5305 Spectrum Drive, Frederick, MD 21703-7362 TEL: 301-846-9222, 800-638-2048 Fax: 301-846-9116
web: www.weinschel.com email: sales@weinschel.com
111
10/23/01
Model 940-60 dc to 4.0 GHz
Model 940-114 dc to 2.0 GHz
Precision Continuously Variable Attenuator 5 Watts
Choice of SMA or Type N Connectors
Features
oWide Variable Attenuation Range - Variable attenua-
tion range of 60 dB for Model 940-60 and 114 dB for
Model 940-114, with minimum insertion loss at 6 dB.
oApproximately Linear Calibrated Dial - Direct reading
dial individually calibrated in approximately linear 1 dB
increments from 6 dB to full scale.
oRugged - Designed to meet the environmental require-
ments of MIL-A-24215.
oLong Life - These variable attenuators offer a cycle life
of up to 10,000 cycles. Optional models are also avail-
able to extend the life to 50,000 cycles.
Specifications
NOMINAL IMPEDANCE: 50 Ω
FREQUENCY RANGE: Model 940-60: dc to 4.0 GHz
Model 940-114: dc to 2.0 GHz
INCREMENTAL ATTENUATION RANGE:
Model 940-60: 60 dB
Model 940-114: 114 dB
CHARACTERISTIC INSERTION LOSS, RESIDUAL:
6 dB nominal
DIAL CALIBRATION (in 1 dB increments):
Model 940-60: 6 to 66 dB
Model 940-114: 6 to 120 dB
DIAL INCREMENTS: 1 dB
RESOLUTION OF SCALE:
Model 940-60: ~ 115°
Model 940-114: ~ 270°
CYCLE LIFE: A cycle consists of a rotation from minimum
to maximum and back to minimum
Model 940-XX-XX : 10,000
Model 940-XX-XX-1: 50,000
PHASE SHIFT WITH CHANGE IN ATTENUATION:
1° per dB x f(GHz) maximum
POWER RATING: 5 watts average to 40°C ambient tem-
perature, derated linearly to 0 watts @ 85°C. 500 watts
peak (5 µsec pulse width; 0.5% duty cycle).
POWER COEFFICIENT: < 0.005 dB/dB/watt
TEMPERATURE COEFFICIENT: <0.001 dB/dB/°C
TEMPERATURE RANGE:
Operating: 0°C to +85°C
Nonoperating: -55°C to +125°C.
FREQUENCY SENSITIVITY:
Model 940-60: 0.05 x A x (F - Fd) dB
Model 940-114: 0.1 x A x (F - Fd) dB
A = Attenuation setting in dB, Fd = Dial cut frequency in
GHz, F= Operation frequency in GHz
CALIBRATION: Calibration frequency for Model 940-60 is
2 GHz and 1 GHz for 940-114. Test data is available at
additional cost.
CONNECTOR: SMA or Type N connector per MIL-STD-
348 interface dimensions - mate nondestructively with
MIL-C-39012 connector.
Connector Options INPUT (J1) OUTPUT (J2)
11 SMA, Female SMA, Female
12 SMA, Female SMA, Male
22 SMA, Male SMA, Male
33 N, Female N, Female
34 N, Female N, Male
44 N, Male N, Male
CONSTRUCTION: Aluminum body and stainless steel
connector; gold plated beryllium copper contacts. Knob is
included with each unit.
WEIGHT: Net 1,570 g (3 lbs, 8 oz)
Model ACCURACY*
940-60-XX + 0.25 dB or 0.4% @ 2 GHz
940-114-XX + 0.25 dB or 0.4% @ 1 GHz
940-60-XX-1 + 0.5 dB or 1% @ 2 GHz
940-114-XX-1 + 0.5 dB or 1% @ 1 GHz
*Whichever is greater.
DIRECT READING DIAL ACCURACY:
MAXIMUM SWR:
Frequency Range (GHz) SWR
dc - 1 1.50
1 - 2 1.60
2 - 3 1.70
3 - 4 1.80
5305 Spectrum Drive, Frederick, MD 21703-7362 TEL: 301-846-9222, 800-638-2048 Fax: 301-846-9116
web: www.weinschel.com email: sales@weinschel.com
112
10/23/01
MODEL NUMBER DESCRIPTION:
Example:
940 - XX -XX-*
Basic Model
Number
Attenuation
Value (dB)
Connector Options
ACCESSORIES
ATTENUATOR STAND, MODEL 940 Z: This stand allows a
user to easily mount any Model 940 for those bench
applications.
*Add -1 for long life version.
PHYSICAL DIMENSIONS:
NOTE: All dimensions are given in mm (inches) and
are maximum, unless otherwise specified.
Model No. DIM A DIM B
940-XX-11 52.3 (2.06) 58.2 (2.29)
940-XX-12 55.6 (2.19) 58.2 (2.29)
940-XX-22 55.6 (2.19) 61.5 (2.42)
940-XX-33 61.0 (2.40) 68.1 (2.68)
940-XX-34 66.0 (2.60) 68.1 (2.68)
940-XX-44 66.0 (2.60) 71.9 (2.83)