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Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => SR Forum Archives => Pro AV FUD Forum Archive => Topic started by: Gerry Seymour on September 05, 2010, 12:29:01 am

Title: Inexpensive VGA switch?
Post by: Gerry Seymour on September 05, 2010, 12:29:01 am
I have an application where I need an inexpensive VGA switch. I have one I'm using now, but it cuts signal when it switches, so projectors go to their default screen and search for inputs again. Is there a sub-$100 switch that can handle 3 or more inputs (to a single output), that won't cut the signal when I switch?

Application: projection - several computers connected to a single projector, to allow me to switch between videos/presentations seamlessly.
Title: Re: Inexpensive VGA switch?
Post by: Brad Weber on September 05, 2010, 10:39:36 am
The only way to keep a projector from needing to resync when switching sources is to make sure it sees a constant sync signal, which pretty much means some type of switcher/scaler or seamless switcher.  Unfortunately, devices like that, and especially those that can support a minimum of three VGA/RGBHV inputs, cost significantly more than $100.
Title: Re: Inexpensive VGA switch?
Post by: Jonathan Kok on September 05, 2010, 11:32:11 am
Brad Weber wrote on Sun, 05 September 2010 09:39

The only way to keep a projector from needing to resync when switching sources is to make sure it sees a constant sync signal, which pretty much means some type of switcher/scaler or seamless switcher.  Unfortunately, devices like that, and especially those that can support a minimum of three VGA/RGBHV inputs, cost significantly more than $100.

+1.

If all of your devices output the exact same resolution, that will reduce the hunting the projector has to do...but the only way to eliminate it is to get a seamless scaler/switcher.
Title: Re: Inexpensive VGA switch?
Post by: Ken Freeman on September 05, 2010, 06:50:33 pm
Yes it does.  This is a result of loss of sync. No they are not as cheap as a switch, or doing it in the projector.   The use of a scaler (Extron 1508 for example) is the way around this.  However, many scalars also have audio features so if you are clever, you can get your new box to play double duty as an audio and video switcher, thereby softening the impact of spending more.  

The other challenge you will have is a decent scalar will not degrade the image much.  A cheap one will.  You have to decide which compromise is a bigger challenge for the end client"  The glitch as the projector re-syncs or the poor image quality of an inexpensive scalar. I suggest looking at a few before deciding. The Extron 1508 I mentioned above is a good general purpose unit that make for a great benchmark.

Ken
Title: Re: Inexpensive VGA switch?
Post by: Brad Weber on September 05, 2010, 11:10:27 pm
The IN1508 is a nice unit, however it has only two VGA inputs (along with two composite video, two Y/C, one component video and one DVI-D) and seems to be going for around $1,100 to $1,400.  The three VGA input requirement actually seems to exclude many units and any switcher/scaler with three or four VGA inputs is going to be way more than $100.
Title: Re: Inexpensive VGA switch?
Post by: Ken Freeman on September 06, 2010, 01:04:44 am
Brad Weber wrote on Sun, 05 September 2010 20:10

The IN1508 is a nice unit, however it has only two VGA inputs (along with two composite video, two Y/C, one component video and one DVI-D) and seems to be going for around $1,100 to $1,400.  The three VGA input requirement actually seems to exclude many units and any switcher/scaler with three or four VGA inputs is going to be way more than $100.


Good points as always Brad.  I have a few of our smaller breakout room packages built around these and use a MAC with DVI as the third machine. At first I thought that the DVI had the analog pins, but it appears not.  DVD , PTZ cameras and others always seem to show up and fill the other holes.  It is a great swiss army piece with costing a ton.  I wish they would add SDI to it.

Ken