EIP 545A - Theory of Operation. Hardware

THEORY OF OPERATION - HARDWARE
When measuring a signal frequency greater than 26.5 GHz the 548A using the Option 06 Frequency Exten-
sion with a model
590 kit and a 91 remote sensor, down converts the input to approximately 1.0 GHz. This
signal is then fed to the Band 3 input, where a second conversion produces a 125 MHz IF.
A multiplier chain increases the VCO output frequency to the 5.28-6 GHz range, which is referenced to
the time base. See Figure
06-1. This signal provides the local oscillator (LO) power, which is transmitted
to the remote sensor, an external harmonic mixer. When the input frequency and harmonics of the LO,
(generated in the mixer) combine, a first
IF is generated in the range of 1.00-1.35 GHz.
A diplexer separates the LO and IF signals received from the harmonic mixer. The level of the IF is then
increased to a minimum of
-25 dBm via the IF amplifier, then supplied to the Band 3 converter input.
- --
)E& SENSOR
(NOT PART OF OPTION 061
1- -
--
BAND 3 INPUT , J113
$+* ,
FRONT
PANEL
Figure 06-1. Frequency Extension Block Diagram
Scans by ArtekMedia © 2007