Tektronix 1L30, Инструкция по эксплуатации

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Fig. 4-2 identifies the polarity of the glass diode types
used in this instrument.
!■' t+ri'
M a in te n a n c e — Type 1L30 r
Removing the Oscillator Assembly
NO TE
Fig. 4-2. Diode polarity for glass diodes.
A com plete oscillator assembly is listed in the T'
M echanical Parts section w ith its sub-parts listed |
under the assembly num ber. W e recommend re- |
placing the com plete assembly because -it is ca li- |i
brated and re ad y to install. If a sub-part (such £■
as a varactor or pick-up p ro b e ) is replaced , a
com plete recalibration o f the oscillator is usually
required b efo re it can be re-in stalled in the unit. f
This calibration requires a d d itio n a l test equipm ent
that is not listed fo r the standard calib ratio n pro- r,;
cedure. See C a lib ra tio n section. f
1. Unsolder the connection to the feedthrough terminal ,'j
at the rear section plate cap of the oscillator and discon­
nect the pin connector to the varactor (Fig. 4-3A). p
Wiring Color Code
The insulated wire used in the Type 1L30 is color-coded
according to the EIA standard color code to facilitate cir­
cuit tracing. The widest color stripe .identifies, the first color
of the code. Power supply voltages can be identified by
the color stripes and the backg&rund color. W hite back­
ground indicates a positive supply. A tan background in­
dicates a negative supply. Table 4-2 shows the wiring color
code for the power supply voltages used in the Type 1L30.
TABLE 4 -2
W irin g C o lor-C o de
Supply Back­
ground
Color
( P o larity)
1st
Stripe
2nd
Stripe
3rd
Stripe
( If- a p ­
p lic a b le )
- 1 0 V Tan Brown Black
-M O V W hite Brown Black
+ 7 5 V W hite Violet Green Black
+ 100V W hite Brown Black Brown
— 150 V Tan
Brown Green Brown
: + 2 2 5 V W hite Red Red. Brown
RF cables for the RF and IF sections are miniature co­
axial cables. Some of these cables have a lossy character­
istic and are identified with a white outside coating. The
standard 50 ohm low-loss coaxial cables have a clear plas­
tic outside coating. Do not interchange the lossy type with
the standard 50 SI type when these coaxial cables are
replaced.
REMOVING A N D REPLACING ASSEMBLIES
W A R N IN G
Disconnect the instrument from the pow er source
b efo re attem pting repair a n d /o r replacem ent o f
any sub-assembly.
Remove these screws
(A) Remove the indicated screws to repair or replace the
oscillator assembly. _______________________
Set screw
Set screw for fo r outer
inner choke choke
I
©
4 -3
Fig. 4-3. Oscillator assembly.