Professional broadcast

Alpha Plus

  • Works with pass-through composite or S-Video signal of PAL, SECAM and NTSC standards. Automatic activation of video signal relay bypass mode upon computer power loss.
  • YUV component and key (alpha-channel) signal outputs allow to use the card with a mixer that has component and DSK (Down Stream Key) inputs.
  • In analog mixing mode pass-through signal is not being decoded, it is carried through the card without changes, while saving all its frequency characteristics and service information.
  • In digital mixing mode the signal is decoded by the latest PHILIPS decoder with color combine filter for dividing brightness and saturation signals.
  • In digital mixing mode the number of connection combinations is unlimited. This lowers the requirements for input signal quality, while preserving the high quality of the output signal.
  • All output signals pass through active filtration and black balance anchor. Component output Green signal and key signal (alpha-channel) have built-in video synchronization with disabling option.
  • Capture and hardware scaling of video signal from card input allow to resize the pass-through video stream image in real time in combination with computer graphics overlay.


Size: 188x126 mm
Bus: PCI-Express 1x
Inputs (1,0 v / 75 Ohm):
  • Composite: PAL/SECAM/NTSC;
  • S-video: PAL, SECAM, NTSC
Outputs (1,0 v / 75 Ohm):
  • Composite: PAL/SECAM/NTSC;
  • S-video: PAL, SECAM, NTSC;
  • Component YUV;
  • Analog linear key DSK signal alpha-channel output with sync pulse (BNC)
Relay Bypass in case of power failure: CVBS, S-Video
Analog mixing bandwidth: > 10 MHz
Differential nonlinearity: < 0,2%
Alpha-channel: 256 degrees of transparency
Alpha-channel delay adjustment: from -127 up +127 ¼ pixel each
Chrominance subcarrier 
phase adjustment:
0 - 360° (256 values)
Adjustment of graphics position relative to sync signal: Within the limits of entire active line with an accuracy to one pixel.


Additional Modules 

Sound Pro v3.1 

Stream Audio extension sound card

The card sits inside the computer and connects to Alpha Plus PCI-E with a special cable, which transfers service information and relay control signal. The card provides a professional quality audio track synchronized with video. This ensures accurate sound insertion into pass-through audio channel. In addition, the card features analog and digital mixing of pass-through and played back audio streams and provides audio bypass mode at computer power cutoff.


  • 24-bit audio codec UDA1380.
  • 48kHz sampling frequency.
  • Audio in signal/noise ratio: 100 dB.
  • Audio in channel decompression: 97 dB.
  • Audio out signal/noise ratio: 68 dB.
  • Audio out channel decompression: 90 dB.


  • Balanced analog Output: TRS 1/4' Balanced out (stereo)
  • Balanced analog Input: TRS 1/4' Balanced in (stereo)
  • Audio In: Phonejack Stereo Line in (stereo)
  • Audio Out: Phonejack Stereo Line out (stereo)


Audio BYPASS extension card

This small card is placed inside the computer and connected to Stream Alpha Plus PCI-E with a special cable, which sends the relay control signal. The card provides audio bypass mode synchronous with switching on/off the similar mode for pass-through video signal, ex. at computer power cutoff.

In this Stream ALPHA Plus PCI-E card operation design the sound is transmitted through standard computer Sound Blaster. There are plenty of sound cards on the market and it is not necessary to select the most advanced model. An on-board sound card can be also used. It is important however, that the sound card has only one Line In input.

If you intend to use TELE info with an external digital video stream source (except DV - IEEE-1394), make sure that the sound card does not have combined Line In and Mic In inputs.


  • Audio In: RCA x2 Line In (stereo)
  • Audio Out: RCA x2 Line Out (stereo)
  • Sound Card In: Phonejack Stereo, connects to computer sound card Line In
  • Sound Card Out: Phonejack Stereo, connects to computer sound card Line Out
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