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TTS 26B
Section 3
ACTION
RESULT
o.
To send pulses f r o m the internal oscillator
o p e r a t e the FUNCTION key to SEND OSC.
To
send with the d i a l of a telephone s e t , o r with a
dial connection to the
EXT
DIAL jack o r t e r m i n a l s
r e s t o r e the FUNCTION key to SEND DIAL and
turn the
EXT
DIAL CIRCUIT switch to DIAL
RELAY- B&G. This also applies to a d r y contact
e x t e r n a l s o u r c e connected to the EXT DIAL jack
o r t e r m i n a l s .
If the external s o u r c e supplies wet
contact pulses, the EXT DIAL CIRCUIT switch
should be turned to DIAL RELAY -LOOP. (See
Note 3 ) .
NOTE
2 :
If i t i s d e s i r e d to send ground and battery the SEND o r SEND AND REC switch m u s t be in
the e x t r e m e clockwise position and the D R O P toggle switch m u s t be operated to DROP
-
E =G&B.
NOTE 3:
If
the trunk t e s t is patched through the
LINE
and DROP jacks of the TTS
26B
and the s e t
i s sending on the M lead, the trunk may be made busy toward the d r o p by operating the
DROP (M) key to O F F HOOK Similarly, sending on the E lead the trunk may be made busy
toward the line by operating the LINE ( E ) key to O F F HOOK.
This
is
shown i n schematic
f o r m i n fig. 3 -2.
3 . 1 7 MEASURING
O/o BREAK
O F A RECEIVED SIGNAL. In a l l these m e a s u r e m e n t s i t is important to
----
adjust the
METER
CAL control to take into account the voltage d r o p a c r o s s any r e s i s t a n c e between the
s o u r c e of the signals and
the
measuring set.
T h i s is accomplished while the
METER
CAL control is
being adjusted, by having
a
s h o r t c i r c u i t o r off hook p r e s e n t at the s o u r c e of s i g n a l s . I t also is import-
ant that this adjustment should be made AFTER the receiving mode of the m e a s u r i n g s e t h a s been estab-
lished by the RECEIVE switch
(
o r the
SEND
o r
SEND
AND REG switch if this switch controls the
receiving
as
well a s
the
sending modes).
If another
TTS
26B
is being used a s the s o u r c e of signals, the
off hook may be applied to the trunk by opening i t s
FUNCTION
switch to SEND-OFF HOOK.
3 . 1 8 MEASURING
% BREAK
ON LOOP CIRCUITS.
The following provides the procedure for Measuring
%
B r e a k on Loop Circuits (See fig. 3-3a):
ACTION
RESULT
a.
With no power applied to the s e t , check the
It should be on the 100 line of the
(70
BREAK
position of the m e t e r pointer.
scale ( m e t e r e l e c t r i c a l 0). If it i s off adjust the
s c r e w on the front of the m e t e r c a s e to bring i t
to this line.
b.
After adjustment, back off the adjustment
s c r e w slightly to remove mechanical contact
between the adjustment s c r e w and the m e t e r
mechanism.
c.
FIRST
i n s e r t the 310-type plug of the power
supply patch cord into the 48 VOLT jack of the
s e t observing the proper tip and s l e e v e polarity,
and then connect i t to
the
48-volt d c supply.
This completes the mechanical adjustment of the
m e t e r e l e c t r i c a l 0.
If connection is not made i n this sequence a
battery supply fuse m a y blow.
If
the wrong 48-
volt jack is used diode protectipn within the s e t
will protect the s e t f r o m d a m a g e , but the s e t
will be inoperative in succeeding s t e p s .
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