Our Quad 33 service includes:

Fault diagnosis, replacement of all electrolytic capacitors, out of tolerance components and a full performance test, PAT* and 48 hour soak test**.

Standard 33 full service example

1. Dismantle unit, remove front panel. Clean internally and externally to remove dust and grease and destroy bacteria. If electrically safe to do so, carry out DC and AC analysis. (This means measuring key dc voltages and ac signals around the full circuit to check for anomalies. This is done using, a signal generator, spectrum analyser, oscilloscope (SGSAOS) and multimeter). Note down the anomalies and correct obvious causes immediately. Record the more in depth anomalies, if any and analyse/rectify, after the more pressing issues are corrected. 2. Clean and lubricate, volume and tone control, tracks & wipers, Replace any pots that are excessively noisy. Detach Push-button switch banks from chassis to access and clean/lubricate contacts. Check continuity of all buttons ‘in and out’ position, and note anomalies. Clean push button, slide and stator contacts, with contact cleaner/lubricant. Check and note any remaining switch anomalies. 3. Clean PCB edge contacts and carry out a similar process to the switch banks. Dismantle the slider pot and mechanism and clean and lubricate the tracks/wipers & bearing. Replace the pot if too worn to re-use. Contact owner if PCB edge connectors or push button switch banks are U.S. 4. Check the components on the set of PCB boards (PSU, Tone, Disc. Tape, Front end and motherboards), and replace all OT or faulty components. (This often results in the full set of 21 electrolytic capacitors being replaced, along with all the component causing the previously noted faults/anomalies. eg., semiconductors, foil capacitors and resistors.) 5. Diagnose, rectify any remaining faults, carry out a full Flat, RIAA and tone and filter frequency response/distortion check on both channels (SGSAOS). Set up 33 on soak bench * and carry out a combined listening test with the customers fully serviced power amplifier (PA) or with our in house PA. Leave running for several hours (usually at least 8 - 24 hours), playing source music alternatively, signal generator/dummy load, if looking for specific intermittent faults. 6. If the 8 hour soak test/ listening test is passed, carry out PAT earth bonding and insulation test – and contact customer, job done!

* 'PAT' = Portable Appliance electrical safety Test : ‘U.S.’. = unserviceable ** 'Soak testing' involves monitoring the signal output from all inputs for several hours to locate intermittent or impending faults.

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