HP TM 11-6625-2779-14&P - Manual (Page 10)

Section I Model 3555B
1-5. A noise-to-ground (Ng) function is included
which permits the measurement of longitudinal noise.
When making noise-to ground measurements the
impedance between INPUT terminals is greater than 80
kilohms and is 100 kilohms between each terminal and
ground. A HOLD function permits holding the line while
noise measurements are being made. The input
circuitry provides 40dB of longitudinal noise attenuation
when noise-to-ground measurements are being made.
1-6. A DIAL/BAT function permits connecting a
lineman's handset to the line for the purpose of dialing
and at the same time connects the front panel meter to
the power supply so that the battery voltage or
unregulated power supply voltage can be monitored.
1-7. Jacks accepting Western Electric type 241, 309,
310, 347, and 358 plugs are provided for INPUT
connections to the 3555B. Dual binding posts accept
banana plugs, wires, lugs or phone tips and a pair of
special connectors permit the attachment of clip leads
from a lineman's handset.
1-8. The Model 3555B can be operated from either
the internal 45V dry cell battery or from the ac line, 115
or 230Vac, 48Hz to 440Hz. A special device is included
in the cover to automatically turn the set off when the
cover is replaced. The set can also be operated from
the central office battery. A jack is provided on the side
of the set for this purpose.
1-9. ACCESSORY EQUIPMENT SUPPLIED.
1-10. The accessory equipment supplied with the
Model 3555B is listed in Table 1-2.
Table 1-2. Accessory Equipment Supplied
-hp- Part No. Description Quantity
8120-1348 Power Cord 1
1470-0026 Battery, 45 Volt dry cell 1
03555-26510 Test Board 1
5000-7135 Decal, 150 BAL 1
1-11. INSTRUMENT IDENTIFICATION.
1-12. Hewlett-Packard uses a two-section serial
number. The first section (prefix) identifies a series of
instruments. The last section (suffix) identifies a
particular instrument within the series. If a letter is
included with the serial number, it identifies the country
in which the instrument was manufactured. If the serial
prefix of your instrument differs from the one on the title
page of this manual, a change sheet will be supplied to
make this manual compatable with newer instruments or
the backdating information in Appendix C will adapt this
manual to earlier instruments. All correspondence with
Hewlett-Packard should include the complete serial
number.
1-13. 150 BAL MODIFICATION.
1-14. The Model 3555B is shipped from the factory
with a 135 BAL function. If a 150 BAL function is
desired instead of the 135 BAL function, the set can be
converted by simply clipping a shorting wire within the
set, applying a 150 BAL decal (supplied with the set)
over the 135 BAL decal and making only one
adjustment.
1-15. For detailed instructions on modification of the
set refer to Paragraph 5-6. If your set is known to be
within specification tolerances a simplified procedure
can be used to modify the set and is described in
Paragraph 3-69.
1-2