Power Meter Operation
Setting Measurement Limits
2-48 Agilent E4419B User’s Guide
default values depends on the measurement units in the currently 
selected window - see Table 2-6. 
The window based limits can also be set to output a TTL logic level at the 
rear panel Rmt I/O port when the predefined limits are exceeded. You can 
switch the rear panel TTL outputs on or off; set the TTL output level to 
active high or low; and determine whether the TTL output represents an 
over limit condition, under limit condition or both. 
The TTL connector is an RJ-45 series shielded modular jack assembly 
with the TTL output pins connected as shown in Figure 2-14.
Table 2-6:  Range of Values for Window Limits
Window 
Units
Max Min
Default
Max Min
dB +200 dB -180 dB 60 dB -120 dB
dBm +230 dBm -150 dBm 90 dBm -90 dBm
% 999.9 X% 100.0 a% 100.0 M% 100.0 p%
W 100.000 XW 1.000 aW 1.000 MW 1.000 pW
HP4402.book  Page 48  Thursday, November 30, 2000  1:39 PM