Linn LK260, Service Manual

Page: 16 / 35

LK2 Service Manual
Page16
Copyright © 2000 Linn Products Limited. All rights reserved.
Contents
Paul O'Neill
Tripping Applies only to
LK280
Probably constant
Power transistor (the large
transistors clamped to the
heatsink) faulty.
It is sometimes possible to
measure these transistors
using an ohmmeter to check
if faulty (usually internal
short-circuit across one or
more of the junctions), but
also there is the possibility
that the transistor measures
okay but is indeed faulty.
It will sometimes be
necessary to change them to
confirm or rule out this fault. Check / replace power
transistor(s).
Part details –
Q23 & Q30 – 2SA1386; PNP;
160V; 15A; MT100 (Linn part no:
TRAN 017)
Q24 & Q34 – 2SC3519; NPN;
160V; 15A; MT100 (Linn part no:
TRAN 018)
Tripping Applies only to
LK275 & later
versions of LK260.
Probably constant
Power transistor (the large
transistors clamped to the
heatsink) faulty.
It is sometimes possible to
measure these transistors
using an ohmmeter to check
if faulty (usually internal
short-circuit across one or
more of the junctions), but
also there is the possibility
that the transistor measures
okay but is indeed faulty.
It will sometimes be
necessary to change them to
confirm or rule out this fault. Check / replace power
transistor(s).
Part details –
Q20 & Q27 – 2SA1386; PNP;
160V; 15A; TO218 (Linn part no:
TRAN 017)
Q24 & Q31 – 2SC3519; NPN;
160V; 15A; MT100 (Linn part no:
TRAN 018)
Tripping Applies only to
earlier versions of
LK260
Probably constant
Power transistor (the large
transistors clamped to the
heatsink) faulty.
It is sometimes possible to
measure these transistors
using an ohmmeter to check
if faulty (usually internal
short-circuit across one or
more of the junctions), but
also there is the possibility
that the transistor measures
okay but is indeed faulty.
It will sometimes be
necessary to change them to
confirm or rule out this fault. Check / replace power
transistor(s).
Parts may be as listed in the box
above or they may be as listed
below, depending on whether it is
an earlier or later version of
LK260.
Part details –
Q20 & Q27 – TIP36C; PNP;
100V; 25A; TO218 (Linn part no:
TRAN 005)
Q24 & Q31 – TIP35C; NPN;
160V; 15A; TO218 (Linn part no:
TRAN 004)
Tripping May be intermittent Faulty component in circuit. See “ Fault Finding on the LK2 –
hints & tips ” section at the
beginning of this manual.
Distortion / crackling etc
Symptom Circumstances Possible Cause(s) Cure
Output distorted –
may one or both
channels May be intermittent Power-up problem – if amp
receives insufficient power it
will struggle to amplify the
signal and distortion will
occur See Power-up problems section
above.