Circuit-Protection Part; Unleaded Solder - Sony BCU-100 Maintenance Manual

1-6. Circuit-Protection Part

This unit is equipped with the positive characteristics
thermister (s) (power thermister) as the circuit protection
element. The positive characteristics thermister limits the
electric current flowing through the circuit as the internal
resistance increases when an excessive current flows or
when the ambient temperature increases.
If the positive characteristics thermister works, turn off the
main power of the unit and inspect the internal circuit of
this unit. After the cause of the trouble is re-moved, turn on
the main power back again. The unit works normally.
It takes about one minute to cool down the positive charac-
teristics thermister after the main power is turned off.
Board Ref. No. Address
BE-28 TH4101 B-1 (B side)
TH4201 B-3 (B side)
TH6001 A-6 (B side)
TH6002 A-6 (B side)
TH6003 A-6 (B side)
RE-255 THP1 A-2 (A side)
THP2 A-2 (A side)
VIF-40 PT101 E-1 (A side)
(BKCU-VD1)
Fuse/IC link
w
The fuse and IC link are critical parts to safe operation.
Replace this component with SONY parts whose part
numbers appear in this manual published by SONY.
If not, this may cause a fire or electric shock. Be sure to
use specified component in this manual.
BCU-100 MM
This unit has the fuse and the IC link.
They will blow when abnormality occurs and an overcur-
rent flows in this equipment.
Be sure to replace with the specified parts as shown below
after removing the foreign substances that may cause the
shorts.
Board
BE-28
Part No.
! 1-802-243-11
! 1-802-108-11
MEM-122
(BKCU-EX1)
! 1-804-458-21
MEM-126
(BKCU-EX1)
VIF-40
(BKCU-VD1)

1-7. Unleaded Solder

Boards requiring use of unleaded solder are printed with a
lead free mark (LF) indicating the solder contains no lead.
(Caution: Some printed circuit boards may not come
printed with the lead free mark due to their particular size.)
m
. Be sure to use the unleaded solder for the printed circuit
board printed with the lead free mark.
. The unleaded solder melts at a temperature about 40 dC
higher than the ordinary solder, therefore, it is recom-
mended to use the soldering iron having a temperature
regulator.
. The ordinary soldering iron can be used but the iron tip
has to be applied to the solder joint for a slightly longer
time. The printed pattern (copper foil) may peel away if
the heated tip is applied for too long, so be careful.
Ref. No. Address
F7200 A-5 (A side)
F7700 F-2 (A side)
F7701 F-1 (A side)
F7702 F-3 (A side)
F7703 F-3 (A side)
F7800 A-6 (A side)
F7801 A-6 (A side)
F7802 A-6 (A side)
F7804 A-5 (A side)
F7806 A-5 (A side)
F7807 A-6 (A side)
F7808 A-6 (A side)
F8001 A-5 (A side)
F10 A-4 (A side)
F400 C-3 (A side)
F10 A-4 (A side)
PS1 C-2 (A side)
: LEAD FREE MARK
Part No./Name
!1-576-700-21
Fuse-links 10A, 72V
!1-533-627-21
Fuse (SMD) 5A, 125V
!1-533-627-21
Fuse (SMD) 5A, 125V
!1-533-282-21
IC link 2A, 72V
1-11 (E)