VGa to Video

[WolvesAndi]

Need a VGA to Video down scaler, looked in the usual places and couldnt find one, can find it the other way round, anybody any ideas? Need it pretty fast in the midlands.

 

Cheers

 

Andi

[david.elsbury]

Try the phrase "scan converter" rather than "scaler" and that might help.

Is this to buy or hire?

[Peter F]

If you need it really fast (i.e. today) then Maplins do one for about 30 pounds.

They call it a PC to TV converter.

Here is one.

 

Cheers,

 

Peter

[WolvesAndi]

thats what I need, buts its USB powered, got to rig it on a truss, any other suggestions ? sorry to be a pain

[billy jim]

Change your cabling- have the scan converter near the pc and then run BNC or similar to the truss, rather than running VGA to the truss and then a short run of BNC?

Obviously would depend on what cable you have to hand...

[Tom Baldwin]

Or, if you don't have the necessary video cabling available, add one of these and run hard power up to the truss

[Peter F]

Or, if you don't have the necessary video cabling available, add one of these and run hard power up to the truss

 

A quick look at the manual seems to indicate that the power input for the unit is a pretty standard looking socket. Any old 5V DC power supply with the right size plug on it should do the job if you don't have a usb based power supply kicking around (Blackberry charger perhaps?)

 

What is your VGA source?

Have you checked there isn't a s-video output on it already? Most laptops have one and the quality of them is generally pretty good. Don't be fooled by the odd number of pins, a standard s-video lead will fit and work.

 

If it's an Apple without an s-video output you can buy a DVI to S-Video adapter.

 

If your projector doesn't have an s-video input you can buy s-video to composite converters for about a quid.

 

Cheers,

 

Peter

[WolvesAndi]

ok all, I got the converter from maplins, but it didnt work, it only works on the resolutions of640x80, 800x600, 1024x768, and I have a free sat bow that outputs to 576p, 720p, 1080i. I'm converting the hdmi to VGA through one of theese

 

http://cpc.farnell.com/jsp/level5/module.j...=cpc/512116.xml

 

I can get the signal to the projector through the VGA, but there robe digispots and if you go in on the vga you cant use the graphics engine, so you need to go in on either the s-video or component.

 

All the cable is installed so running new cable is a nightmre through a dozen walls and lengthy routes

.

 

Any ideas?

 

Cheers

 

Andi

[Ynot]

If it's composite input (not Ypbr) then what about one of these.

We have a couple in house - useful little boxes.

 

VGA in/out and a BNC composite out as well.

 

Ah - hang on - that only does the same resolution as above...

Hmm...

[WolvesAndi]

If it's composite input (not Ypbr) then what about one of these.

We have a couple in house - useful little boxes.

 

VGA in/out and a BNC composite out as well.

 

Ah - hang on - that only does the same resolution as above...

Hmm...

 

 

Yeah thats the problem it wont acept the resolutions that I'm sending to the maplins version of that

[Peter F]

Your HDMI to VGA box is outputting one of these resolutions:

VGA Resolutions

640x480 (60/72/75/85Hz)

800x600 (56/60/72/75/85Hz)

1024x768 (60/70/75/80/85Hz)

1280x1024 (60/75Hz)

 

The Maplin box will accept:

640x480 (60/72/75/85Hz)

800x600 (60/72/75/85Hz)

1024x768 (60/72/75Hz)

 

Unfortunately I can't see a manual for the CPC product, if you have one or the exact model number so I can go looking for one that would be helpful.

 

Whatever the CPC box is currently outputting is obviously not compatible with the Maplin one. Could be either resolution or frequency. If you have a way of changing either of these than that might solve your problem. Try connecting the VGA output of the CPC box to a computer monitor that helpfully displays the input settings for you when you are setting it up, then you can discover exactly what is coming out of the CPC box.

 

I assume the freesat box only has HDMI outputs?

 

Cheers,

 

Peter

[WolvesAndi]

Your HDMI to VGA box is outputting one of these resolutions:

VGA Resolutions

640x480 (60/72/75/85Hz)

800x600 (56/60/72/75/85Hz)

1024x768 (60/70/75/80/85Hz)

1280x1024 (60/75Hz)

 

The Maplin box will accept:

640x480 (60/72/75/85Hz)

800x600 (60/72/75/85Hz)

1024x768 (60/72/75Hz)

 

Unfortunately I can't see a manual for the CPC product, if you have one or the exact model number so I can go looking for one that would be helpful.

 

Whatever the CPC box is currently outputting is obviously not compatible with the Maplin one. Could be either resolution or frequency. If you have a way of changing either of these than that might solve your problem. Try connecting the VGA output of the CPC box to a computer monitor that helpfully displays the input settings for you when you are setting it up, then you can discover exactly what is coming out of the CPC box.

 

I assume the freesat box only has HDMI outputs?

 

Cheers,

 

Peter

 

The box has a scart out also, so at the free sat box I converted the composite to VGA and then sent that to the truss and converted it back to composite at the projector but the quality was bad and fuzzy, really needs another form of signal to get the quality, this also goes into a switcher and then sent over cat 5 so its converted about 4 times.

 

On the digispot I can look at the image with the vga input but it wont let you keystone it so its a little bit useless, but with the VGA its a quality image

[Tom Baldwin]

Hang on - why bother with the double conversion.

You have VGA cable running all the way to the projector - you could think of that as being five composite runs with a funny connector!

Use a HD15 - 5xBNC cable at each end, and send composite natively all the way (down only one of the five BNCs). Ought to give better picture quality than the double conversion, even if it isn't as good as sending the sync separately.

[Peter F]

The box has a scart out also, so at the free sat box I converted the composite to VGA and then sent that to the truss and converted it back to composite at the projector but the quality was bad and fuzzy, really needs another form of signal to get the quality, this also goes into a switcher and then sent over cat 5 so its converted about 4 times.

 

Oh heck (as we say oop North)

 

Too many conversions going on in that signal chain.

Composite is a fairly resilient signal until you start doing anything to it, treat it well and you can go far with it. Start putting all sorts of conversions and weird and wonderful boxes in its path and the picture will get softer and softer.

 

Tom's suggestion of using 1 line on the vga cable is a good one.

 

In theory, you could get s-video out of the scart, bodge together a splitter to use 2 lines on the vga cable, bodge something at the other end to convert 2 bnc to 1 s-video connector at the other end. You would have to be some sort of sadist to go to all this effort, the improvement in picture quality will not be worth all the messing about.

 

Composite out of your digibox to composite into your projector. Simples!

 

Assuming your switcher is a composite one, can I introduce you to a Passive Composite Split Device.. This might be useful to you. Don't use too many of them.

 

I have a terrible feeling that sometime in the next couple of days you are going to learn what video hum looks like. There is a picture here. Before you set off in the various directions that article sends you, I suggest you try possible simple solution number one.

 

Possible simple solution to video hum:

 

1. Ensure everything is sharing the same earth.

 

If it is possible to power your digibox and your projector from the same point then do it.

 

Cheers,

 

Peter

[Nick Mawer]

Looking at the price - I am guessing that there is no scaling going on inside this CPC box (nothing wrong with that BTW). Therefore if you are feeding HDMI 1080i into the box, then you are getting analogue 1080i out. You would therefore need to buy a scan converter which converts from YPrPb to Composite such as the Kramer VP-502xl http://www.kramerelectronics.co.uk/product...del.asp?pid=402

 

You are right about one thing, a double conversion is going to give you poor results. However, the quality of the machines that you use to do the conversion can have a significant impact on how good or bad the result is.