FireFox Synthesizer User Manual
46
© 2006 Jackson-Labs
3.4.2 Can the FireFox system be powered by a battery?
The FireFox system requires a regulated 12.0V power supply to operate properly. A power source
such as a Lead Acid type battery will have an output voltage ranging between 11V (discharged) to
over 14V (charging), and is thus not suitable for powering the FireFox board.
A 12.0V pre-regulator with over-voltage protection can be used to drive the FireFox system from a
vehicle power system.
Contact Jackson Labs for modification of the FireFox desktop unit if a 12V DC input is required.
3.4.3 What are the mixer connections on the front panel used
for?
The FireFox unit includes a general purpose mixer accessible from the front panel. A mixer is used
to generate a signal consisting of the difference of two input signals. Mixers can be used to shift
high-frequency signals into lower frequency bands. This is useful when trying to receive high
frequency signals; see the following example:
An FM modulated signal at 1.40GHz is to be received using the FireFox and a standard FM radio.
The input signal has to be transformed from 1.40GHz to 100MHz to be receivable by the FM Radio.
For this example, we will select a Local Oscillator (LO) Frequency of 1.50GHz. The LO input is
simply driven by the FireFox RF output signal via a BNC jumper cable, so the FireFox is set to
generate the 1.5GHz. The received RF input signal is then connected to the RF input. Mixing the
1.5GHz LO frequency with the 1.4GHz RF signal will generate a 100MHz mixing product (the
Intermediate Frequency, or IF signal), which is basically the RF signal shifted to 100MHz. The IF
output can now be connected to the FM radio tuned to 100MHz. The received signal will now be
audible by the radio.
Typical signal levels at the mixer inputs are -20dBm to 5 dBm for the RF input, and 0dbm for the LO
input. Care must be exercised to avoid driving the Mixer RF and LO inputs above 10dbm. Driving
the inputs above this level could damage the mixer.
The mixer can be disabled in the menu settings to reduce potential interference.
3.4.4 How can I calibrate the FireFox Signal Generator?
The FireFox Signal Generator never needs frequency calibration, it automatically and continuously
calibrates itself using the GPS signals.
The RF analog signal output level is calibrated at the factory, and it is recommended that the user
calibrates the unit annually to maintain output amplitude accuracy in absolute power mode (when
using the dBm indicator in the LCD). The unit has sophisticated calibration software built in, and it
can automatically calibrate itself completely without user interaction.
You will need the following equipment to calibrate the FireFox:
1) Agilent E4418B or E4419B power meter with DB-9, RS-232 serial port option
2) Agilent 8482A power sensor (or any other Agilent power sensor with -30 dBm to 10 dBm and
2MHz to 1.64GHz range
3) Short BNC to N type adapter to connect the power sensor to the FireFox BNC RF output
connector
Summary of Contents for FireFox
Page 1: ...FireFox Synthesizer User Manual Document 0012008 Version 004 Date 10 April 2008...
Page 2: ...FireFox Synthesizer User Manual Copyright 2008 Jackson Labs...
Page 34: ...FireFox Synthesizer User Manual 28 2006 Jackson Labs...
Page 46: ...FireFox Synthesizer User Manual 40 2008 Jackson Labs SOURce POWer...