Differential color signal connections

[laser_freak]

I am using the flexmod P3 which does not have differential modulation inputs. Should R-, G-, and B- be connected to the flexmods' ground (and therefor connected to each other) or is it sufficient to not connect these signals and instead only connect ILDA ground pin 25 to the flexmods' ground? If R-, G-, and B- are connected to flexmod ground, should ILDA ground pin 25 also be connected to flexmod ground?

[taggalucci]

On my FlexMod P3s, I have run separate grounds for each even though they're bridged on the board. As I am following the single-pointed grounding scheme, pin 25 is wired to that point. I believe I posted a question about this here on PL, so you're welcome to search for that if you want the answer I was given.

[laser_freak]

On my FlexMod P3s, I have run separate grounds for each even though they're bridged on the board. As I am following the single-pointed grounding scheme, pin 25 is wired to that point. I believe I posted a question about this here on PL, so you're welcome to search for that if you want the answer I was given.

Ok, so to clarify, you connect R-, B-, G-, and pin 25 all to the same point?

[megaton]

Hi

Just my 2 Cents...

I connect all(R-, B-, G-) to Pin 25 and the Flex ground all together on my PJ and work just fine.

Cheers,
Ed

[taggalucci]

Ok, so to clarify, you connect R-, B-, G-, and pin 25 all to the same point?

No. All DC power supplies ground (-v) wired to single point ground (SPG). All drivers and anything powered by DC supplies have their ground (-v) wired to SPG. All +v run direct from supplies to the units they power. Pin 25 wired to SPG. All colour signals wired directly from ILDA to drivers using dedicated wiring. Search for "single point ground" for more information and diagrams here on PL. Pangolin's site also has an explanation with diagrams.

[laser_freak]

No. All DC power supplies ground (-v) wired to single point ground (SPG). All drivers and anything powered by DC supplies have their ground (-v) wired to SPG. All +v run direct from supplies to the units they power. Pin 25 wired to SPG. All colour signals wired directly from ILDA to drivers using dedicated wiring. Search for "single point ground" for more information and diagrams here on PL. Pangolin's site also has an explanation with diagrams.

Still confused
I have read Pangolin's wiring suggestions many times and I understand the single point wiring scheme. However I am still confused by your description. Do you connect the inverted color signals (pins 18, 19, 20) to their respective flexmod's ground? In other words, pin 18 -> flexmod #1 ground, pin 19 -> flexmod #2 ground, etc. If this is not right, where do you connect the negative color signals to?

Thanks for the help

[JohnYayas]

Doesn't really matter much for laser modulation since noise in the lines will be unnoticeable by the eye.

[taggalucci]

Still confused I have read Pangolin's wiring suggestions many times and I understand the single point wiring scheme. However I am still confused by your description. Do you connect the inverted color signals (pins 18, 19, 20) to their respective flexmod's ground? In other words, pin 18 -> flexmod #1 ground, pin 19 -> flexmod #2 ground, etc. If this is not right, where do you connect the negative color signals to?Thanks for the help

In this case think of the -v (inverted) as ground. Because the FlexMod P3s don't have independent grounds for the colour signal and power supply, I suggest running two wires from that point: 1 to the SPG and 1 to the ILDA -v colour signal pin (as you described).