Figure 3. Driver and indicator circuits for one section of an Agilent 84904, 6, 7 K/L
2
Attenuator
DIP plug
1
2
9
10
RF connector
Typical driver circuit
11764-60001/2/3 wire colors
1. Brown
3. Orange
5. Green
7. Violet
9. White
2. Red
4. Yellow
6. Blue
8. Gray
10. Black
11764-60002/3 header
1
2
3
4
5
6
7
14
13
12
11
10
9
8
Brown
Red
Orange
Yellow
Green
Blue
Violet
Gray
White
Black
14
Brown
Red
Orange
Yellow
Green
Blue
Violet
Gray
White
Black
8
1
Figure 3 shows an economical TTL
compatibility driver circuit for a sin-
gle attenuation section which utilizes
and IC relay driver and an inverter. A
TTL “HI” input to the driver switches
in the attenuation card, while a “LO”
will activate the thru line for that sec-
tion. This provides a complimentary
driver for the section which assures
that only one solenoid of the pair is
activated at a time. Diode protection
is required to protect the IC from the
solenoid voltage flyback.
Switch position can be indicated
remotely by utilizing the open and
closed states of the internal coil
contacts. Connected at A and B in
figure 3 are two indicator circuits, one
providing a TTL output and one that
activates an LED. These circuits will
output a TTL “HI (LED lamp ON”) if
the attenuation card is in the RF cir-
cuit, and will output a TTL “LO” (LED
lamp “OFF”) if the thru line is in the
RF circuit. Since current is drawn
through the coil for these circuits,
inadvertent switching is prevented by
limiting the current to 5 mA.
Agilent Technologies assumes no
responsibility for the use of any cir-
cuits described herein and makes no
representation or warranties, express
or implied, that such circuits are free
from patent infringement.
7
11764-60001/2/3
14 pin header colors
1
14
2 Red
13 Brown
3 Yellow 12 Orange
4 Blue
11 Green
5 Gray
10 Violet
6 Black
9 White
7
8
Figure 4. Attenuator switching pinout
Table 1. Solenoid pin and attenuation guide
Section:
Section 1
Section 2
Section3
Section 4
Model Number
Thru
Line
Attn
Card
10
2
6
2
10
2
6
2
1
2
6
2
Thru
Line
0
5
7
11
0
5
7
11
0
5
7
11
Attn
Card
20
8
8
5
20
8
8
5
2
8
8
5
Thru
Line
0
4
9
3
0
4
9
3
0
4
9
3
Attn
Card
30
9
10
9
40
9
10
9
4
9
10
9
Thru
Line
0
6
11
4
Attn
Card
30
7
12
10
84906K/L
Attenuation (dB)
0
Actuating pin
1
11764-60004
plug
Pin number
5
11764-60002/60003
flat
Header pin number
13
84907K/L
Attenuation (dB)
0
Actuating pin
1
11764-60004
plug
Pin number
5
11764-60002/60003
flat
Header pin number
13
84904K/L
Attenuation (dB)
0
Actuating pin
1
11764-60004
plug
Pin number
5
11764-60002/60003
flat
Header pin number
13
Pin 10 is +V Supply
Drive cables
11764-60001
11764-60002
11764-60003
10 pin DIP to 60” long
ribbon cable
10 pin DIP to 14 pin DIP,
8” long
10 pin DIP to 14 pin DIP,
16” long
10 pin DIP to 12 pin Viking
connector, 60” long. Used
with 11713A driver
10 pin DIP to (4) 4 pin BERG
connectors, 30” long. Used
with 87130A or 70611A driver
0
6
11
4
4
7
12
10
11764-60004
11764-60006
3
Table 2. Attenuator section activation guide
Recommended switching sequence: The following switching sequence (ie. which 30 dB section to use for the 84906K/L or which 4 dB section for the
84904K/L should be followed to insure performance to specs.
Attenuation selected
84906K/L
Section 1 (10 dB)
Section 2 (20 dB)
Section 3 (30 dB)
Section 4 (30 dB)
84907K/L
Section 1 (10 dB)
Section 2 (20 dB)
Section 3 (40 dB)
84904K/L
Section 1 (1 dB)
Section 2 (2 dB)
Section 3 (4 dB)
Section 4 (4 dB)
0 dB
1 dB
X
X
2 dB
3 dB
X
X
X
X
4 dB
0 dB
10 dB
X
X
20 dB
30 dB
X
X
X
5 dB
X
X
X
X
6 dB
7 dB
X
X
X
X
X
X
X
40 dB
50 dB
X
X
X
8 dB
0 dB
10 dB
X
X
X
X
20 dB
30 dB
40 dB
X
X
X
X
X
60 dB
X
X
70 dB
X
X
X
9 dB
X
X
X
X
10 dB
11 dB
X
X
X
X
50 dB
60 dB
70 dB
X
X
X
X
80 dB
90 dB
X
X
X
X
Switching notes: Pins relate to 10-pin attenuator header as shown (Table 1), NOT terminating connector on any attached drive cable. Solenoids are magnetic
latching type; drive voltage may be removed after switching. Current is self-interrupting in less than 20 ms.
4
GPIB attenuator/switch driver
Employing programmable step atten-
uators and switches in an automatic
test system becomes an easy task
when the Agilent 11713B/C attenuator/
switch driver is specified into the
system.
The 11713B/C has all of the necessary
features to provide GPIB, USB, or LAN
control of up to four programmable
attenuators of the 84904/6/7 series,
and concurrently up to four electro-
mechanical switches (e.g., the 8671B
or 8762 Series).
The 11713B/C includes an integral
power supply (with short circuit
protection) that can simultaneously
provide 125 millamps at 24 volts
to all contacts for control of the
attenuators and switches, so no
external power supply is needed.
Connecting between the 11713B/C
and the 84904/6/7 step attenuators
is easy with the 11764-60004 drive
cable.
The 11713B/C also features convenient
front panel keys so the user can man-
ually activate the individual attenua-
tion sections and switches when in
the “local” mode. Switching time for
the drivers is less than 10 millisec-
onds.
Optional calibration data for the
Agilent 84904/6/7
Use of calibration data (i.e., accuracy,
recorded, data of a device’s charac-
teristics) has always been an effective
means of reducing measurement
uncertainty at RF and microwave
frequencies. Step attenuators have
long been used as reference stan-
dards in the measurement of gain,
attenuation, and receiver sensitivity.
Since the accuracy specifications
include margins for frequency
response and unit-to-unit variations,
calibration data can improve overall
measurement uncertainty.
Calibration data is available as
Option 8490xx-UK6 and is generated
from measurements made by an
Agilent network analyzer.
Option 8490xx-UK6 provides a tabu-
lar list of attenuation and reflection
coefficients in 250 MHz steps from
1500 MHz to 40 GHz. Measurements
are traceable to NIST (National
Institute of Standards and
Technology, formerly NBS) standards
and feature very low measurement
uncertainties (See tables 3 and 4).
For devices with option 8490xx-006
and option 8490xx-106, option
8490xx-UK6 and NIST traceability are
not available.
Table 3. Agilent 84904/6/7K/L reflection
coefficient data uncertainty
Frequency Range (GHz)
dc to 12.4
14.4 to 26.5
26.5 to 34
34 to 40
± .017
± .023
± .025
± .028
Table 4. Agilent 84904/6/7K/L attenuation data uncertainties
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