Receive Path - TM-11-5820-695-350035

TM 11-5820-695-35

signal to radio repeater for the radio repeater mode of

(3rd mult) within 1A9 and applied to the metering

operation.

circuits.

(2) The RADIO TO CABLE MODEM

indicator on meter panel assembly 1A15A8 and an

(6) The 4.55 to 4.85 Hz signal is mixed

external traffic out indicator are controlled by the radio-

with the 150 MHz frequency modulated signal

to-cable circuits of 1A12 through the radio patch panel.

(containing the pcm signal and orderwire) in transmitter

For normal output pcm traffic conditions, the RADIO TO

frequency mixer stage 1A9 to produce the 4.4 to 5.0

CABLE MODEM and the external traffic out indicators

GHz carrier output signal which is applied to rf bandpass

are lighted green. If an output pcm traffic failure is

filter 1FL3. The bandpass filter is set to the required

detected by the radio-to-cable circuits in 1A12, the

carrier frequency. The lower side band frequency (local

CNTRL ALARM and external traffic out indicators light

oscillator minus 150 MHz) is selected for the low band of

red. The RADIO TO CABLE MODEM indicator lights

carrier output frequencies (4400 to 4699.9 MHz). The

red only when a functional failure exists in 1A12 and

upper sideband frequency (local oscillator plus 150

actual pcm traffic is present. If pcm traffic is not

MHz) is selected for the high band of output frequencies

present, this alarm is inhibited (remains green) even if a

(4.7 to 5.0 GHz). The selected carrier frequency is

functional failure exists.

passed through rf low pass filter 1FL4 to directional

coupler 1DC1. The main output of the directional

(3) A normally energized relay in

coupler is applied to Switch, Waveguide SA1-679/GRC.

orderwire assembly 1A13 is controlled by the recovered

A secondary output is sent to the radio test set. The

ow sense signal from the radio-to-cable circuits in 1A12.

RADIO TEST SET indicator on 1A15A8 lights red when

If the pcm portion of the input signal from Radio,

the radio test set is turned on and green when it is

Receiver R-1467/GRC-144 is missing, the relay

turned off. In addition, detected forward and reflected rf

becomes deenergized. With the relay deenergized, the

power signals are sent from 1DC1 to alarm monitor 1A5

orderwire signal received from the R-1467/R-144 is

and to the metering circuits in 1A15A8. For normal

applied to the orderwire circuits in place of the

conditions, the RF POWER and REFL RF POWER

recovered ow signal from 1A12.

Thus, orderwire

indicators are lighted green. A loss of rf power output or

communication is maintained when the pcm traffic

a high level of reflected power will cause the associated

portion of the signal from the R-1467/GRC-144 is lost.

indicator and the CNTRL ALARM indicator to light red.

(4) A receiver alarm signal is also

Receive Path. In the receive (radio-to-

applied to the alarm circuit in 1A13 from the R-

cable) signal path through the T-1054/GRC-144, the

1467/GRC-144. If an alarm condition is present in the

combined pcm and ow signal from Receiver, Radio R-

.R-14W7/GRC-144, this signal will cause the CNTRL

1467/GRC-144 is applied to the radio to-cable circuits of

ALARM indicator on 1A15A8 to light red and the

1A12 through orderwire assembly 1A13 and the radio

loudspeaker to sound an audible alarm.

patch panel. Note also in figure 5-6 that the radio patch

panel is used to connect the radio-to-cable circuits of

(5) The pcm aim signal from digital

1A12 in the signal path for the radio repeater mode of

data modem 1A12 summaries the alarm conditions

operation.

within 1A12. It is applied to the alarm circuits in 1A13

along with the transmitter and receiver alarm signals to

(1) The radio-to-cable circuits separate

control the CNTRL ALARM indicator and audible alarm.

the pcm reshaped and retimed for application to the

Since the cable-to radio circuits in 1A12 are not used in

cable system. The recovered ow signal is amplified and

the radio repeater configuration, a cable-to-radio alm

fed back to 1A13 through the radio patch panel along

inhibit signal is applied to the radio patch panel. When

with the recovered ow sense signal. The recovered ow

the radio patch panel is connected in the RADIO

signal is amplified in 1A13 and distributed to Handset H-

REPEATER MODE OF OPERATION, this signal inhibits

156/U, Telephone Set TA-12/PT, the loudspeaker, and

the cable-to-radio alarm circuits in 1A12 from activating

back (thru ow send) to the radio-to-cable circuits in

the CNTRL ALARM indicator and the audible alarm.

1A12. The pcm and ow signals are then combined with

the direct current (from the cable-to-radio circuits) and

Metering Circuits. Signals from various

the composite signal is applied to the cable system.

components in the T4064/GRC-144 are monitored at

The radio-to-cable circuits also provide a pcm output

meter panel assembly 1A15A8. The metering

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