Broadcast Electronics 3000 Series - Module Locations and Adjustment Points; Electronic Adjustments; General

I 1111 O'f IE
WHEN REPLACING MULTI-PIN COMPONENTS (TRANS-
FORMERS, CONNECTORS, ETC.) DESOLDER INDIVID-
UALLY ALL THE PINS BEFORE ATTEMPTING TO REMOVE
THE COMPONENT. IT IS VIRTUALLY IMPOSSIBLE TO
HEAT ALL THE PINS SIMULTANEOUSLY.
Check the mounting holes in the board to be sure they are clear
of solder and open before mounting the replacement. Put the leads through
the holes and trim the leads to about l/8 inch. Bend the leads over so
they touch only the foil strips the leads are to be soldered to.
Touch the iron to the leads and let the solder flow onto the
foil. Always use a fine rosin core solder such as No. 20 gauge. Check for
''bridges'' of solder
between adjacent foil strips.
Clean the flux off the connection with alcohol. Solder flux left
on the printed circuit board may cause noise in the circuit. If the contacts
were covered with masking tape, clean them also with alcohol.
5-4.
MODULE LOCATIONS AND ADJUSTMENT POINTS
The locations of the electronic modules are shown in the assembly
diagrams in
Section VI. Individual electronic parts are listed by boards
in Section VI. The electronic adjustments are accessible through the card
cage cover immediately behind the tape deck.
All adjustments are labeled
for easy reference.
5-5.
ELECTRONIC ADJUSTMENTS
5-6. GENERAL
Before adjusting the electronics, clean the tape head(s) with
BE-903 cleaning fluid or isopropyl alcohol. Be sure the playback (and
record) head is properly aligned. In record models, the playback electronics
should be adjusted before adjusting the record section.
An NAB standardized test and alignment cartridge is required for
proper adjustment of the
unit. The electronics may be adjusted to another
standard (such as
IEC, CCIR) by use of an alignment cartridge recorded to
that standard. In all cases, refer to the manufacturer's instructions
supplied with the cartridge.
I WARINUIIIIG I
BE CERTAIN THE LARGE ELECTROLYTIC CAPACITORS
ON THE POWER SUPPLY BOARD AND THE MOTOR CAPAC-
ITORS ON THE CHASSIS ARE FULLY DISCHARGED BEFORE
ATTEMPTING MAINTENANCE INSIDE THE UNIT.
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