Vga splitter: how?

Discussion about displays and related hardware including MiSTer filters and video settings.
AmintaMister
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Vga splitter: how?

Unread post by AmintaMister »

Hi!

I want to "split" the video signal of Mister coming to Vga to Start to multiple CRT monitors (1 PVM, 1 Philips and 1 Pc CRT monitor) I own.

So I've bought on Amazon this Vga splitter (https://www.amazon.it/gp/product/B01F37AVWQ/) but the quality of the final video is HORRIBLE!

Maybe I need a switcher instead of splitter? Meaning that, thorough a button, the signal come out only to a monitor at a time?

If yes, can you point me out a link?

Thanks in advance!
FoxbatStargazer
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Re: Vga splitter: how?

Unread post by FoxbatStargazer »

An unpowered analog splitter is asking for trouble, yes. You're only going to get half the signal power to each output. Only switchers will deliver acceptable picture without power.

If you have an analog I/O board then keep in mind you have two video outputs, an analog VGA port and a digital HDMI. You can get an HDMI->analog converter and use the HDMI port for a second display. You can use direct_video to get that original analog signal out of the HDMI side.

Also keep in mind that certainly the phillips and VGA monitor require different resolutions, 15 vs 31 khz. No analog splitter could deliver a useful image to both at the same time. (Not sure if your PVM is multisync.) You could output 15 khz from the VGA port to your TV, and 31+ khz from the HDMI port using the scaler, then an HDMI to VGA converter, and connect that to your VGA monitor. This lets you output different resolutions from the Mister at the same time.
callanabrown
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Re: Vga splitter: how?

Unread post by callanabrown »

You should buy a powered splitter, these days they will have a usb port for power. They work great for 15 kHz and 31 kHz in my experience. Of course your target monitors will all have to support the single resolution being output from the source.

I use a ugreen splitter from Amazon.
AmintaMister
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Re: Vga splitter: how?

Unread post by AmintaMister »

callanabrown wrote: Mon Oct 04, 2021 12:42 pm You should buy a powered splitter, these days they will have a usb port for power. They work great for 15 kHz and 31 kHz in my experience. Of course your target monitors will all have to support the single resolution being output from the source.

I use a ugreen splitter from Amazon.
As you can see from link I’ve posted, my splitter is a powered ugreen bought from Amazon.
AmintaMister
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Re: Vga splitter: how?

Unread post by AmintaMister »

FoxbatStargazer wrote: Mon Oct 04, 2021 12:12 pm An unpowered analog splitter is asking for trouble, yes. You're only going to get half the signal power to each output. Only switchers will deliver acceptable picture without power.

If you have an analog I/O board then keep in mind you have two video outputs, an analog VGA port and a digital HDMI. You can get an HDMI->analog converter and use the HDMI port for a second display. You can use direct_video to get that original analog signal out of the HDMI side.

Also keep in mind that certainly the phillips and VGA monitor require different resolutions, 15 vs 31 khz. No analog splitter could deliver a useful image to both at the same time. (Not sure if your PVM is multisync.) You could output 15 khz from the VGA port to your TV, and 31+ khz from the HDMI port using the scaler, then an HDMI to VGA converter, and connect that to your VGA monitor. This lets you output different resolutions from the Mister at the same time.
I’ve a powered one and the quality is orribile. Thanks for the explanation. What about a SWITCHER? I can find only vga switcher from multiple devices to one monitor. I need the opposite one.
callanabrown
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Re: Vga splitter: how?

Unread post by callanabrown »

Oops sorry. I saw the other comment that using a passive one would be bad.

Here's my video where I use it, granted I'm actually using it for duplicating 15 kHz in this particular video.

https://youtu.be/ZgRqo-lWLh8?t=510

Good colors, brightness and everything when I used it.
FoxbatStargazer
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Re: Vga splitter: how?

Unread post by FoxbatStargazer »

AmintaMister wrote: Mon Oct 04, 2021 1:06 pm What about a SWITCHER? I can find only vga switcher from multiple devices to one monitor. I need the opposite one.
If it's truly unpowered and dumb (mechanical), it will work in either direction. Mine sure does, although Amazon doesn't seem to sell it anymore.
AmintaMister
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Re: Vga splitter: how?

Unread post by AmintaMister »

Ok, at the end I've bought this Vga mechanical splitter and it works perfectly! https://www.amazon.it/gp/product/B07NVP ... UTF8&psc=1
thorr
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Re: Vga splitter: how?

Unread post by thorr »

I am using a couple of these: https://www.amazon.com/gp/product/B01LY1FZ8K/
I have component video running through one and audio running through the other. Out and In labels are opposite of what I am using them for.
d909
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Re: Vga splitter: how?

Unread post by d909 »

My Extron Crosspoint switch works flawlessly with zero quality loss that I can see. They're very powerful and useful analog video switches. They're not actually VGA though - they're BNC - but VGA to BNC cables work great.

They can route any combination of inputs to any combination of outputs. You can even loop one of the outputs through a processor of some kind, back in to another input, and then route that input to yet another output, etc. For example, I've taken a playstation 2's RGB output, routed in to the crosspoint and then out to: 1. a 15khz CRT 2. A framemeister scaler to convert to 31khz and then back in to the crosspoint. That second input is then routed to a couple different 31khz CRTs.
Swainy
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Re: Vga splitter: how?

Unread post by Swainy »

I use this old style VGA switch box and it works perfectly.

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AdGOiyb.jpg (285.36 KiB) Viewed 1 time

https://www.ebay.co.uk/itm/384104682786

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43JB2xE.jpg (411.65 KiB) Viewed 1 time
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