Atec Agilent-8490 Series - Manual (Page 2)

2
Description
Agilent’s coaxial fixed attenuators
provide precision attenuation, flat
frequency response, and low SWR
over broad frequency ranges (dc to
26.5 GHz) at low prices. Attenuators
are available in eight attenuation
values: 3, 6, 10, 20, 30, 40, 50, and
60 dB; with performances specified
from dc to 26.5 GHz; and with choice
of four connector types: Type-N, SMA 1 ,
and APC 3.5 2 .
These attenuators are all tested
on a state-of-the-art precision analyz-
erto assure specifications over
the full frequency ranges. Although
the 8493C is not specified above
26.5 GHz, it performs resonance
free to 34 GHz with only a small
loss in performance.
1. As per USASI Committee C83.2 compatible with OSM, ARM, WPM, BRM, NPM, etc.
2. Mate with MIL-C-71 or MIL-C-39012 connectors.
Quality assurance in testing
The flat frequency response and low
SWR of the attenuators areassured
over the entire frequency range by
full frequency band testing on a state-
of-the-art precision analyzer. Full
frequency band testing ensures that
narrow resonances in the frequency
band are not over-looked. Actual
attenuation values taken at dc, 4, 8,
12, 18, and 26.5GHz are stamped on
the attenuator body for permanent
and easy reference.
Testing each attenuator with a state-
of-the-art precision analyzer brings
standards lab accuracy to production
testing because the system can
determine its own measurement
uncertainties and compensate for
them in the testing process. System
calibration is derived from precise
physical standards which are directly
traceable to the National Bureau of
Standards. In addition, automatic
testing eliminates the possibility of
human error in setting instrument
controls, taking data, or making
calculations.
Precision construction
The attenuators employ a film on
an attenuator card as the resistive
element. The uniformity and repeat-
ability of the film deposition process
result in high accuracy and low SWR
over very wide frequency ranges.
The 8493C features thin-film-
tantalumnitride on a sapphire
substrate for exceptional precision
performance to 26.5 GHz. In fact, it
performs resonance-free to 34 GHz,
the top frequency limit of the APC-3.5
connector.
The choice of connector type and-
material also ensure accurate and
repeatable attenuation. The 8491A/B
attenuators are furnished with Type-N
connectors whose dimensions are
compatible with either MIL-C-71 or
MIL-C-39012 connector specifica-
tions.
These connectors are stainless
steel for long wear and high repeat-
ability. The 8493A/B attenuators are
furnished withSMA type connectors.
The connectors are heat treated
beryllium copperfor greater strength
and wear.
The 8493C is furnished with theAPC
3.5 connector which is compatible
with standard SMA connectors but
is more rugged and offers improved
repeatability over hundreds of con-
nections.