Table of Contents
Advertisement
BNC Cables
Poor quality BNC cables can result in lost and/or corrupted video and otherwise unreliable
operation. This problem has become more widespread with the use of 3G (3 GHz) video
throughout the industry. We therefore offer the following recommendations:
•
Always, always use 3G rated SDI cables. It's too easy to switch from 1.5G dual link to 3G single
link and forget to switch to a better grade SDI cables. Toss out all those older 1.5G cables and
avoid all the headaches (note the supplied cables with the Gemini work great at 3G). Extra HD-
SDI 3G Rated Cables, identical to the ones included with the Gemini 4:4:4, may be ordered
from your local dealer. It is a great idea to have spares on hand.
•
Never add a "T" or chain SDI cables together. The introduction of a connector distorts the
signal quality leading to possible errors in the video.
•
Pay attention to the "Check SDI cable" message in the new firmware. This indicates that the
Gemini is detecting a CRC error in the video. A faulty cable is the most likely culprit.
Powering the Gemini
This is the most common Gemini issue, providing power with the correct voltage and polarity. As
mentioned in the SSD section, adequate power (20 W) is critical for proper operation of the
Gemini, particularly during record. So, here's a short list of recommended practices regarding
power:
•
Always double-check the polarity of the incoming power connection. Just like over-voltage,
reverse-voltage will damage the internal power protection circuit requiring a return of the
Gemini to the factory for repair. Shown below is the pin-out for the 4-pin Hirose power
connector used in the Gemini.
•
The Gemini power is rated to operate from +6V to +19V, never under any circumstances,
exceed this voltage. The Gemini power is not directly compatible with the 3-pin RS power port
from the ALEXA, which nominally outputs +24V. Likewise direct connection to a +28V battery
will cause immediate damage to the Gemini voltage input protection circuit, necessitating an
RMA return to the factory for repair.
•
Be extra careful not to plug the power in the remote receptacle, located on the opposite side
of the recorder. This will also cause a permanent failure, requiring a return to the factory for
repair.
•
Convergent Design offers a over-voltage/reverse-voltage protection module which mounts on
the side of the Gemini and plugs into the power receptacle. This power module works by
blocking the power to the Gemini 4:4:4 or nanoFlash if the voltage is over 19 Volts, or if the
www.Gemini444.com
Gemini 4:4:4 User Manual
1) Power: +6.5 ~ +19V
2) Power: +6.5 ~ +19V
3) Ground
4) Ground
Note: Positive Power must be connected to both Pins 1 & 2.
Ground must be connected to both Pins 3 & 4.
021313
62 |
P a g e
Advertisement
Table of Contents
