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Message ID: 3950     Entry time: Thu Nov 18 17:42:20 2010
Author: Joonho Lee 
Type: Summary 
Category: Electronics 
Subject: CCD cables. 

I finished the direct measurement of cable impedances.

Moreover, I wrote the cable replacement plan.

The reason I am checking the cables is for replacing the cables with impedance of 50 or 52 ohm by those with impedance of 75 ohm.

After I figures out which cable has not proper impedance, I will make new cables and substitute them in order to match the impedance, which would lead to better VIDEO signal.

Moreover, as Koji suggested, the VIDEO system will be upgraded for better interface.


I measured the cable impedance by checking the reflection ratio at the point connected to the terminator with 50 ohm or 75 ohm.

The orange colored cables are measured to be 75ohm so we do not need to replace them.

Combining the list of cable types and the list of desired length,

I need to make total 37 cables and to remove 10 cables from the current connection.

Detailed plan is attached below.

I currently ordered additional cables and BNC plugs.


From now on, I will keep making CCD cables for VIDEO upgrade.

Then, with your helps, we will replace the CCD cables.


In my opinion, I will finish VIDEO upgrade by this year.

Attachment 1: Upgrade_plan_(Nov18).pdf  34 kB  | Hide | Hide all
Upgrade_plan_(Nov18).pdf Upgrade_plan_(Nov18).pdf
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