED bargraph (36.7 kb)  
A23/01 An Overload protected Controller Output stage (21.7 kb)  
A24/01 Road Traffic Lights sequencer (27.0 kb)  
A25/01 A Touch Switch for Control panels (47.1 kb)  
A26/01 Servo Motor Driver (applied to loco water crane swing in & out!) (29.6 kb)  
A29/01 Single Wire Point Motor Switching Unit (54.5 kb)  
A30/01 Matrix Operation of Point Motors (48.7 kb)  
A31/01 Matrix Control for Point Motors (20.1 kb)  
A32/01 A Fast Analogue Clock (23.6 kb)  
A32/02 An Analogue Scale Time Clock (77.3 kb)  
A33/01 Section Isolating Switch with Isolation and Occupation Indication (33.0 kb)  
A33/02 Pulse generator for Isolated/occupied indication (24.3 kb)  
A34/01 Development of a Dual Point Motor (Solenoid type)Driver (50.8 kb)  
A35/01 Instrumentation for a 7 1/4" Gauge Battery Loco (24.8 kb)  
A36/01 The Faller Road System - Introduction (28.0 kb)  
A36/02 The Faller Road System - Route Selection and Parking (64.4 kb)  
A38/01 Programmable Servo Driver type "Servo 4" (66.6 kb)  
A38/02 Setting Box for ‘Servo 4’ Driver Board (115.9 kb)  
A39/01 A Simple RFID Reader Module (117.0 kb)  
A39/02 Putting RFID to Work 1 - Basic Principles and Installation (318.6 kb)  
A40/01 Stepper Motor Turntable Controller (288.3 kb)  
A40/02 Putting the Turntable Controller (Stepper Motor) Kit 79 to Use (1,383.7 kb)  
A41-01 Putting the Megapoints Servo Controller to Use (1,012.7 kb)  
ComponentsTOP OF PAGE
B01/01 Preferred Values for electronic components (31.7 kb)  
B02/01 Resistor colour coding (43.3 kb)  
B04/01 A Summary of Op Amps (24.2 kb)  
Comp./Command ControlTOP OF PAGE
CC02/01 The Interlocker System (Computer Control of Model Railways) (32.3 kb)  
CC02/02 The Interlocker System - the Hardware (Issue 3) (42.7 kb)  
CC02/06 The Signalman System (Peter J. Day M508) (67.9 kb)  
CC02/11 Computer Control in the Vale (Pendon Museum) (17.8 kb)  
CC03/01 The I2C Interfacing system and its relevance to Model Railways (28.4 kb)  
CC04/01 Command Control Route Indication (40.5 kb)  
CC04/02 Command Control Train on Track Indication using MERG TOTIs and Power supply (30.0 kb)  
CC05/01 The Airfix Multiple Train Control System (181.4 kb)  
CC21/01 Route Setting using a Microcontroller (20.5 kb)  
CC22/01 Computer-controlled Fiddle Yard project (43.2 kb)  
CC23/01 What you need to know to use the PIC Microprocessor (18.1 kb)  
CC23/02 Programming a PIC Microprocessor (34.5 kb)  
CC24/01 Computers and Model Railways - an Overview (28.9 kb)  
DCC01/01 Getting into DCC - a review of several commercial systems (20.2 kb)  
DCC02/01 Introduction to NMRA Digital Command Control (28.5 kb)  
DCC02/02 NMRA Decoder Configuration Variables (CVs) for ZTC / Lenz / Digitrax (21.7 kb)  
DCC03/01 Building a DCC decoder for N gauge (32.6 kb)  
DCC04/02 DCC Loco Conversions (54.7 kb)  
DCC11_05 MERG DCC8 Command Station - DEscription and Operation (301.8 kb)  
DCC11/03 MERG DCC handset HS2 (Rev B): Technical description and use (50.6 kb)  
DCC11/11 MERG DCC Accessory System: Overview, & Testing Assembled Kits (74.6 kb)  
DCC11/12 The MERG DCC Accessory Encoder (Version 2B) (148.6 kb)  
DCC11/13 The MERG DCC Pulsed Output Accessory Decoder (Version 2B) (178.3 kb)  
DCC11/14 The MERG DCC Accessory Decoder Version 3B - Steady State outputs. (152.4 kb)  
DCC11/19 Further Uses for the MERG DCC Steady State Accessory Decoder (110.5 kb)  
DCC20-01 The MERG 2nd gen DCC User's Guide (657.7 kb)  
DCC21/04 The MERG 2nd Generation DCC System (1,812.1 kb)  
G01/01 Transistors (44.3 kb)  
G02/01 Relays - updated (21.1 kb)  
G02/03 Latching Relays (and use for vehicle directional lighting) (22.7 kb)  
G03/01 Digital logic (162.7 kb)  
G05/01 Microprocessors and model railways - updated (34.5 kb)  
G06/01 Computer interfacing (Parts 1 & 2) (88.8 kb)  
G07/01 Multiplexing (22.5 kb)  
G08/01 A practical introduction to logic circuits (108.1 kb)  
G09/01 A loco controller using the Sinclair Spectrum with postscript (69.8 kb)  
G10/01 Sound and model railways (34.3 kb)  
G12/01 Diode - FET logic - a new family ? (261.4 kb)  
G13/01 A novel approach to layout wiring diagrams (32.2 kb)  
G14/01 The on-board controller (208.6 kb)  
G15/01 Loco controller using the Centronics interface (75.9 kb)  
G16/51 A Computer-controlled Throttle unit (192.4 kb)  
G16/55 An introduction to Tcc (Train control centre) software (384.1 kb)  
G16/56 Writing scripts for TCC - A tutorial (346.4 kb)  
G16/71 Layout Wiring: a radically new approach (78.4 kb)  
G16/72 Layout wiring Part 2: Assembling PtP and RPC kits: Installation and testing (54.6 kb)  
G16/85 Model Railway Computer Control Centre (MRCCC): Overview (211.6 kb)  
G16/86 Model Railway Computer Control Centre (MRCCC): User Guide (266.3 kb)  
G16/87 Computer Assisted Cab Control (CACC) (243.1 kb)  
G18/01 CARLOS unveiled - Your Control Panel on your PC Screen (159.8 kb)  
G19/01 Notes on the use of Memory Wire (36.8 kb)  
G19/02 Memory Wire for Points Actuation - comparison of 'One Way' and 'Reversing' wire (45.8 kb)  
G20/01 A simple voltage indicator (33.7 kb)  
G22/01 A Memory wire Turnout Operating Unit - MWTOU (79.1 kb)  
G23/01 Constant current driver for Memory wire (22.7 kb)  
G23/02 Adjustable drive circuit for Memory wire (18.7 kb)  
G24/01 Analogue Controllers for a G gauge Garden Railway (85.1 kb)  
G24/02 Train servo amplifier Testing (as used for G24/1) (26.6 kb)  
G25/01 Using the 555 timer (104.8 kb)  
G26/01 A Moving Message Simulator (42.7 kb)  
G27/01 Solid State Overload Protectors (73.5 kb)  
G28/01 Diode Controlled Slow and Stop sections (73.1 kb)  
Layout CablingTOP OF PAGE
LC01/01 Guidance for Cabling Model Railways (202.8 kb)  
LC02/01 Point to Point-Lite (PTP-Lite) (735.2 kb)  
LC02/02 Putting PTP-Lite to Work - External Interfacing (798.1 kb)  
LC02/03 Putting PTP-Lite to Work - System Installation (512.8 kb)  
LC02/04 PTP-Lite – USB and Serial Interface Backplanes (682.5 kb)  
LC02/05 Putting PTP-Lite to Work – RFID Data Transport (445.6 kb)  
PracticalTOP OF PAGE
P01/01 Practical Guide to Crimping and Insulation Displacement Connectors (IDC) (38.7 kb)  
P02/01 Guidance for Building a Typical MERG Electronic Kit (347.8 kb)  
ReferencesTOP OF PAGE
R05/01 Bibliography:'Electrical and Electronics' Series, NMRA Bulletin (US) (32.8 kb)  
R09/01 Model Railway Electronics - Index to Friberg books 1, 3 & 4. (63.1 kb)  
R10/01 Book Index- A Practical Introduction to Surface Mount Devices (33.3 kb)  
SignallingTOP OF PAGE
S01/01 Wiring complex pointwork (68.9 kb)  
S02/01 ENtrance EXit (NX) Route switching (38.3 kb)  
S04/01 NMRA dc 2-rail track circuiting system (with additional notes) (20.6 kb)  
S06/01 Signal Operation and Automatic restoration (30.2 kb)  
S11/01 I.R.I.S. - Independant Remotely Interlocked Section (128.8 kb)  
S12/01 Four Aspect Signals - Multiplex operation over 1 or 2 wires (53.8 kb)  
S13/01 The ENtrance EXit (NX) Panel - Prototype information (23.2 kb)  
S14/01 Simple Colour Lights signals for two sections (uses reed switch detection) (23.5 kb)  
S15/01 A Noise Resistant Bistable - includes use for reed switch operated 2-aspect signal (16.2 kb)  
S16/01 2-wire control for 4-aspect signals (20.0 kb)  
S17/01 A Damped Motor for 2mm scale Semaphore Signals (33.2 kb)  
S18/01 Electrical Interlocking of Points and Signals (45.7 kb)  
S19/01 The SD2 Signal Driver (50.3 kb)  
S19/02 Basic Principles of Using the SD2 Signal Driver Kit (DC or DCC) (99.5 kb)  
T01/01 Some new ac motors and thoughts thereon (63.7 kb)  
T02/01 A fixed height pulse controller (24.3 kb)  
T03/01 MERG MILLION controller (16.4 kb)  
T04/01 The Walshaw variant of the MERG MILLION controller (27.9 kb)  
T05/01 Motor control (17.4 kb)  
T06/01 Closed loop motor control (91.3 kb)  
T07/01 CMOS in model railway electronics (100.8 kb)  
T08/01 Traction supply (draft only) (26.9 kb)  
T12/01 An integrated controller using the LM317 (51.1 kb)  
T14/01 Controlling dc permanent-magnet motors used in model locomotives (18.6 kb)  
T15/01 A simple overload trip - theory (30.4 kb)  
T15/02 A simple overload trip - construction (498.6 kb)  
T16/01 A Linear controller with overload protection (32.5 kb)  
T17/01 A single knob controller (46.2 kb)  
T18/01 Wired and cordless controllers using joysticks (115.2 kb)  
T19/01 A hybrid pulse-width modulated (PWM) controller (100.4 kb)  
T20/01 Diesels with "real engines" using a free motor (39.6 kb)  
T23/01 A Computer-compatible Pulse Controller (97.5 kb)  
T24/01 DC Motor Control by Negative Resistance (64.7 kb)  
T25/01 The Ultimate Track Circuit Detector ? (76.2 kb)  
T26/01 Single Knob Walkaround Control (94.8 kb)  
T27/01 A Pulsed Linear Controller (40.3 kb)  
T27/02 A Timed-reset Current Trip (28.4 kb)  
T28/01 Track-based Cab Control (162.3 kb)  
T31/01 A Fixed Width Pulse Controller (FWP) (102.0 kb)  
T32/01 Reversed Linked Section Control (RLSC) (128.6 kb)  
Automatic Train ControlTOP OF PAGE
ATC01/02 The ATC Shuttle Control System – An Overview (1,029.3 kb)  
ATC02/01 The ATC Shuffle Mode (130.6 kb)  
ATC03/01 Testing and Setting Up a Standard ATC System (2,100.6 kb)  
ATC04/01 Putting the ATC to Work 1 – Planning Your Configuration (498.8 kb)  
ATC05/01 Putting the ATC to Work 2 – Creating PIC Sequences (293.1 kb)  
ATC06/01 Putting the ATC to Work 3 – Using the Excel Configuration Spreadsheet (440.7 kb)  
CBUS-00 CBUS - A universal layout control system. (262.2 kb)  
CBUS-01 CANACC8 - 15Vac CBUS Module for driving LEDs, Lights and Relays (579.5 kb)  
CBUS-02 CANACC4 - 15Vac CBUS Module for driving Solenoid Point Motors (676.4 kb)  
CBUS-10 Planning for CBUS on your Layout (476.4 kb)  
CBUS-12 CANSOL – 12Vdc CBUS Module for driving Solenoid Point Motors (959.5 kb)  
CBUS-13 CANPAN - 12Vdc CBUS Module for driving Control Panels (1,206.5 kb)  
CBUS-14 CANMIO (10.3 kb)  
CBUS-15 CANPiWI - CBUS WiFi Interface Module (78.1 kb)  
CBUS-17 CANGIZMO – CBUS Module Bench Tester (2,573.5 kb)  
CBUS-20/11 CANVOUT - 12V DC CBUS Module with 8 outputs and 8 inputs (2,374.3 kb)  
CBUS-20/14 CANV4BIP - 12V DC CBUS Module with 4 motorised point drivers and 8 inputs (2,692.9 kb)  
G32/03 CANACC5 - CBUS module for motorised point drivers etc. (313.1 kb)  
G32/04 CANACE3 - CBUS module for Control Panels (100.5 kb)  
G32/05 CAN-RS - An interface module between CBUS and Serial RS-232 (220.1 kb)  
G32/06 CANACE8C - CBUS 8 input combination module (161.2 kb)  
G32/07 CANLED - CBUS module for driving 64 LEDs (107.5 kb)  
G32/08 CANSERVO8 CBUS module for driving R/C Servos (50.7 kb)  
G32/11 Using the CBUS Experimenter’s Kit, Kit 90 (147.4 kb)  
Train DetectionTOP OF PAGE
A07/04 Hall effect switch as Train-on-Track Indicator (22.9 kb)  
S03/01 MERG Train On Track Indicator (ToTI) (incorporating S10/1) (22.2 kb)  
S07/01 Locomotive Isolated Detector (60.1 kb)  
S08/01 Train Detection - report on meeting (talk and discussion) (16.9 kb)  
S09/01 Transducers - or where is it? (45.0 kb)  
T09/01 2-rail track circuits (48.5 kb)  
T09/02 HYPOTRAC - a 2-rail circuit (113.7 kb)  
T21/01 Train-on-track indicator by comparator (45.8 kb)  
T21/02 Train-on-track indicator by comparator (Assembly & Test Instructions) (61.4 kb)  
T21/04 Dual Power Supply Module (143.0 kb)  
T21/05 Train-on-track indicator by comparator: version 3 (218.3 kb)  
T21/06 ToTI-2 – A 2 channel Train on Track Indicator by comparator: Version 4. (1,255.3 kb)  
T22/01 Train-on-Track Indication using Reed or Hall Effect switches (124.2 kb)  
T29/01 Train on track indication using a Flip Flop (15.8 kb)  
T30/01 Yet another Train on track indication (YaToTi) (25.6 kb)  
TD01/01 Dual Hector User manual (4,380.5 kb)  
CC01/01 ZERO-1 Command link (84.0 kb)  
CC01/02 ZERO-1 Slave controller unit - including modification for double heading (61.8 kb)  
CC01/03 ZERO-1 Slave controller (operation & modifications) (58.8 kb)  
CC01/05 ZERO-1 Display console & module (MicroMimic/Phase 3) (36.8 kb)  
CC01/06 ZERO-1 Point accessory module amplifier (19.3 kb)  
CC01/07 ZERO-1 MicroMimic console - battery & inspection (17.6 kb)  
CC01/08 ZERO-1 Loco module - a quick look (32.0 kb)  
CC01/09 ZERO-1 MicroMimic Display System (Mfrs. brochure plus comments) (637.5 kb)  
CC01/10 ZERO-1 Loco module coding chart (22.0 kb)  
CC01/12 ZERO-1 Master Controller Replacement Keyboard (Kit instructions) (25.0 kb)  
CC01/14 ZERO-1 Accessory Module R956 (Technical description and schematic) PB003 (48.0 kb)  
CC01/15 ZERO-1 Slave Cable Buffer (Slave connections at over 2 metres) PB001 (32.9 kb)  
CC01/17 ZERO-1 Modification of AC locos for Zero-1 operation PB002 (26.0 kb)  
CC01/18 ZERO-1 Loco module current booster PB004 (NB. 1.17 and 1.18 will be supplied printed back to back for the single TB price). (25.1 kb)  
CC01/20 ZERO-1 Stabilised Power Booster PB005 (23.0 kb)  
CC01/22 ZERO-1 Accessory Module Extender (22.5 kb)  
CC01/23 Coding ZTC Loco Modules using ZERO-1 Controllers (Hornby and H&M) (54.5 kb)  
G16/00 Remote Panel Control(RPC) System - Progress Report No. 1 (40.1 kb)  
G16/01 Remote Panel Control(RPC) System - Progress Report No. 2 (44.3 kb)  
G16/02 RPC System - Index to bulletins G16/3 - G16/24 (29.0 kb)  
G16/03 RPC System - System Overview (214.5 kb)  
G16/04 RPC System - Interface Specification (85.4 kb)  
G16/05 RPC System - RPI Remote Panel Interface (98.4 kb)  
G16/06 RPC System - DPR Module (8 Relay switching) (319.4 kb)  
G16/07 RPC System - SR04 Module (32 bit O/C Digital O/P) (185.6 kb)  
G16/08 RPC System - FTC Floating Track Circuit Module (8 track circuits) (556.1 kb)  
G16/12 RPC System - RTC Train Speed Controller (260.4 kb)  
G16/13 RPC System - PMD1 Solenoid Point Motor Driver (see G16/26 for On-board DPDT relay module) (86.1 kb)  
G16/14 RPC System - PMD2 Slow-action Point Motor Driver (152.0 kb)  
G16/15 RPC System - PMS2 Slow-action Point Motor Slave (95.6 kb)  
G16/16 RPC System - SD4 Multi-aspect Colour Light Signal Driver (105.5 kb)  
G16/17 RPC System - QPR Quad pole relay board (80.5 kb)  
G16/18 RPC System - RSA RS232/RS485 Adaptor (191.9 kb)  
G16/19 RPC System - SRI4 32 bit shift register logic input module (96.6 kb)  
G16/21 RPC System - Alternative Uses (non-computer applications) (109.8 kb)  
G16/22 RPC System - Serial/Shift register techniques (A general description but with special reference to the RPC system) (158.7 kb)  
G16/23 RPC System - PTP Point to Point data transfer (165.0 kb)  
G16/24 RPC System - RSE Remote Stack Extension system - to extend any RPC module stack (248.5 kb)  
G16/25 RPC System - RDD Remote Data Display (175.5 kb)  
G16/26 RPC System - PMR1 Solenoid Point Motor/Relay driver with on board relay. (83.7 kb)  
G16/27 RS232 - RS485 Buffer (90.9 kb)  
G16/75 Implementing a RPC System on a Home Layout (493.4 kb)  
G16/81 RPC Application on 'Horton' (792.2 kb)  
G16/xx RPC System - The Nottingham Exhibition report (RPC's first public outing) (48.6 kb)  
T33/01 The SuperBloc Concept and the BC3 Controller (78.6 kb)  
T33/02 Block Control Philosophy (94.9 kb)  
T33/11 SuperBloc BC3 Technical Description and Schematics (135.0 kb)  
T33/12 Testing a superBloc BC3 controller (38.9 kb)  
T33/13 SuperBloc Power Supplies (77.1 kb)  
T33/14 SuperBloc Control of Turnouts/Points/Switches (62.0 kb)  
T33/15 How to create a Macroblock 'Cookbook' for SuperBloc design. (143.9 kb)  
T33/16 A Single Track End-to-End Layout for SuperBloc (85.7 kb)  
T33/17 SuperBloc Control of a Fixed Twin Track Layout (75.3 kb)  
T33/18 SuperBloc Controls for a Modular Layout (71.8 kb)  
T33/19 A superBloc Starter Layout (65.3 kb)  
T33/20 SuperBloc Control of Signals (65.5 kb)  
T33/21 PD3 Dual Solenoid Point Motor Driver with SuperBloc Logic Options (166.8 kb)  
T33/22 Using the SD2 signal driver with superBloc (65.3 kb)  
T33/23 Simple Signal Drivers for superBloc (32.2 kb)  
T33/24 PD3 Boost Converter for superBloc (97.9 kb)  
T33/25 A low cost Optical Detector and trains longer than a block (126.9 kb)  
T33/26 An automatic Point Lock for superBloc (75.6 kb)  
T33/27 SuperBloc Hints and Tips (82.6 kb)  
T33/28 Station Stop Timers for superBloc (80.3 kb)  
Electronic TechniquesTOP OF PAGE
ETEC-01 USB to Parallel Bus Interface (MERG-USB) (322.0 kb)  
TEST-01 Using the Layout Control Bus (LCB) Experimenter's Kit (490) (805.2 kb)  
TEST-01 Using the Layout Control Bus (LCB) Experimenter’s Kit (490) (805.2 kb)  

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  • MERG Technical Bulletins are circulated or supplied for personal or club use only. Commercial exploitation, re-publication, or re-copying is NOT PERMITTED without the written consent of the Model Electronic Railway Group, and, where practicable, the author.
  • The use or misuse for the sale, design, supply, process, installation, delivery, test, repair, servicing, and alteration of the designs, instructions, computer code, photographs, circuits, and any other information that appear on this web site is entirely at the risk of the user or visitor to the web site. The information is made available in good faith without warranty of any kind strictly on the basis that no liability will attach to the Model Electronic Railway Group (MERG), its officers and members.