HP 8753ET/ES supplemental characteristics (continued)
Frequency offset on/off
Sets the RF source to be swept at a fixed offset fre- quency above the receiver as required in a swept RF/IF, fixed LO, mixer test.
Service menu
Select the desired service test, service diagnostic, ser- vice or verification mode.
Test sequences
Description
Create, edit, save or recall a series of front-panel key- strokes to automate a measurement. Test sequences may contain basic stimulus and measurement func- tions (frequency, power, parameter, format, scale) advanced operations (time domain, limit testing, dis- play marker values) and basic logical branching (IF limit test fails DO sequence 5 or GOSUB).
Storage
Test sequences can be stored internally to a disk drive and can be loaded from a computer over the GP-IB interface. Sequence 6 is saved in nonvolatile storage and can be used as an autostart routine when titled AUTO.
General purpose input/output
Read or write bits to the output port to control exter- nal devices such as part handlers. Eight output and five input TTL lines are available on the parallel port.
Other functions
PAUSE/continue, wait, title sequence, print sequence, duplicate sequence, pause and select.
Time-domain (Option 010)
With the time-domain option, data from transmission or reflection measurements in the frequency domain are converted to the time domain using a Fourier transformation technique (chirp Z) and presented on the display. The time-domain response shows the mea- sured parameter value versus time. Markers may also be displayed in electrical length (or physical length if the relative propagation velocity is entered).
Time stimulus modes
Two types of time excitation stimulus waveforms can be simulated during the transformations, a step and an impulse.
• Low-pass step
This stimulus, similar to a traditional time-domain reflec- tometer (TDR) stimulus waveform, is used to measure low-pass devices. The frequency-domain data should extend from DC (extrapolated value) to a higher value.
• Low-pass impulse
This stimulus is also used to measure low-pass devices.
• Bandpass impulse
The bandpass impulse stimulates a pulsed RF signal (with an impulse envelope) and is used to measure the time-domain response of band-limited devices.
Windows
The windowing function can be used to modify (filter) the frequency-domain data and thereby reduce over- shoot and ringing in the time-domain response. Three types of windows are available: minimum, normal, and maximum.
Gating
The gating function can be used to selectively remove reflection or transmission time-domain responses. In converting back to the frequency-domain the effects of the responses outside the gate are removed.
Remote programming
Interface
HP-IB interface operates to IEEE 488-1978 and IEC 625 standards and IEEE 728-1982 recommended prac- tices.
Addressing
The GP-IB address can be verified or set from the front panel via the local menu and can range from 0 to 30 decimal (factory set at 16).
Pass control
Allows the HP 8753ET/ES to request control of the GP-IB (when an active controller is present) whenever it needs to output to a plotter or printer.
System controller
Lets an HP 8753ET/ES become a controller on the GP-IB to directly control a plotter or a printer.
Talker/listener
Lets the HP 8753ET/ES become an GP-IB talker/listen- er when an external controller is present.
Transfer formats
Binary (internal 48-bit floating-point complex format) ASCII 32- or 64-bit IEEE 754 floating-point format
User-accessible graphics
Using a subset of HP Graphics Language (HP-GL), vector or text graphics may be written on the
HP 8753ET/ES via GP-IB. Up to 5 kbytes of data can be stored at one time (4 bytes per vector, 2 bytes per character).
Interface function codes
SH1, AH1, T6, TE0, L4, LE0, SR1, RL1, PP0, DC1, DT0, C1, C2, C3, C10, E2