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SOLVED: 018-0648-001 breakout cable grounding pins - Printable Version

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SOLVED: 018-0648-001 breakout cable grounding pins - Geoman - 02-27-2020

Does somebody own a "4-way BNC Breakout Cable for RAD Audio: 65 UKP (SGI PN 018-0648-001)" to check it via multimeter??
-- even Ian does not have it, and every distributor gives me a "not in stock" quote, because I would rather buy than solder but here we go again...

One would think compared to the "LVDS-cable hell", this would be easy, because of the good documentation. BUT there are a lof of grounds. Can I / do I have to connect these ground together? Like in the graphics below? The pinout is:
Code:
1, COAXIAL DIGITAL_IN GND
2, COAXIAL DIGITAL_IN
3, VID_REF
4, VID_REF GND
5, VID_REF
6, VID_REF GND
7, NOT CONNECTED
8, CHASSIS GND
9, COAXIAL DIGITAL_OUT
10, NOT CONNECTED
11, COAXIAL DIGITAL_OUT GND
12, NOT CONNECTED
13, CHASSIS GND
14, CHASSIS GND
15, NOT CONNECTED


RE: SOLVED: 018-0648-001 breakout cable grounding pins - Geoman - 02-27-2020

I measured the pinout at the adaptor's side, and it shorts to chassis at 1,4,6,8,11,13,14 as stated above. So save to create this cable at your own.

RE: SOLVED: 018-0648-001 breakout cable grounding pins - jan-jaap - 02-27-2020

I'm sure the grounds are connected inside the digital video adapter. Probably some sort of star topology.

But I still wouldn't connect them externally, that creates ground loops. If the grounds could be connected in the cable there would have been only 1 ground pin in that D-sub connector.

RE: SOLVED: 018-0648-001 breakout cable grounding pins - Geoman - 02-27-2020

Yes that's what I planned: to ignore chassis ground alltogether and only solder 4 pairs of signal and ground to get 4 cables:
Code:
1, COAXIAL DIGITAL_IN GND
2, COAXIAL DIGITAL_IN

3, VID_REF
4, VID_REF GND

5, VID_REF
6, VID_REF GND

9, COAXIAL DIGITAL_OUT
11, COAXIAL DIGITAL_OUT GND


RE: SOLVED: 018-0648-001 breakout cable grounding pins - Geoman - 03-01-2020

What an ordeal - 40 $ of material and 4h of my time, but now I've got all the Tezro-Cables I need.
   
2, COAXIAL DIGITAL_IN is shorted to PCI-ground-pin via 76 Ohms, all the GNDs are shorted to ground via 0 Ohms i.e. the outer isolation of the coax-cable. That's the internal organization of the PCI-card.
I only soldered 8 wires as stated above.