TTS2  Digital Recorder

This was our original 24bit recorder. Production was discontinued in 1998, with most of the systems still installed on survey vessels. However refurbished systems with up to 120 channels are still available for hire.

On this page:
Key Features • Brief Specifications

SYSTEM2 Key Features include:

• Optimised for high resolution surveys - only 300ms dead time between shots for any configuration.
  
  
• Up to 120 seismic channels.
  
  
• ¼ ms. to 2ms. sample rates
  
  
• True pre-emptive multi-tasking real time operating system controls all data handling
  
  
• Windows 3.1© based GUI, for ease of interfacing and third party support.
  
  
• Crystal 24 bit Sigma-Delta seismic ADC's on all channels, give 120 dB dynamic range.
  
  
• Analog multiplexed output and single trace gather.
  
  
• Every seismic channel data can be displayed every shot, on a high resolution video screen - even up to 120 channels.
  
  
• High speed, hard copy output.
  
  
• Support for most popular 'bird' controllers and source controllers.
  
  
• Automatic and manual integrated system test and analysis.
  
  
• Automated cable tester, with capacitance measurement.
  
  
• Interfaces with direct, pre-amplified and transformer coupled streamers.
  
  
• Unrivalled hardware and software support, direct from our workshop
  
  
• No agents, all systems are installed by our own engineers.
  
  
• Approved by all major oil companies.

SYSTEM2 Brief Specifications:

Electrical:

Analog to Digital Conversion
Type: Delta-sigma
Make/Model: Crystal Semiconductor 5321/5322
Resolution: 24bits
Converters per channel: 1

Maximum Channels per Sample Rate
120 @ 2ms.
120 @ 1ms.
60 @ 1/2ms
24@ 1/4ms.

Channel Programming
Minimum number: 12
Channel selection multiple: 4
Channels per analog module: 64
Auxiliary channels: 0 or 4

Average instantaneous dynamic range
116dB @ 24dB fixed gain, 1ms. sample rate

Input characteristics
Transformerless, instrumentation amplifier, Varistor protected
Input impedance 1M*.

Maximum input signal
580mV. rms @ 24dB K gain.

Equivalent input noise
(source resistance 2,000*)
typically, 0.7uV @ 1ms and 24dB K gain

Common mode rejection
Better than 90dB @ 50Hz. 2V.

Overall fixed gain
Base gain of 24dB or 30dB.
Software adjustable from +0 to +24dB., in steps of 6dB.

Interchannel Crossfeed
Less than -90dB at full scale input.

Total Harmonic Distortion
Typically 0.002% @ 24dB, 7.8Hz, full scale -6dB

Low Cut filter
Type: analog, Butterworth
Slope: 18dB/octave.
Selection: software, 4 fixed frequencies.
Frequency: programmable by plug-in module.
Filter out: 6dB @ lowest filter program.

Anti-alias Filter
Type: digital, FIR, linear phase
Stop band attenuation: 130dB min.
Cut-off frequencies: 205Hz. @ 2ms.
411Hz. @ 1ms.
825Hz. @ 1/2ms.
1650Hz. @1/4ms.

System Master Clock
Frequency: 1.024Mhz.
Tolerance: < 10ppm.

Digital Data Formats - SEGD
8058 - 32bit IEEE demultiplexed
8015 - 20bit demultiplexed

Record Length
Minimum length: 96ms.
Selection interval: 128 samples.
Maximum length: depends on channels/sample rate, no limits on typical operation - 9.9s @ 120 channels 1ms.

Tape Interface
Type: SCSI-1 (8bit)
Media: 3490E, DAT

QC Features:

Test generator (internal)
Sinewave: 18 levels: 512mV to 1 uV in 6dB steps
8 frequencies:7.8Hz to 1000Hz.
Distortion: <0.002%
Pulse: positive, negative, to SEG specs.
Terminated inputs.

Cable Testing (integral)
Impulse test with transducer connected.
Continuity, Leakage, Capacitance, Manual and Auto modes.

VDU monitor
Raster scan of Seismic channels
Analysis of test records by histogram and table.

Near trace gather (profiler)
Select any channel
Compressed analog output with trigger
Fixed output data stream, sample rate independent.

Oscilloscope monitor
Realtime multiplexed analog output, from each analog box, or all channels.