Page 1
LK2 Service Manual
Page2 Copyright Β© 2000 Linn Products Limited. All rights reserved.
ContentsPaul O'NeillIntroduction
About the LK2 SeriesThere were three versions of the LK2:
Β· The first version was known at the time simply as the LK2. It gave an output of 60 watts per
channel (into 8 ohm load) and used PCAS 003 type boards. For the purposes of this manual, we will
refer to this version as the LK260.
Β· The second type was also usually known as the LK2 but was often called the LK275 to differentiate it
from the 60-watt version, as it gave 75 watts per channel. Also used PCAS 003 type boards but with
several improvements over the 60 watt version - the most obvious being the increased power output, but
also had improved protection circuitry and better sound.
Β· The third and last type was known universally as the LK280. 80 watts per channel - used PCAS 020
boards. PCAS 020s, at first glance are similar to PCAS 003s, in that they are roughly the same size,
shape and layout, but they are a completely different design of board (i.e. not just a modified version of
PCAS 003) as a closer examination shows. The LK280 sounded considerably better than either of its
predecessors.
How to differentiate between types of LK2There are several methods of determining the specification of an LK2:
Β· Looking at the serial number of a unit and using the LK2 Product History (accessible via Linfo
website - Product Information) will tell you which revision it was sold as. Since, however upgrade kits
were sold by Linn in large quantities to allow customers to convert their early version LK2 into the latest
spec, many units are not what they seem. The following information will help you to determine the
specification of a unit if its exact history is unknown.
Β· LK280s had LK280 printed on the facia - earlier units (LK2 & LK275) had LK2 printed there, but
beware - an earlier version may have been upgraded to LK280 spec.
Β· LK260s and LK275s had a red power LED and LK280s had a green LED. This is handy as a quick
and easy indicator but is not 100% reliable (LEDs are easily changed)
Β· The best way to determine a units spec is simply to remove the sleeve and look at the boards that
are fitted (see below).
Distinguishing Features of Different Board TypesPCAS 020 - usedin LK280Small heatsink barwith transistors fitted
to it - found on PCAS
020 onlyCapacitor &resistor (bridged)
not fitted to 60watt boardThese diodes andcapacitors not fitted
to 60 watt boardsPCAS 003 - usedin LK260/LK27560 watt type used same boardbut with some differences, asshown belowSmall Hybrid boardfitted here at 90 degrees
to main board - found on
PCAS 020 only
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LK2 Service Manual
Page3 Copyright Β© 2000 Linn Products Limited. All rights reserved.
ContentsPaul O'NeillAbout this manualThis manual deals effectively with three quite distinct amplifiers. The amps have enough in common to justify
this approach and this avoids the confusion that might come with separate manuals. Any differences
between the types will be dealt with in the Circumstances column - e.g. Applies to LK280 only.
This manual is designed to help you, as a Linn Retailer or Distributor, to repair as many LK2 faults at your
repair centre as is practical and so provide the best possible service for your customer should a problem
arise.
If you have any suggestions or comments regarding this manual, please contact Paul ONeill at Linn
Products Ltd: By E-mailPAULO@LINN.CO.UK
By Phone++44 (0) 141 303 5005
By Fax++44 (0) 141 644 4262 Marked for attention of Paul ONeill
Retailer & Distributor ObligationsLinn Specialist Retailers or Distributors are obliged to carry out the repairs in this manual under the terms of
the contract & warranty agreements. You should return a faulty product to Linn for repair, only if the fault is
not covered in this Service Manual. If a product, which is under warranty, is returned to Linn for repair and
the fault is covered in the service manual, Linn may levy a charge and this charge should not be passed to
the customer.
Spare Parts Availability and LK2 repairPlease note that the LK2 has been discontinued for some considerable time now and as such, we cannot
guarantee the supply of spare parts - many are simply no longer available and some others are no longer in
stock. Some part numbers are listed throughout this manual, but these are provided for information only and
this does not imply that these parts will be available should you request them.
Linn guarantee that we will support a product until 5 years after the final build. We take this obligation very
seriously and also go much further. Beyond this date, we will repair any Linn product that we possibly can,
where it is within our power to do so. However, due to the difficulty with the availability of spare parts, as
explained above, it is occasionally not possible to repair a product or supply parts for repair, if the necessary
parts are not available.
How to use this manualThe main body of this manual, the fault table, is designed to be as quick and simple as possible to use when
you are confronted with a faulty product and so it is arranged by fault symptom as the symptom is usually all
that you will know about the fault.
Also read the LK2 fault finding - Hints & Tips section below as the information contained there may save
you a lot of time.
If you are unsure about the meaning of any words or phrases, look in the Glossary. (accessible via Linfo
Website - Product Information)
Before embarking on any Service work, you should read the Service Procedures section (accessible via
Linfo Website - Product Information), as there are certain procedures that must be followed in order to
ensure the problem is resolved quickly and permanently
Table of contents & fault symptoms
Look firstly at the table of contents and find the category that covers the symptom you are seeing, then look
down the list of faults in that section until you find the symptom or symptoms that best describe the problem.
Circumstances
Then simply follow the table along - the table specifies circumstances surrounding the fault symptom - e.g.
whether the fault is likely to be intermittent or constant, if the fault only occurs within a range of serial
numbers etc.
Possible causes
The next column details possible causes - this is effectively the most important section, probably the main
reason you are looking at this manual at all. There may be several possible causes for the symptom you
have - it is worth checking out all of these (and bear in mind that there may be more than one fault). For
