Frequency Response - H Heuer Instruments UMDT51A User Manual

Frequency Response

1. Make the connections between the Test circuit and the LT51 as in Fig. 3.1.
2. Turn the LT51 ON. [after Reset: Ztx = 600, Zrtx = HiZ 600, TX Source =
OFF, TX Freq =10 kHz, Mode = TX-RX (4W)]
Press the [f5] soft-key to select the 'NEXT Loss' measurement. This will
3.
enable the SINE Transmitter at 10 kHz, 0 dBm on the LT51 TX terminals
and set the LT51 RTX (input) impedance to 600  terminated.
4. Press the
Use the knob to set the span to 4.5 kHz.
5. Press the
Hz, using the Knob or Keypad, and press the
box, or appropriate [fx] soft-key if using keypad.
6. Press the
level measured at 1000 Hz.
7. Press the
using the Knob or Keypad, and press the
box, or appropriate [fx] soft-key if using keypad. Repeat for all frequencies in
the Specification template.
Press the [f5] soft-key, to set Sweeping to 'ON'. This will automatically
8.
sweep across the 4.5 kHz BW to show a graph of the Frequency Response
in the spectral display. Use the Marker to read the frequency response at
each frequency.
9. The display will show the received level and frequency over the 4.5 kHz BW
at the RTXab input terminals. Press
to toggle between displays of the signal.
LT51 User Manual
key, followed by the [f1] soft-key to set the frequency Span.
key followed by the [f4] soft-key to set the TX Freq to 1000
key, followed the [f4] soft-key to set the Zero Offset for the
key followed by the [f4] soft-key to set the next TX Freq
Testing VF-PCM Multiplexers
button to clear the Dialog
button to clear the Dialog
(Spectral) or (Numerical)
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