Linn LK280 - DC at Output; DC Voltage at Output

LK2 Service Manual
Page17 Copyright © 2000 Linn Products Limited. All rights reserved.
Contents Paul O'Neill
Output very badly
distorted
Applies only to
LK260 & LK275
Probably constant
One of the “Reliability
Modification” components
has failed
Carry out “LK2 Reliability
Modifications” – procedure can
be accessed via Linfo – Product
Information.
Distorted output May be intermittent Faulty component in circuit. See “Fault Finding on the LK2 –
hints & tips” section at the
beginning of this manual.
Crackling noise
from output
Probably
intermittent – may
be temperature
dependent
Transistor in circuit faulty –
junction is ‘breaking down’
See “Introduction to Fault
Finding” (accessible via Linfo –
Product Information)
Or
See “Fault Finding on the LK2 –
hints & tips” section at the
beginning of this manual.
DC at output
Symptom Circumstances Possible Cause(s) Cure
DC voltage at
output. Fault
symptoms vary –
levels of voltage
etc.
Probably constant Regulator U1 or U2 faulty Replace faulty regulator – part
details:
U1 – LM317T Voltage regulator
(Linn part no: IC 005)
U2 – LM337T Voltage regulator
(Linn part no: IC 006)
DC at output May be intermittent Faulty component in circuit. See “Fault Finding on the LK2 –
hints & tips” section at the
beginning of this manual.