RCA SSB-1, Инструкция

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Set the TRANSMITTER GAIN for a full
output on the channel with the lowest re­
sponse. (This is the channel where the
TRANSMITTER GAIN control must be most
advanced for full output.) Keeping the oscil­
loscope coupled to the antenna, set the level
on the oscilloscope for 20 divisions at full out­
put. Set the TRANSMITTER GAIN at mini­
mum. Throw the CARRIER switch to IN and
adjust capacitor C240 for 10 divisions on os­
cilloscope. Raise the TRANSMITTER GAIN
control until the PEAK MODULATION INDI­
CATOR lights. Pattern on oscilloscope should
appear as a two-tone signal with a sharp
cross-over point as illustrated in the figure
below.
5. R E P L A C E M E N T A N D T U N I NG
O F M E C H A N I C A L F I L T E R S .
a_.
FILTER TYPES- Three slightly differ­
ent variations of mechanical filters, FL201
and FL202, have been supplied. All of these
pass an upper sideband approximately 3 kc
wide while rejecting the 250 kc carrier. Be-
cause of the variations, however, certain dif­
ferent accessory components are used with
each of the three type filters. These compo­
nents are li sted in Table 4 and shown in the
schematics and Parts List.
Q..
REPLACEMENT- Although the mech­
anical filters FL201 and FL202 are designed
for continuous duty over long periods of time
without maintenance, it may become neces­
sary to replace one because of failure due to
overloading, burn-out or physical damage .
Direct replacement of one filter by another
of the same type will require no special pro­
cedure except that, irr equiprnents Serial
Numbers 5601 and above, the new filter will
require tuning in accordance with paragraph
c. below. In case the filter to be installed is
of a different type than the one in the equip­
ment, proceed as follows:
(1) FOR EQUIPMENTS SERIAL NOS.
5501 TO 55250.
Type F-250Z-4 filters whether
modified or not, may be used. No filter tun­
ing is provided. Type MFU -250-1 filters can
not be installed in these equipments.
(2) FOR EQUIPMENTS SERIAL NOS.
5601 TO 56200.
These equipments are supplied
with T ype F-250Z-4 filters at the factory. Di­
rect replacement by a modified F-250Z-4 (as
supplied for spares on Serial Nos. 5501 to
55250) is satisfactory and the new filter should
then be tuned in accordance with paragraphg_.
TABLE 4. COMPONENTS USED WITH FILTERS
CAPACITORS
RESISTORS
EQUIPMENT
MECHANICAL C312
BRACKET
SERIAL
FILTER C313 C238 C242
R285 A201
NUMBERS FL201
C314 C294 C293 R255
R286 (4 req'd)
FL202
C315
5501 Type
to F250Z-4
Not C242-82uuf Not
Not Not
55250 (modified)
Used 91uuf C293-91uuf Used
Used Used
5601
to
Type
Not
Not Radiomarine
56200
F250Z-4 7-45uuf 68uuf
62uuf Used
Used A-1214592
56201
and
Type 20 to
33K, 47K,
Radiomarine
above
MFU-250-1 125uuf 360uuf 360uuf
1/2W 1/2W A-1214593
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