User's Guide

Enhanced AM/FM Synthesizer Instruction Manual OS(R/T)-3(A/H) 29 - 935 MHz 6-1
6 REVISION HISTORY
ISSUE DATE REVISION
1 May 97 • Issue 1
2 Mar 98 • Changes to the AM Analog board (OST-3A128) to improve
performance. ECO #547.
C37 was 220nF is now 100nF and C40 was 8.2pF is now not installed
C45 was 33nF is now 22nF and C49 was 2.2nF is now 1.5nF
R32 was 33kΩ is now 56kΩand R36 was 3k3Ω is now 5k6Ω
3 Mar 00 • Changes to the AM Analog board to improve performance at -40˚C.
ECO #565.
L4 was 1.5µH is now 3.9 µH
• Changes to the FM Analog boards to improve manufacturing. ECO #572
C32 & C33 were 100µF through hole tantalums are now 100µF surface
mount tantalums
• Changes to the OS-3A/H Digital board for compatibility with the new
AM wideband Synthesizers. ECO #579.
Added C15 (10µF) and R41 (221kΩ).
JU1 was added and is installed for AM modules only.
PCB, DIGITAL, OS-3H/P SYNTH was version 2 now version 3.
• Added the new component layouts, schematic diagram and parts lists for
the new AM wideband synthesizer. Wideband referring to only having
to be tune once and working over the whole AM band (118-138 MHz).
4 May 00 • Changes to the OS-3H 128-174 MHz Analog board. ECO #603.
R29 was 18k2 is now 3k92, U10 was MC145191 is now MC145193.
• Changes to the OSR-3H 128-174 MHz Analog board. ECO #609.
R22 was 100R is now 0R0.
• Changes to the OS-3A 118-159.4 Analog board. ECO #601.
R42 & R53 were 137kΩ are now 100kΩ.
Jul 00 • Corrected the SELECT table on the OS(R/T)-3H 128-174 MHz
Schematic diagram (section 4.3.3).