Philips MX3900D Service Manual page 9

Service positions
Service position C (Supply and Amplifier boards loosen)
Caution:
1) In some of the service positions the Mains supply is
exposed, therefore service technicians have to exercise
care to prevent electric shock.
2) The copper pattern on the Mains board should be cov-
ered with non-conductive insulation during fault-finding
on other parts of the set.
3) Insulation sheet (eg. thick paper or cardboard) should be
use during fault-finding to prevent short-circuiting of
copper patterns to metallic surroundings.
2-3
Note:
The ground connection between AV board stoko pin
1100 and Amplifier board stoko pin 1320 must be con-
nect ed during Service pos C and D in order to have
sound output at the Loudspeakers.
Service position D (Mains & AV boards loosen)
Thick paper
Service position E (5DTC Mechanism, Mono FE and Mono
BE boards loosen)
Thick paper
2-3
Mains Board
with non-
conductive
insulation
attached to the
copper pattern