TEL: 800-235-6960
FAX: 714-979-3355

Santa Ana, California. FM SYSTEMS, INC. has invented a new video processing device that automatically corrects video Sync and White level, Color Burst amplitude, low frequency distortion, and also clamps out up to two Volts of 60Hz ground loop interference. The VM771 VIDEO MASTER accepts, stabilizes and corrects input video signals in the range between 0.5 Volts and 2.0 Volts peak-to-peak. Within this input level range the VIDEO MASTER will automatically establish these parameters at the output of the VM771:

1. Sync level is automatically gain-regulated to 40 IRE Units.

2. White level is automatically gain-regulated so as not to exceed 100 IRE Units (but still permits a fade to Black). White level is not clipped, but retains a linear gray scale.

3. Output video level is regulated to 1 volt peak-to-peak (at 100% White level).

4. Luminance-to-Chrominance ratio is automatically corrected, thus compensating for cable slope loss or other sources of high frequency attenuation.

5. Back Porch Clamping eliminates all incoming low frequency interference such as 60 cycle ground loops, even when the video signal is removed!

6. All low frequency distortion caused by loss of DC continuity in the transmission path is cancelled out by the DC restoration systems in the VM771.

The VM771 insures constancy of video levels, automatic high frequency equalization, automatic DC restoration, and cancellation of 60Hz ground loop interference in any system where these parameters can be expected to vary over time such as:

1. Switching between satellite transponders.

2. Output of video tape machines where various recording levels may be encountered.

3. Switching between program sources.

4. Variable length cable runs such as experienced in the field at News and Sports events that cause unknown loss of high frequency response.

5. Intermittent and variable power line ground loop interference.

Since all Sync and White level control is accomplished through amplifier gain changes rather than compression or clipping of the video signal, no differential gain is introduced by the VIDEO MASTER. Linearity of the grey scale will not change through the control action of the VM771.

The automatic frequency response system of the VM771 will correct up to 10 dB or more of 4.2 MHz cable loss. This equates to automatic cable equalization for zero to 2000 feet of RG59U type cable.

The VM771 is fully shielded in a 3″ by 2″ by 6″ cast aluminum case that can abe attached to the mounting rails at the rear of an equipment rack, thus providing automatic video control without occupying any front panel rack space. This product is available from stock at an introductory price of $ 285.00 from FM SYSTEMS, INC. at 3877 South Main Street in Santa Ana, Ca 92707. Call 1-800-235-6960 or 1-714-979-3355.

If you liked this, Click here and sign up for our free monthly newsletter with helpful tips and other articles that you will also like.