Saturday, 12 July 2025

Technics SL-DL1 1980's Linear Legend Turntable Recap



Technics SL-DL1 1980's Linear Legend Turntable Recap. Vintage precision meets timeless sound.

The original electrolytic capacitors listed in the Technics SL-DL1 service manual are no longer available. Suitable modern replacements have been selected based on equivalent capacitance, voltage ratings, physical size, and performance characteristics. Recommended replacements include high-quality audio-grade capacitors such as Panasonic FM, Nichicon ES (Muse) bipolar, Nichicon FG, and Elna Silmic II. Some substitutions were made due to specific voltage and space constraints.
 
Technics SL-DL1 service manual original list of electrolytic caps
    Cap Part Number                          Voltage                     Capacitance
        C3     ECE-B1VS102                                     35V 1000µF
        C4             ECE-B1CS102 16V 1000µF
        C5     ECE-A1VS330 25V 33µF
        C6     ECE-A1ES470 25V 47µF
        C7     ECE-A0JS471 6.3V 470µF
        C101     ECE-A1AS101 10V 100µF
        C102     ECE-A1ES101 25V 100µF
        C104     ECE-A1AS470 10V 47µF
        C107     ECE-A1AS470 10V 47µF
        C111     ECE-A25Z4R7 50V 4.7µF
        C114     ECE-A1CN101S/B 16V 100µF NON-POLAR
        C115     ECE-A1CN101S/B 16V 100µF NON-POLAR
        C301     ECE-A1CS330 16V 33µF
        C305     ECE-A16Z33 16V 33µF
        C308     ECE-A50Z1 50V 1µF
        C309     ECE-A1CS330 16V 33µF
        C319     ECE-A1ES101 / ECE-A0JS471 25V / 6.3V 100µF / 470µF
        C401     ECQ-E2A473MZ0 450V 0.047µF Polyester Film



My list from HiFi Collective . (Selection depends on matching original voltage(or higher) and capacitance ratings.)


Each bag was labeled with the capacitor value and number, and as capacitors were replaced, the old ones were placed in their corresponding bags for easy reference or troubleshooting later.



For ease and to avoid straining wires, it’s best to remove the entire board. Before removing the PCB from the turntable, feed a cable tie through the existing holes near connector CN101 —this provides a grip to safely separate the fragile phenolic PCB from the direct drive PCB without damage.




It’s good practice to mark all capacitor numbers on the silkscreen with a red marker before starting, clearly indicating which ones to remove. The capacitor polarities are also shown on the silkscreen.



Since axial capacitors weren’t available, I bent the leads downward and drilled a new hole for the positive lead to fit the capacitor properly, with a dap of hot glue.


Brass standoffs were used in all PCB mount holes to protect tall components from damage when the PCB is flipped.



The fully recapped board




Regarding the Technics SL-DL1 Disc Detection Logic:

This explanation assumes you are familiar with the turntable’s disc detection shutter mechanism in the lid.

If you’re troubleshooting disc detection issues like I was, understanding the underlying logic can be very helpful.

The phototransistors (SVTPH101 NPN Darlington) are located in the lid, while the light source LEDs are positioned beneath the platter, shining through the mat holes. These components can be tested in strong ambient light or by using a torch. By holding the lid switch while the lid is open, the tonearm will activate and move toward the "read disc" position — even when no disc is present.

Be aware that the lid logic can be misleading. Once the disc shutter position is detected, the tonearm will always move to the last recorded shutter position, regardless of any issues or the auto mode, until the lid switch is reset by releasing it.

Also, the momentary lid switch is not a simple on/off switch; it has six pins and features both normally open and normally closed contacts.