HP 11793A Operating And Service Manual page 13

Microwave Converter Model 11793A
3 .
Safety Considerations
This product is a Safety Class I instrument; that is, one provided with a prctective earth terminal. The
Microwave Converter and all related documentation must be reviewed before operation for complete
familiarization with safety markings and instructions. Refer to the Safety Considerations page found a t
the beginning of this manual for a summary of the safety information. Safety information pertinent to
the task a t hand (that is, installation, operation, performance testing, or service) is found throughout this
manual.
4.
Instruments Covered by This Manual
This instrument has a two-part serial number. The first four digits and the letter comprise the serial
number prefix. The prefix is the same for all identical instruments; it changes only when a change is made
to the instrument. The last five digits form a sequential suffix which is unique to each instrument. The
contents of this manual apply directly to instruments having the serial prefix listed under Serial Numbers
on the title page.
An instrument manufactured after the printing of this manual may have a serial prefix that is not listed
on the title page. This unlisted serial prefix indicates that the manual for this instrument is supplied with
a Manual Changes supplement that documents the differences.
In addition to change information, the supplement may contain information for correcting errors in the
manual. To keep this manual as current and accurate as possible, Hewlett-Packard recommends that you
periodically request the latest Manual Changes supplement. The supplement is identified with the manual
print date and part number that appear on the title page. Complimentary copies of the supplement are
available on request from your nearest Hewlett-Packard office.
For information concerning a serial prefix not listed on the title page or in the Manual Changes
supplement, contact your nearest Hewlett-Packard office.
5. Description
The HP Model 11793A Microwave Converter down-converts microwave input signals in the range from
1.3 to 26.5 GHz. For frequencies below 1.3 GHz, signals are routed directly to the input of the measuring
instrument. Instruments suitable for lower frequency measuring are the HP 890 1B Modulation Analyzer
or the HP 8902A Measuring Receiver.
For input signals above 1.3 GHz, the Microwave Converter routes the signal through an internal mixer
which mixes the input signal with an external local oscillator. The difference frequency (that is, the
intermediate frequency or IF) is filtered, amplified, and then appears a t the IF OUTPUT connector. The IF
should be between 10 and 700 MHz.
The Microwave Converter requires a +8 dBm leveled output from the LO. For LOs with insufficient
power above 18 GHz, an optional internal amplifier ( 1 8 GHz to 26.5 GHz) is available. The measuring
instrument controls switching of the RF path and of the LO amplifier via a rear-panel connection on the
Microwave Converter.
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