Model 1084A/B/C GPS Satellite-Controlled Clock

The Arbiter Systems^®, Inc. Model 1084A/B/C GPS Satellite-Controlled Clock provides the most-needed GPS system clock features in an economical package. Three versions allow you to match your requirements. In the Model 1084A, four LEDs monitor operating status. The Model 1084B adds an LCD setup/status display and keyboard. The Model 1084C adds a large (20 mm or 0.8 in.) LED time display.

In all versions, one BNC output provides modulated IRIG-B while another BNC output is jumper configurable for IRIG-B unmodulated or Programmable Pulse. Both outputs have substantial drive capability, and can easily drive multiple loads wired in parallel. A third output is jumper configurable for either one pulse-per-second, IRIG-B unmodulated, or IRIG-B modified Manchester (IEEE Standard 1344 high-precision time code). This third output may also be wired (by a simple modification) to any of the other digital signals generated inside the Model 1084A/B/C. These signals include rates of 1 PPH, 1 PPM, 10 PPS, 100 PPS, 1 kPPS, 10 kPPS, 100 kPPS, 1 MPPS, 5 MPPS, and 10 MPPS; IRIG-E, H, and D; Programmable Pulse, or Locked to satellite. Programmable Pulse generates an output pulse every 1 to 60000 seconds, daily at a specified time, or at a specified time of year; pulse duration is 0.01 to 600 seconds. An optional fiber-optic output generates 1 PPS or IRIG-B in either unmodulated or modified Manchester format. Also, an event timer input measures time of occurrence of an applied pulse to 100 ns resolution. Up to 500 events may be stored.

The Model 1084A/B/C includes two Form C (SPDT) failsafe relays, compatible with 129 Vdc digital fault recorder inputs. The first provides a LOCKED indication, and the second can be selected to the FAULT, 1 PPH, or Programmable Pulse functions.

Twelve receiver channels are standard for best performance, especially in difficult locations. The internal backup oscillator is a digitally-compensated crystal oscillator (DCXO) accurate to 1x10^-7 over temperature.

Power options include 85 to 264 Vac/110 to 275 Vdc, with an IEC-320 detachable cordset, 110 to 275 Vdc terminal strip inlet with surge withstand, or 10 to 60 Vdc terminal strip inlet with surge withstand. The terminal-strip versions have a surge-withstand network designed to meet ANSI/IEEE C37.90-1 and IEC801-4 specifications. All power configurations may be retrofitted in the field.

Model 1084A/B/C Specifications

Optional equipment may be shown.

Receiver Characteristics:

Timing Accuracy:

Specifications apply at the 1 PPS output, in the presence of Selective Availability (SA), as of date of publication.

UTC/USNO: ±100 ns rms, 1 PPS output

Typical: < 40 ns rms, in Position-Hold Mode

Internal Oscillator:

Standard: DCXO, 1x10^-7, unlocked

Allan variance: (locked to GPS, in Position-Hold Mode)

1 second: 5x10^-10 (2x10^-10, typical)

1 day: 5x10^-13

Synchronization:

CMOS output signals are synchronized to the 1 PPS output, ±50 ns, maximum.
IRIG-B modulated, ±1 µs, maximum
The leading edge of the start bit of a received RS-232 data message may be selected to trigger the Event A input, providing synchronization with 100 ns resolution.

Position Accuracy:

25 meters, USA Department of Defense Selective Availability (SA) off.
100 meters, Selective Availability on.
Altitude, 140 meters, Selective Availability on.
All specifications rms, 95% confidence, with Position-Hold Mode off and receiving at least four satellites

Satellite Tracking:

Twelve (12) channel, C/A code (1575.42 MHz). Receiver simultaneously tracks up to twelve satellites. Results from all tracked satellites are averaged in Position-Hold Mode or, with Position-Hold Mode off, using least-squares estimation.

Acquisition:

2 minutes typical, cold start
25 minutes, 90% confidence, cold start
30 seconds, 90% confidence, with ephemeris less than 4 hours old
66 seconds, 90% confidence, with almanac less than 1 month old
The GPS Data Backup Battery is now included in the Model 1084A/B/C. This feature improves acquisition time to as little as 15 seconds after a brief power loss by supplying constant power to the real-time clock and RAM in the GPS receiver module.

I/O Configuration:

Connectors:

Three BNC, one IRIG-B Modulated and two user-configurable:

IRIG-B Modulated, bus driver, 4 Vpp, 20 ohms source impedance, drives a 50-ohm load at 3 Vpp
IRIG-B unmodulated or Programmable Pulse; jumper-selectable
1 PPS, IRIG-B unmodulated or IRIG-B modified Manchester; jumper-selectable

Jumper-selectable outputs are 5 V CMOS bus drivers with 10 ohms source impedance and ±75 mA drive capability.

Relay Contacts:

Two (2) sets, Form C (SPDT) fail-safe, 0.3A at 130 Vdc; one is Locked function; the second one is jumper-selectable and may be Fault, 1 PPH, or Programmable Pulse

Programmable Pulse Output:

Four modes:

Every 1 to 60,000 seconds, starts top of the minute
Hourly at a specified offset
Daily at a specified time of day
One-shot at a specified time of year

Pulse duration is programmable from 0.01 to 600 seconds, except in one-shot mode, where the output is Low prior to the specified time and High thereafter.

Event A Input:

One input is available as an alternate function, with a simple hardware modification to the 1 PPS configurable output. The input may be configured to accept an external 1 PPS signal, and measure the deviation from 1 PPS/GPS with 100 ns resolution. Each input may also be configured to record up to 500 sequential events with 100 ns resolution, provided that the events are separated by 11 ms. Event data is stored in battery-backed RAM.

Interface:

Operator:

Display:

Status LEDs (Models 1084A/B/C)
2 x 20 character supertwist LCD (Model 1084B/C)
20 mm (0.8 in.) LED; 9 digits (Model 1084C)

Functions:

Time: UTC or local
Position: latitude, longitude, altitude
Receiver and clock status
1 PPS (input) deviation
Event time

Status LEDs:

Operate (green)
On Line (green)
Unlocked (red)
Fault (red)

Keypad: Eight keys; select display functions or setup menus (Model 1084B/C)

Setup:

Local time offset
Output code select: Local/UTC
Recorder output A
Daylight Saving Time: On/Off/Automatic
Backlight control: On/Off/Automatic
Event input: Event/1 PPS
Programmable Pulse setup
Antenna delay
Clock offset
Out of lock time: 1 to 99 minute(s), Off, or Zero Delay
Auto-Survey: On/Off, Survey duration
Position Hold: On/Off, Position Auto/Manual
Option Configuration and Setup
Serial port: RS-232

System:

RS-232: 1200 to 19,200 baud; 7 or 8 data bits; 1 or 2 stop bits; even/odd/no parity

Interrogate mode

Broadcast modes:

Standard ASCII (IRIG-J)
Extended ASCII
ASCII with Time Quality
ASCII with Time Quality and Year
Vorne large-display time
Status/Alarm
Event data

Connector: Male 9-pin D-sub (TXD, RXD, AUX IN, AUX OUT)

AUX OUT can provide programmable pulse function at RS-232 levels

RS-422/485 transmit only

Second RS-232 port available (1084opt19)

Connector: Male 9-pin D-sub (TXD, RXD)

Certifications and Approvals

CE mark/label and certificate:

Power Requirements:

Standard:: Voltage: 85 to 264 Vac, 47 to 440 Hz, 20 VA maximum or 110 to 275 Vdc, 15 W maximum; Inlet: IEC-320 with fuse and mating cordset. Specify option P01 - P10; Available cordset plug style and specifications are described in the Options and AccessoriesOptions and Accessories section

General:

Physical:: Size: 1 RU rack mount or tabletop, 260 mm deep FMS, Rack mounts included.
508 x 381 x 203 mm (20 x 15 x 8 in.), shipping; Weight: 2 kg (4.5 lbs), net
5.5 kg (12 lbs), shipping
Antenna:: Mounting: 0.75 in. pipe (1 in. - 14 marine) thread; Cable Connection: F-type; Size: 77.5 dia. x 66.2 mm (3.05 x 2.61 in.); Weight: 170 grams (6.0 oz)
Antenna Cable:: Type: RG-6, 15 m (50 ft) provided; Weight: 0.69 kg (1.52 lbs) per 15 m
Environmental:: Operating Temperature: 0° to +50° C (-20° to +70° C typical); Nonoperating Temperature: -40° to +75° C; Humidity: Noncondensing; EMC: Radiated susceptibility: passes walkie-talkie test. Conducted emissions: power supply complies with FCC 20780, Class A and VDE 0871/6.78 Class A. Surge withstand capability (SWC), power inlet: designed to meet ANSI/IEEE C37.90-1 and IEC 801-4

Options:

Except as noted otherwise, only one I/O Option may be installed. Available options are listed below and described in the Options and AccessoriesOptions and Accessories section.

I/O:

Order Number:	Description
1084opt03:	Four Additional Configurable Outputs
1084opt06:	Parallel BCD Output 1 ms Resolution
1084opt17:	BCD with Second RS-232 Port
1084opt19:	Second RS-232 Port [May combine with other I/O options that do not include an additional RS-232 port]
1084opt20:	Fiber-Optic Output, Type ST 820 nm [May be combined with other I/O options.]
1084opt20A:	Four Configurable Fiber-Optic Outputs
1084opt23:	COMTRADE Sample Rate Generator
1084opt27:	Eight-Channel High-Drive IRIG-B Output
1084opt28:	Power System Time, Frequency, and Phase Monitor
1084opt29:	Four Additional Outputs with Dry Contact and +25/50 Vdc
1084opt32:	Internal Network Time Protocol (NTP) Server

Power (select only one):

Order Number:	Description
1084opt07:	IEC-320 Power Inlet, 85 to 264 Vac, 110 to 275 Vdc
1084opt08:	Terminal Power Strip, Surge Withstand, 10 to 60 Vdc
1084opt10:	Terminal Power Strip, Surge Withstand, 85 to 264 VAc, 110 to 275 Vdc

General:

Order Number:	Description
1084Aopt04:	On/Off Switch
1084Bopt01:	LCD Backlight
1084Bopt04:	On/Off Switch
1084Copt01:	LCD Backlight

Accessories:

Included:

Order Number:	Description
AS0028200:	Rack Mount Kit
AS0031000:	1084A/B/C Operation Manual
AS0076200:	GPS Antenna, pipe mountable
CA0021315:	15 m (50 ft) RG-6 Antenna Cable
P01-P10:	Power Cord Available cordset plug style and specifications are described in the Options/Accessories section.

Available:

Order Number:	Description
AS0033100:	Rack Slide Kit
AS0044600:	GPS Antenna Mounting Bracket
AS0044700:	21 dB Pre-Amp, In Line - For use with cable lengths greater than 75 m (250 ft)
AS0044800:	RG-11 Crimp Tool + 25 F-type Connectors
AS0048900:	Antenna Grounding Block Kit
AS0049000:	GPS Surge Protector Kit
AS0062000:	High Interference GPS Antenna and Mounting Adapter Kit
CA0021315:	15 m (50 ft) RG-6 Antenna Cable
CA0021330:	30 m (100 ft) RG-6 Antenna Cable
CA0021345:	45 m (150 ft) RG-6 Antenna Cable
CA0021360:	60 m (200 ft) RG-6 Antenna Cable
CA0021375:	75 m (250 ft) RG-6 Antenna Cable
TF0006400:	RG-6 Crimp Tool
WC0004900:	300 m (1000 ft) Roll RG-11 Cable