Model 1093A/B/C GPS Satellite-Controlled Clock (500 ns)

Model 1093A/B/C delivers better than 500 ns accuracy and includes the most highly sought after features in a precision time clock as standard.

With two terminal strip outputs providing unmodulated IRIG-B and 1 PPS signals, the 1093 is capable of driving multiple loads in parallel. An optional modulated IRIG-B port is available adding greater flexibility.

Like other Arbiter clock models, various options are available to add features such as NTP (Network Time Protocol) & IEEE1588 PTPv2 support, four additional configurable outputs, high drive IRIG-B outputs, power system time, frequency, and Phase Monitor functions, one Form C (SPDT) fail-safe, LOCKED relay that is compatible with 129 Vdc digital fault recorder inputs; plus many more.

  • Accuracy< ±500 ns typical
  • Unmodulated IRIG-B and 1 PPS included, modulated IRIG-B optional
  • Internal NTP & IEEE1588 (PTPv2) server, dual Ethernet ports (optional)
  • High Drive IRIG-B outputs (optional)
  • One Form C (SPDT) fail-safe locked relay (optional)
  • Power System Time, Frequency and Phase Monitor (optional)
  • 1093A supports four LEDs for monitoring operating status.
  • 1093B adds to the LEDs an LCD display and keypad, providing easy access to setup and system status information.
  • 1093C includes both the operating status LEDs, the LCD display and keypad, and includes a large LED time display.


Receiver Characteristics

Timing Accuracy

Accuracy Note Specifications apply at the 1 PPS output, in the presence of Selective Availability (SA), as of date of publication
Accuracy UTC/USNO ± 500 ns peak

Position Accuracy

10 meters, rms, 90 % confidence

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.


  • 150 seconds typical, cold start
  • 15 minutes, 90 % confidence, cold start
  • 40 seconds, with almanac less than 1 month old
  • 15 seconds, with ephemeris less than 4 hours old
  • The GPS Data Backup Battery is now included in the Model 1093s. 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

Output Connectors

Two standard: one IRIG-B Unmodulated and one 1 PPS; Type: bus driver, 5 V CMOS; 10 ohms source impedance; ± 75 mA drive capability; pluggable terminal strip.
Open-drain FET drivers (400 V, 220 mA, 1 W power dissipation) can also be fitted; contact tech support.

Event Inputs

One event timer channel with 1 µs resolution is standard. This function may be driven by the start bit of a received character on the serial port, or (by internal connection) an external 5 V CMOS/TTL signal at one of the terminal strip connectors.

Programmable Pulse Output

One programmable output pulse (by a jumper connection) that may be output on a terminal strip connector or the AUX OUT pin on either RS-232 Port.
Four modes:

  • Every 1 second 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 seconds to 600 seconds, except in one-shot mode, where the output is Low prior to the specified time and High thereafter.



  • Status LEDs (Models 1093B/C)
  • 2 character x 20 character supertwist LCD (Model 1093B/C)
  • 14 mm (0.56 in) LED; 9 digits (Model 1093C)
  • Time: UTC or local
  • Position: latitude, longitude, altitude
  • Receiver and clock status
  • 1 PPS (input) deviation
  • Event time
Status LEDs
  • Operate (green)
  • Unlocked (red)
Keyboard Eight keys; select display functions or setup menus (Model 1093B/C)
  • Local time offset
  • Output code select: Local/UTC
  • Daylight Saving Time (Set Summer Time): Off/On/Auto USA/Auto EUR/Auto CUS
  • Backlight control: On/Off/Auto
  • Event input: Event/1 PPS
  • Programmable Pulse setup
  • Antenna delay
  • Out of lock time: 1 minute to 99 minutes, 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


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

Second RS-232 port available (1093opt19)
Connector: Male 9-pin D-sub (TXD, RXD)

RS-422/485 Optional driver can also be fitted (1093opt94)
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

Power Requirements


Voltage (Option 07) 85 Vac to 264 Vac, 47 Hz to 440 Hz, 20 VA maximum or 110 Vdc to 370 Vdc, 15 W maximum
Inlet (Option 07) IEC-320 with fuse and mating cordset. Specify option P01 – P10

Available cordset plug style and specifications are described in the Options and Accessories section.



Size 1 RU rack mount or tabletop, 260 mm deep FMS, Rack mounts included.
508 mm x 381 mm x 203 mm (20 in x 15 in x 8 in), shipping
Weight 2 kg (4.5 lbs), net
5.5 kg (12 lbs), shipping
Antenna Cable Connection: F-type
Size: 80 mm hex (across flats) x 84 mm tall (3.2 in x 3.3 in), including connector
Weight: 170 g (6 oz)
Antenna Cable Type: RG-6, 15 m (50 ft) provided
Weight: 0.69 kg (1.52 lbs) per 15 m
Antenna Mounting 0.75 in pipe (1 in – 14 marine) thread


Temperature Operating: 0 °C to + 50 °C (- 20 °C to + 70 °C typical)
Nonoperating: – 40 °C 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

Certificates and Approvals

CE mark/label and certificate: