Axcera Innovator CU10BT/CU0T-1, Инструкция по эксплуатации

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Innovator CU10BT-CU5000BT Analog Transmitter Board Descriptions
Instruction Manual, Rev. 0 48
J6
IF Input
Mixer Mixer
J7
RF Output
1 GHz
TCXO
Fract-N PLL
Integer-N PLL
Integer-N PLL
10 MHz
TCXO
External
10 MHz
Detection
J10
External
10 MHz Input
VCO 1
VCO 2
Band Switching
from Ext Control
1 GHz
1.1-1.9 GHz
(A4) Frequency Agile Upconverter Board (1309695)
The board takes a 44 MHz or 36 MHz IF signal and converts it to a TV channel in the
range of 54-860 MHz. The IF input signal, (≈-8dBm level), is connected to J6 on the
board. The IF first passes through a frequency response pre-corrector, consisting of
R145, C188, R 146 and C189. The pre-corrector circuit compensates for any response
variation in the ceramic filter used to pick the appropriate conversion sideband. The
pre-corrected signal is then converted to a second IF centered at 1044 MHz using U16,
U18 and associated components. The signal is next applied to a second mixer, U15,
where it is converted to the final RF channel frequency. The signal is then sent to a low
pass filter that removes unwanted conversion products above 1 GHz, amplified by U21
passed to another low pass filter that removes unwanted conversion products above 1
GHz, amplified by U20 and connected to J7 the RF output jack for the board (≈-3dBm
level).
The upconverter has two local oscillators, LO1 and LO2. The LO1 oscillator consists of
U1, U2, U5, U6 and amplifiers U3 and U4. The LO1 oscillator operates at 1 GHz for 44
MHz IF inputs and is used to convert the signal to 1044 MHz. In 36 MHz IF systems, this
oscillator circuit operates at 1.008 GHz. The Red LED DS4 will light if the PLL for the
LO1 oscillator is not locked.
The second LO, LO2, consists of two VCOs, U26 and U31, that are used to generate the
second LO. One VCO operates from 1.1-1.5 GHz and the second from 1.5-1.9 GHz. The
Red LED DS2 will light if the PLL for the LO2 oscillator is not locked.
Both of the LOs, LO1 and LO2, are locked to an on board 10 MHz VCXO. The 10 MHz
VCXO circuit consists of U36, U39, the VCTCXO Y1 and associated components. When
an external 10 MHz signal is applied to J10 on the board, the internal VCXO is locked to
the external 10 MHz, otherwise, it is free-running. The Red LED DS6 will light if an
External 10 MHz reference is present. The Red LED DS3 will light if the PLL for the 10
MHz oscillator is not locked.