Is this AC Ripple or Normal?

r27blades

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Hi Folks,

Appreciate you reading. I have converted over a Nova Blast cab into a more traditional candy cab with a dedicated PSU for the Jamma and introduced a power strip to feed my monitor and several USB-powered items. The power supply I am using is a 5V/10A attenuated PSU I bought from Amazon (link).

I didn't really notice the ripple until I got my new monitor. It is an Arcooda 4:3 Ratio Arcade LCD Monitor 15khz 24khz 31khz up to 2880x2160. After testing the monitor with other sources and reconnecting the old monitor, and confirming it is there but less pronounced, I went back to reviewing my setup. I figured the issue is between the PSU and the Mini Gun. I started reading about earth grounding and the importance for older monitors.

My PSU does have an earth ground port, which I have tied to the green wire in my power cable. I thought that would handle any grounding needs. Do I need to tap off of that port and ground to the inside of the cabinet, too? Also, this is present on a new LED arcade monitor with its own power supply plugged into a surge protector. It doesn't exactly mirror the described smoking gun scenario. If I am getting AC ripple, can I ground the supply, or would I need to replace it? Or is this just want I should see and I didn’t notice in the past playing on CRTs? I attached some photos.

In case anyone is curious, I took two videos, one showing SSF2X and another using my laptop when connected to the monitor. Sending a video into the monitor not tied to the PSU or jamma setup passes fine. Through Jamma, I seem to have some interference unless I am just mistaken, and that is normal?

In the case of SSF2X the connections are PSU > JAMMA harness > SSF2X > JAMMA harness > Mini Gun > RetroTink 4K Pro > Arcooda Monitor
In the case of the laptop, the connections are Laptop > Arcooda Monitor

SSF2X Video

Laptop Test Screen Video

Thanks in advance!
 

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You may wana bridge ground on dc side and ground on ac side of your power supply
Thanks for sharing this! Okay, so would I bridge them or tied out to a grounding spot in the cabinet?

If I am doing a grounding spot, I would need to create one… any guidance there?

And sorry last one, does that look normal, or does it seem to be some kind of interference from your perspective?
 
Last edited:
I had same problem in my setup and bridging DC ground and AC ground completely resolved it

You can read it here
 
I had same problem in my setup and bridging DC ground and AC ground completely resolved it

You can read it here
That’s amazing! OK I will try that this evening. What gauge do you recommend? Assuming AWG 18 would be fine?
 
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