Anritsu V255 Gen II Ultra-Wideband Bias Tee User manual

OPERATION AND MAINTENANCE
MANUAL FOR MODEL V255 GEN II ULTRA-WIDEBAND BIAS TEE
1. INTRODUCTION
This manual describes the Model V255 Ul-
tra-Wideband Bias Tee (Figure 1). It provides speci-
fications and a list of precautions the user should ob-
serve when using this device.
2. DESCRIPTION
The V255 Gen II Ultra-Wideband Bias Tee is de-
signed to meet the high electrical performance re-
quirement of passive components in optical commu-
nication networks. Given a broader bandwidth of
50 kHz to 65 GHz, with low insertion losses and very
good return loss, makes it ideal to use in 40 Gbps
systems to bias optical modulators and broad band
data drivers. It’s fast rise time and flat group delay
performance allows extremely accurate measure-
ments within a laboratory environment. The V255
Bias Tee comes with a standard V Connector® that
assures excellent impedance match across the avail-
able wide bandwidth. The DC signal can be applied
or extracted from the bias tee through an SMC con-
nector at the third port. As with our other bias tees,
the V255 also has a one-year warranty.
3. SPECIFICATIONS
Table 2 provides performance specifications.
4. PRECAUTIONS
ANRITSU V255 Bias Tee is a high-quality, precision
laboratory device and should receive the same care
and respect afforded other such components. Com-
plying with the following precautionary notes will
guarantee longer component life and less equipment
downtime due to connector failure. Also, such com-
pliance will ensure that RF component failures are
not due to misuse or abuse—two failure modes not
covered under the ANRITSU warranty.
a. Beware of Destructive Pin Depth on Mating
Connectors. Measure the pin depth of the con-
nector that mates with the RF component, before
mating. Use an ANRITSU Pin Depth Gauge
(Figure 2) or equivalent. Based on RF compo-
P/N: 10100-00040
REVISION: B
PRINTED: SEPTEMBER 2001
COPYRIGHT 2001 ANRITSU COMPANY
490 JARVIS DRIVE l MORGAN HILL, CA 95037-2809
Figure 1. Model V255 Gen II Ultra-Wideband Bias Tee

nents returned for repair, destructive pin depth
on mating connectors is the major cause of fail-
ure in the field. When an RF component connec-
tor is mated with a connector having a destruc-
tive pin depth, damage will likely occur to the
RF component connector. (A destructive pin
depth has a center pin that is too long in respect
to the connector’s reference plane.)
The center pin on an RF component connector
has a precision tolerance measured in mils
(1/1000 inch), whereas connectors on test de-
vices that mate with RF components may not be
precision types. Their pins may not have the
proper depth. They must be measured before
mating to ensure suitability. When gauging pin
depth, if the test device connector measures out
of tolerance in the “+” region, the center pin is
too long. Mating under this condition will likely
damage the RF component connector. On the
other hand, if the test device connector mea-
sures out of tolerance in the “–” region, the cen-
ter pin is too short. While this will not cause any
damage, it will result in a poor connection and a
consequent degradation in performance.
The pin depth for the V255 bias tee is: 0.000 to
0.003
b. Avoid Over Torquing Connectors. Over
torquing connectors is destructive; it may dam-
age the connector center pin. Never use pliers to
tighten connectors.
c. Avoid Mechanical Shock. RF components
are designed to withstand years of normal bench
handling. However, do not drop or otherwise
treat them roughly. They are laboratory-quality
devices and, like other such devices, require
careful handling.
d. Keep Bias Tee Connectors Clean. The pre-
cise geometry that makes the RF component’s
high performance possible can be easily dis-
turbed by dirt and other contamination adher-
ing to connector interfaces. When not in use,
keep the connectors covered. Refer to paragraph
5 for cleaning instructions.
5. MAINTENANCE
ANRITSU recommends that no maintenance other
than cleaning be attempted by the customer. The
bias tee should be returned to ANRITSU for repair
and/or service when needed.
The traditional method of cleaning V Connectors
with a cotton swab and alcohol can break the male
connector pin on the precision connectors. The rea-
son: the cotton swab has a larger diameter than the
connector (that is, the area between the inner wall
and the center pin.)
We still recommend using a cotton swab; however,
you need to trim the swab before inserting into the
connector.
For best results, observe the following precautions:
·Use either the finger saver that has been pro-
vided with the bias tee or use a 5 inch-pound
torque wrench when connecting to other de-
vices. No other tools are recommended.
·Always spin the coupling nut to tighten con-
nections. Spinning the connector body causes
premature wear to the connector interface.
Do not disturb connector center pin. Improper use
(see above) of a cotton swab or other such probe to
clean the inner connector may cause the center con-
ductor to hinge on its bead and weaken or shear the
internal connection.
2 V255 OMM
0
1
2
3
45
1
2
3
4
211 2
Figure 2. Pin Depth Gauge

V255 OMM 3
Table 1. Performance Specifications, 1 of 2
Specification V255
Frequency Range, 3dB BW 50 kHz to 65 GHz
30 kHz to 65 GHz typical
Insertion Loss 1.5 dB to 65 GHz typical
Return Loss 12 dB to 65 GHz typical
Rise Time 3 ps typical
Group Delay 125 ±2 ps typical
Max DC Voltage 10V (maximum)
DC current 400 mA (maximum)
Isolation –50 dBm (minimum)
Operating Temperature 0°C to 80°C
Outline Drawing, V255

4 V255 OMM
Figure 2. Typical V255 Insertion Loss and Return Loss, 1 kHz to 1 MHz
Figure 4. Typical V251 Insertion Loss and Return
Loss, 40 MHz to 65 GHz
Figure 3. Typical Isolation between Data I/P and DC
Port
Figure 6. Typical Group Delay Performance measured
on V255