Boonton PIM 21 User Manual - Manual (Page 11)

11 Boonton
F1
F2
Rx
Combiner
Test
Port
DC
DC
int
Batt
P
Display
Ext
DC
Ext.DC
Fuse BATT
Fuse
During the power up sequence all power supply rails (including battery and external DC supply)
are checked. Error messages or advisory messages, in the case of missing external DC, will be
displayed if voltage is outside of the limits.
Also during this sequence an RF calibration of the receiver module is performed using an inter-
nal noise source. This source is stable over a large temperature range and is used as a reference
to automatically adjust the receiver’s calibration if required.
RF carrier powers are constantly monitored when the RF is on, accurate closed loop power set-
ting/control is achieved by comparing the actual carrier power with the stored calibration data
for each RF power detector.
Stable frequency reference is provided by a single 10 MHz crystal oscillator, this reference is
used for all RF frequency generation within the tester.
Power regulation is provided by switching converters for improved efficiency. The test set can
operate with an external DC source in the range of 10 to 16 volts DC. Correct battery charg-
ing is achievable over the same range of voltage through the use of a DC/DC converter in the
charging circuit.