How to service a Linn Lingo (mk1)
By: Ben Zotto
Tags: Repair, How To, Audio, Turntables, Electronics

Linn’s Lingo, the first outboard power supply for the LP12 turntable, was introduced in 1990 and sold in its original form for about a decade. Because of their (relatively!) compact form factor and first-party branding, early Lingos (“version 1” or “mk1”) remain popular on the used market. These power supplies have now reached the age where their electrolytic capacitors can become marginal or dried out, and for optimal operation they should be “serviced.” This consists of a new set of capacitors followed by a voltage check/calibration. I did this to a Lingo recently, and seeing no other comprehensive guides online, I’m writing this one.

Disclaimer: This is a best-effort guide and is not guaranteed to be free of errors. If you discover any, please let me know. Also, during calibration, live voltage including mains voltages is accessible; mains electrocution can injure or kill. Only work with live current if you know how to do so safely.

This is what we’re servicing. If yours looks different, stop now!

Performing this service may correct (or head off) motor-related problems of low torque, no-start, or difficulty getting to speed. This guide won’t fix a power supply that has non-capacitor-related issues; for other concerns, look around for a Lingo service manual or take it to an expert.

Experience required

This is mostly straightforward desoldering and soldering, but given that the market value of a used Lingo still runs to a few hundred dollars, probably not recommended as a first-time project if you’ve never done anything like this before.

Tools

Phillips head and hex screwdrivers, desoldering pump/gun/braid, soldering iron, digital voltmeter. Bonus: bench isolation transformer.

Parts

There are 20 electrolytic capacitors (“caps”) on the Lingo board, and if you’re bothering to do any, you should just replace them all. The three largest caps are axial (leads coming out each end) and all others are radial (both leads coming out one end). Axial style caps have fallen out of fashion and are increasingly difficult to find in some specs. If you can’t source them, you can substitute a radial of the same values — they’re functionally identical — but it will be more fiddly to connect securely.

(3x) 33μF, 350V axial .

. (2x) 2200μF, 25V

(2x) 1μF, 450V

(3x) 220μF, 16V

(2x) 100μF, 63V

(8x) 22μF, 63V

As always, replacement capacitors should match the original capacitance (μF), and must be rated for at least the original voltage — you can replace a capacitor with one that can handle a larger voltage but never the opposite. General use capacitors (including the original Lingo parts) tend to have an upper operating temperature spec of 85°C. If you use higher-temp parts (105°C) you’ll pay a bit more but they’ll likely last longer in warm environments, like the inside of a power supply. You’ll also want to use caps from respected manufacturers: look for Nichicon (the audio cult favorite), Rubycon, Kemet, Vishay/Sprague, Panasonic, Illinois, CDE. A good rule of thumb is that anything you buy from DigiKey or Mouser will be of good quality; and anything that comes in bulk assortment kits off Amazon for cheap should be avoided.

Step 1: Open the case and remove the PCB

With the Lingo unplugged (obviously), flip it upside down and remove the four screws that secure the board sled to the outer case (near the four rubber feet). Once done, you should be able to slide the outer case away from the sled; set that aside.

You can remove the plastic front panel by removing the two screws on the very front of the bottom, and the screw on each upper-side of the panel. Be careful, because the plastic is thin in parts and can crack or break around the screw threading nuts. (You may not need to remove the front panel but I found it useful to understand how to free the switch.)

Remove the power switch assembly from the case front by taking out the two screws that hold it down on the inside. Leave the switch mechanism intact, it can just dangle there away from the sled.

Using a small hex screwdriver, remove the four screws holding the PCB to the sled, and the two that secure the turntable connection socket. There is one final screw that comes in from the underside of the sled into the transformer; remove that as well. You should now be able to lift out the PCB.

Front panel removed, power switch assembly hanging to the side of the case. The six screws holding the PCB down are marked in pink circles. The board’s power plug is indicated with the arrow.

Before or during its removal, unplug the power connection on the board. You can use a flat screwdriver to carefully jimmy it if necessary.

Lift out the board, taking care not to scrape its surface on the case, and set aside the sled. You’re ready to replace the capacitors.

Step 2: Replace the capacitors

For each capacitor, desolder the connection on the underside of the board. I recommend taking photos along the way so you can always refer back to which part came from where and which orientation they were in. You’ll need at least a solder sucker or some facility with desoldering braid to do this well; the ne plus ultra is a good desoldering gun which are wildly expensive but worthy investments.

⚠️ Note that some care is required here; the Lingo board is two-sided, and some of the capacitor legs are soldered to pads that are part of conductive channels back through to the top side of the board. You don’t want to separate or break any of these.