Tektronix 1705A, Instruction Manual

Page: 36 / 223

Introduction
1705A Spectrum Monitor
1- 17
1705A
SPECTRUM MONITOR
IN
RF
OUT
HPA
OUT
IN
UP CONVERTER
OUT
VIDEO
EXCITER
70 MHZ
INPUT
DIRECTIONAL
COUPLER
Figure 1-9: Up link Video Exciter, Up converter, and High Power Amplifier (HPA)
showing how to hook up a 1705A Spectrum Monitor to look at the Video Exciter
output
In addition to the other measurements that can be made a quick check of HPA,
antenna, and transponder (as a system) can be made by comparing the exciter
output (using the 70 MHz input) to the incoming signal from the down link
(using the L--Band Input) by simply switching between inputs. See Figure 1-10.
Miscellaneous Uses for the 1705A
The 1705A Spectrum Monitor 70 MHz band covers a frequency range from 45
to 100 MHz, at center screen. The low VHF television channels and major
portion of the FM broadcast band are within the frequency range of the 1705A.
If a spectrum monitoring application within this band of frequencies exists the
1705A can easily be used.