Tektronix 570, Manual

Page: 37 / 134

SECTION 4
MAINTENANCE
PREVENTIVE MAINTENANCE
Air Filter
Care must be taken to assure free vent­
ilation of the Type 570 inasmuch as some of
the components are operated at dissipation
levels such that excessive interior temper­
atures will result without adequate air cir­
c ulation. To assure free passage of air the
i nstrument must be placed so that the air
intake is not blocked and the filter must be
kept clean.
Moreover . the side panels and
bottom cover must be in place for proper
a i r circulation.
Do
not remove the covers
except during maintenance.
A washable EZ KLEEN filter is used at the
a i r intake part of the instrument. Under
normal operating conditions the filter should
b e inspected and cleaned if necessary every
three to four months. More frequent inspection
is required when the operating conditions are
more severe.
The following cleaning instructions are issued
by the filter manufacturer:
( 1 )
If
grease or dirt load is light , remove
filter from installation and rap gently on hard
s urface to remove loose dirt. Flush remain­
ing dirt or grease out of filter with a stream
of hot water or steam.
(2)
If
load is too heavy for treatment described
in ( 1 ) , prepare mild soap or detergent sol�tion
in pan or sink deep enough to cover hlter
when laid flat. Agitate filter up and down in
s olution until grease or dirt is loosened and
floated off.
( 3) Rinse filter and let dry.
(4) Dip or spray filter with fresh Filter
Coat o r Handi Coater.
These products are
a vail able from the local representative of the
Research Products Corporation and from most
air conditioner suppliers.
Fan Motor
The fan motor bearings should be lubricated
e very three or four months with a few drops
o f light machine oil. F ailure to lubricate the
b earings periodically will cause the fan to
s low down or stoP . thereby causing the instru­
m ent to overheat.
Visual I nspection
You should visually inspect the entireosciUo­
s cope every few months for possible circuit
defects. These defects may include such things
as loose or broken connections , damaged banana
jacks . improperly seated tubes , scorched wires
or resistors or broken terminal strips. For
most visual 'troubles the remedy is apparent;
howeve r , particular care must be taken when
heat- damaged components are detected. Over­
h e ating of parts is often the result of other ,
less apparent , defects i n the circuit. It is
es sential that you determine the cause of
overheating before replacing heat- damaged
parts in order to prevent further damage.
Soldering a n d Ceramic Strips
Many of the components in your Tektronix
instruments are mounted on ceramic terminal
strips. The notches in these strips are lined
with a silver alloy. Repeated use of excessive
heat or use of ordinary tin- lead solder will
brea
k
the silver-to-ceramic bond. Occasional
u s e of tin-lead solder will not break the bond
if excessive heat is not applied.
If
you are responsible for the maintenance
of a large number of Tektronix instrument s ,
o r i f you contemplate frequent part change s ,
we recommend that you keep on hand a stock
of solder containing about 3% silver. This
type of solder is used frequently in printed
ci rcuitry and should be readily available from
radio-supply houses.
If
you prefe r , you can
order the solder directly from Tektronix in
one pound rolls.
Order by Tektronix part
number 25 1 - 5 1 4 .
Because o f the shape o f the terminals o n the
ceramic strips it is advisable to use a wedge­
shaped tip on your soldering iron when you
AA
M aintenance - Type 570
4 - 1