Garrard GT-35 and GT-35P Belt Drive Turntable Servicing Information
This document provides comprehensive servicing information for the Garrard GT-35 and GT-35P belt drive turntables.
General Information
The Garrard GT-35 is a sophisticated belt-driven integrated record changer, also available as a semi-automatic single player. It features a DC servo-controlled motor, electronically regulated for 33 and 45 RPM speeds, with pitch control for ±3% variation. The pickup arm is 'S' shaped with a detachable cast magnesium headshell and a low effective mass. It includes a cue/pause control and a bias compensator. The GT-35 is available with moulded or wood-finish plinths and has DIN and RCA audio output connections.
The GT-35P is the single player version, similar to the GT-35 but with a lower profile dust cover. Its playing facilities, apart from manual control of the pickup arm and playing a stack of records, are the same as the GT-35. Both models are available for different voltage supplies (110/125V AC and 220/240V AC).
Specifications
Motor and Turntable: DC multi-pole servo controlled, Belt drive, 33⅓ and 45 RPM (variable ±3%), 298mm/317mm dia. die-cast aluminium turntable with integral strobe bars.
Pickup Arm: Direct static-balance, 'S' shape aluminium tubular, 230mm effective length, 17mm overhang, 23° 24' offset.
General: Power supply 110/125V AC or 220/240V AC, 50Hz or 60Hz. Power consumption 2.5 watts. Dimensions 450mm x 360mm x 195mm (W x D x H) for GT-35, 450mm x 360mm x 156mm (W x D x H) for GT-35P. Weight 6.5kg (14.40lb) for GT-35, 6.225kg (13.79lb) for GT-35P.
Installation
The installation process involves unpacking the unit, removing support mouldings, fitting the turntable platter and mat, and securing the pickup arm. Detailed steps are provided for unpacking sequence and fitting a cartridge, including alignment and stylus force adjustment.
To Play Records
Instructions are provided for manual play, automatic play, repeat play, interrupting play, and playing a stack of records automatically. The document also explains how to control drive speed and vary pitch using the stroboscope and pitch control knobs.
Service Adjustments
This section details various adjustments required for optimal performance:
- Pickup arm lifting height: Adjusting the height at which the arm lifts at the end of a record.
- Pickup arm lowering position (GT-35 only): Setting the stylus to land correctly on the record.
- Pickup arm return position: Adjusting the arm's return to its rest.
- Cueing lowering rate: Adjusting the speed at which the pickup arm lowers.
- Pickup cartridge angle (horizontal): Ensuring correct cartridge alignment.
- Pickup headshell out of parallelism: Adjusting the headshell for parallelism.
- Pickup arm bearings (horizontal): Checking and ensuring free movement of the arm pivots.
- Pre-set speed control: Adjusting the motor speed for accurate RPM.
- Record support platform position (GT-35 only): Setting the correct position for multi-play records.
- Mechanism drive belt tension: Adjusting the drive belt for optimal performance.
- Release lever setting: Adjusting the release lever for correct operation.
Access to Components
Guidance is provided on how to access internal components for servicing, including disconnecting the power supply and removing the turntable and mat.
Dismantling Main Component Assemblies
Detailed instructions are given for dismantling various assemblies, including the pickup arm, pickup base cover, lifting platform, bias compensator, mechanism module, and PCB assembly.
Modular Mechanism – Function and Operation
This section explains the operation of the modular mechanism, detailing the sequence of movements of levers during automatic play, record changing, and other functions. It also covers the condition of the unit and control operations.
Routine Maintenance
Recommendations for routine maintenance include cleaning the stylus with a camel-hair brush, cleaning the turntable mat, and servicing the drive system annually. Instructions are provided for removing the turntable drive drum.
Fault Diagnosis
The document includes comprehensive fault diagnosis charts and tables for audio problems (no sound, distorted sound, hum) and mechanical problems (pickup arm issues, wow and flutter, rumble). Remedies are provided for each identified fault.
Circuit Diagrams
Circuit diagrams for mains supply connections and strobe electronics are included for detailed technical reference.
