DR-890 On-Line Manual

FEATURES

This unit uses special circuitry to read PCM (Pulse Code Modulation) signals with very high accuracy. With the NTSC mode VCR, it is possible to perform PCM recording and playback in the "Extended Play Mode", delivering quality PCM recording no different from "Standard Mode" PCM recording/playback.

PANEL INFORMATION:

1. POWER SWITCH
   Push-in position is "On" mode. When the switch is on, the power switch lamp lights up.
2. RECORD/PLAY SELECTOR SWITCH
   This switch is for selecting the recording or playback mode. When recording with a VCR, press down to RECORD position. The RECORD indicator (green LED light) will light up at this time. When performing playback, press the switch up so that the PLAY ind icator (yellow LED light) lights up.
   
   When power is turned on, sometimes DECODE/ERROR light might come on. In order to reset this, flip PLAY/RECORD switch to PLAY and back to RECORD.
3. DECODE ERROR INDICATOR
   This PCM digitizing unit has a very powerful error correction system. However, if massive data damage occurs, this light comes on. The occurrence of such massive data damage is caused by VCR malfunction or by playing a tape recorded on a VCR with a slig htly different tracking level.
4. INPUT and FULL SCALE ADJUSTMENT
   Absolute maximum input voltage is +/-15 volts. Input impedance is 5OKohm. The full scale input signal range can be set to +/- 1, 2, 4, or 8 volts full scale.
5. OUTPUT
   Output is fixed at +/-IO volts full scale. This means if a signal was recorded at 1 volt full scale setting, the input/output gain is ten.
6. TRIGGER INPUT/OUTPUT
   The trigger s ignal is recorded along with the data channels on the video track, producing a very stable time relationship between the data channels and the trigger. The trigger input accepts a positive going pulse of 3 volts to 20 volts. When the trigg er is accepted, the trigger LED flashes. To ensure the greatest possible accuracy of the trigger signal/evoked potential, use the Neuro-Corder trigger-out signal to synchronize other equipment.
7. VIDEO-IN TERMINAL
   This is a video signal input terminal for use in playback. It is connected to the Video-Out terminal of the VCR.
   
   VIDEO-OUT TERMINAL
   This is a video signal out terminal for use in recording. It is connected to the Video-In terminal of the VCR.
8. NTSC, PAL/SECAM SELECT
   This feature is optional. For use in USA, NTSC is standard. For other locations, please check your local video signal format. Two small jumpers on the Neuro-Corder video processor board select between the 2 modes (option).
9. WINDOW AND TRIGGER MARKER NUMBER KEYS
   Displays are "Marker", "Seconds", "Set", "Mode"; the gain for channels 1 through 8 are displayed under the window.
   
   The Marker number and Seconds are continuously recorded. The Marker number may be pre-set to any desired value by using the four keys to the right ("up", "fast", "down", "enter"). In addition, the Marker number will automatically increment each time the instrument receives a trigger in "Record" mode. Triggering also re-sets the "Seconds" count to zero. The number displayed in the "Set" field may be changed by a combination of "up", "down", "enter", and "fast" keys. Pressing the "up" key will cause the "Set" number to increment at approximately 1 count/second. Pressing the "down" key will cause the "Set" number to decrement. Pressing "up" or "down" while also pressing the "fast" key will increase the rate of increments or decrements. Holding the "fast" key down while pressing or releasing the "enter" key will re-set the number to zero. Pressing the "enter" key will transfer the set number to the trigger number field and re-set "Seconds" to zero.
   
   The "Mode" field is for reference only. On a DR-890 it will always show the channel mode that is selected while in Record mode.
   
   The +/- Full Scale field for channels 1 through 8 will show the setting of the input range select switches (the rotary switches on the side).
   
   In "Playback" mode the four keys ("up", "fast", "down", "enter") have no effect.
10. CHANNEL MODE
    There are seven channel selection modes. Each mode will access different channels for recording. See the table below for active channels and sampling frequencies which correspond to each channel mode.

k -> kHz, * -> no function

CONNECTION

NOTES REGARDING CONNECTION:

• Before performing connections, be sure that the power plug is removed from the AC socket, or that the POWER switch is turned off.
• When making connections, be sure to connect the "IN", "OUT" terminals correctly.
• Be sure to insert plugs securely. Poorly connected plugs can cause noise.

CONNECTION WITH VCR

Connection between the Neuro-Corder and the VCR should be made as follows:

OPERATING PROCEDURES

RECORDING CONSIDERATIONS:

• Recording cannot be made on video cassette tapes on which accidental erasure prevention tabs have been broken out. For details, see the operating instructions for your VCR.
• Since the NEURO-CORDER incorporates special circuitry, when the NTSC format VCR is used, even when the VCR's video recording time is set to the "Extended Play Mode" for recording, playback with no data deterioration can be performed. However, you sho uld be aware that tapes recorded with the "Extended Play Mode" on other PCM recorders may be impossible to play back.
• Depending on the VCR used, video cassette tapes recorded on the "Extended Play Mode" may produce no signals when played back on other VCRs. When you wish to play back a NEURO-CORDER data-recorded video cassette tape on another VCR, we recommend that you use the "Standard Mode" during recording.
  
  Also, depending on the VCR, NEURO-CORDER record/playback may be impossible. In this case as well, record on the "Standard Mode".
• When recording on the NEURO-CORDER, be sure to set the VCR's input selector switch to the "external input" or "Aux" position.

RECORDING:

1. Turn on the power to each of the devices in use.
2. Set the unit's RECORD/PLAY selector switch to "RECORD". The RECORD indicator will light.
3. Insert a video cassette tape in the VCR.
4. Select right input full scale range.
5. When recording on the VCR is begun, the NEURO-CORDER recording is begun.
6. When you complete the data recording, press the VCR's stop switch.

PLAYBACK:

1. Turn on the power to the various devices in use.
2. Set the RECORD/PLAY selector switch to "PLAY".
3. Insert a recorded video cassette tape into the VCR.
4. When playback is begun on the VCR, NEURO-CORDER playback will begin.
5. When you complete playback, press the VCR's stop switch.

• When using a VCR with a picture sharpness adjustment control, depending on the adjustment position of the control, you may experience noise or interruption of data output during playback. In such cases, adjust the control to achieve the best possible playback.

VCR TRACKING ADJUSTMENT:

In the same way as when performing picture playback, if there is a VCR tracking error, good NEURO-CORDER playback cannot be achieved. When the same VCR is used for recording and playback, there is generally little problem, but in other cases, dropout, etc., may be increased. In order to achieve the best possible NEURO-CORDER playback, perform VCR tracking adjustment in the following steps:

1. Begin playback.
2. Turn the VCR's tracking adjustment control slowly to left and right, adjusting so that the tracking error light is off.

• If a satisfactory playback cannot be achieved even after adjusting the VCR's tracking adjustment control, it may be the result of dirty heads on the VCR, or it may require replacing the tape with a new one.

TRIGGER IN/OUT:

If one were to use the audio track to record a synchronizing trigger, there is potential instability of approximately 5 msec depending upon the particular VCR. In order to overcome these shortcomings, Neuro Data has made provision for recording a trig ger pulse in the video track along with the data channels by "stealing" one sample from Channel One. (This is similar to the circuitry available in our Model DR 484.) The trigger input is a positive-going pulse. The timing uncertainty between trigger-in and trigger-out is a maximum of 22usec. If great accuracy is required, it is suggested that one use the trigger-out of the DR 890 to synchronize all other equipment.

AUDIO MONITOR:

During recording if you experience microphone oscillation, please turn down speaker volume.

COMPUTER INTERFACE:

This unit has a built-in computer 1/0 connector. To interface an IBM- AT, an interface card, At-DIO-32F is needed in your IBM-AT computer. To interface a Macintosh, interface card NB-DIO-32F is needed in your Macintosh computer. For further information on the I/O pin connector, please contact us.

Phone: (717)424-5701 Fax: (717)424-5630 Sales information Support Information sales@cygnustech.com support@cygnustech.com Mailing Address: PO Box 219 Delaware Water Gap,PA 18327

All pages contained within are Copyright of Cygnus Technology, 1997 Last Modified 02/19/97