Olson Technology OTM-4870 - Manual (Page 8)

025-000412 Rev. B Page 8
AUX IF
This LED, when on, indicates that the current IF source is the AUX input at the rear panel.
LCD DISPLAY PANEL
This displays menu and status information.
OUTPUT RF LEVEL
This control is used to set the RF output level. If the OTM-4870 is feeding a system or network with many
channels, it is suggested that it be operated at an output level of +55dBmV minimum to prevent degradation of
the C/N ratio of that channel. If lower output levels are required, place an in-line attenuator at the RF output.
Note that the OTM-4870 may be capable of output levels greater than +60dBmV on some channels. The
specifications for spurious performance, etc. are based on a maximum operating level of +60dBmV. This unit
may not meet its full specification if operated at greater that +60dBmV out.
RF ON
This LED indicates the output RF status.
5) REAR PANEL CONNECTIONS
OTM-4870 REAR PANEL
RF TEST
This output is approximately 20dB below the main RF output and may be used for monitoring or test.
RF OUT
This output is (typically) +61.0dBmV. Over the frequency range of 48.250 to 865.250MHz
IF IN
This is composite IF input at approximately +18dBmV with 44MHz center frequency and 6MHz bandwidth
feeding the output tuner. In normally configured applications, this input is usually connected to composite IF
out. The OTM-4870 is shipped from the factory with this jumper in place.
IF OUT
This is the composite IF source for the analog TV modulator, after the saw filter, with video carrier at
+18dBmV at 45.75MHz. Audio is 41.25MHz and is 12 to 18dB lower than video. In normally configured
applications this output is usually connected to composite IF IN. The OTM-4870 is shipped from the factory
with this jumper in place.
AUX IN
This is the AUX IF input. This input is before the SAW IF section and normally expects an IF input level of
+38 dBmV. It has AGC which will allow levels to vary as much as
±
5dB while holding the RF output level
constant.
This input may be enabled by shorting the AUX SELECT terminals on the rear panel, by front panel control,
or by loss of video.