18
th
August 1999
Valhalla Service Manual
Page7
Copyright © 1999 Linn Products Limited. All rights reserved.
Switch on & LED Problems
Important – Do not carry out any work on or near the Valhalla while it is powered up before reading
the ‘
It is assumed at this point that you have checked that the Valhalla is definitely the cause of the fault – not a
bad connection etc, the motor or anything on the LP12. If you have not, please do so before proceeding.
Please note
– It is very important to differentiate between “powering up” and “switching on” the Valhalla. We
define “powering up” as connecting the unit to the mains (this powers up the Valhalla). “Switching on”, on the
other hand comprises of pressing the switch on the turntable to start the platter turning. In this section, we
are referring only to the switching on. If the unit will not power up, this is dealt with in the ‘Power Up
Problems’ section above.)
If you are unsure whether or not the Valhalla is powered up
: If the turntable will not switch on, it can be
difficult to know if the Valhalla is powered up or not. There is one simple, but rather crude & unscientific way
to check: With the Valhalla fitted in the LP12, plug the Valhalla/LP12 into the mains and leave it connected
for about 10 minutes;
unplug from the mains, leave for about 10-20 seconds
and then very carefully (they
may be very hot) touch the resistors R2 & R3 on the Valhalla (the 2 large red resistors beside the terminal
blocks). They should be hot. If they are not, the Valhalla is not powering up.
Switching & LED problems
Symptom
Circumstances
Possible Cause(s)
Cure
Will not switch on
Unit not powered up - See
‘Power up problems’ section
above.
See ‘Power up problems’ section
above.
Will not switch on
Unit powers up
okay but won’t
switch turntable
Bad connection to/from
Valhalla or wires wrongly
connected.
Check all connections between
Valhalla, mains & LP12 – see the
LP12 Circuitry Installation
Procedure for instructions on
correct fitting etc.
Will not switch on
Unit powers up
okay but won’t
switch turntable
Turntable switch faulty. Try
another switch in the
turntable if you have one, or
if you can get access to
another LP12 configured for
Valhalla, try swapping the
boards and/or switches to
ascertain which is faulty.
Repair and/or replace switch –
Linn part no: SWITCH (you
would be forgiven for thinking that
this is a typing error etc, but be
assured this is the correct part
number)
Will not switch on
Unit powers up
okay but won’t
switch turntable
IC4 (switching IC) faulty.
Replace IC4 – Linn part no:
IC 021
Switch LED dies
intermittently
Unit functions okay
otherwise.
Leg of switch LED has a
solder problem – probably
dry solder joint, but perhaps
a solder splash.
Solder fault should be visible –
check & repair solder fault.
Switch LED dead
Constant
Unit functions okay
otherwise
LED faulty.
Replace LED – Linn part no:
MISS 052
