Olson Technology OTM-4870 - Manual (Page 3)

025-000412 Rev. B Page 3
OTM-4870
FREQUENCY AGILE 870MHz
F.C.C. COMPATIBLE TELEVISION MODULATOR
1) INTRODUCTION
The Olson Technology OTM-4870 is a frequency agile, F.C.C. compatible television modulator. This microprocessor-
controlled unit is capable of operation on any frequency from 48MHz to 870MHz and output frequency selection is
possible in 0.0125MHz increments. Output frequencies may be selected in MHz or by channel designation. Standard,
HRC, IRC, or EIA channel plans may be specified. FCC offsets of +12.5KHz and +25KHz are automatically provided
depending on the plan and/or channel chosen.
An RF output level of +60dBmV (minimum) is possible over the operating frequency range of the OTM-4870.
SAW filtering and Olson Technology system design factors insure an out-of-band carrier-to-noise ratio greater than 80dB.
This allows unlimited numbers of these units to be combined.
The OTM-4870 has many advanced features including a menu/button control system, front panel display of channel and
channel ID text, a manual or loss-of-video controlled auxiliary I.F. input with AGC, selectable video AGC, external audio
subcarrier input, configurable audio input, dual IF loops, composite IF loop, BTSC compatibility and more.
The OTM-4870 up-converter section is a high performance tuner with excellent phase noise and frequency response that
exceeds DOCSIS and CMTS specifications.
2) CONTROL OF THE OTM-4870
A.) FRONT PANEL ADJUSTMENTS:
Video and audio modulation levels, video-to-audio carrier ratio, and the RF output level are adjustable by means
of slotted controls accessible through the front panel. There is also a control for the LCD panel contrast which
should be adjusted for proper viewing once the unit is installed.
See section 4 of this manual for more information on these adjustments.
B.) FRONT PANEL MENU ITEM CONTROLS:
Most features of the OTM-4870 are configurable from the front panel by means of the menu/button system which
includes an LCD panel and 5 buttons. The LCD panel displays the menu(s) and the currently-selected configura-
tion or value.
The “UP”, “DOWN”, “LEFT”, and “RIGHT” buttons are used to move between menus, to select configurations,
and to change values. All items except tuning mode and channel number/frequency will instantly change to
match the display. A new tuning mode or channel/frequency takes effect only when you press the “ENTER”
button. To make other changes permanent, press the “ENTER” button.
Note that when changing the output frequency, the unit’s digital synthesizer may become unlocked momentarily
resulting in operation on an undesired frequency until it re-locks. The OTM-4870 will turn its RF output off
anytime the unit is in an unlocked state, thus preventing unwanted interference when changing channels.
As illustrated on page 5 below, there are two menu trees; the main menu tree (on the left) and the sub-menu tree
(on the right). The arrows indicate which buttons to press to move around the menus. Review each menu and the
information below to become familiar with the various functions.
Note
DOCSIS = Data over cable service interface specification
CMTS = Cable modem termination system