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Discussion Starter · #1 ·
I have a 40' S-video cable to my Sony VW10HT (with a new lamp) and a 120" Grayhawk screen and my image is not as bright as I would like.


I'm curious about the effect of boosting the signal to the projector. I assume there is some loss over a good quality 40' cable.


Is it practical to put a s-video amp in this line to improve the signal level and get good results, in other words is this a good or bad idea?


I recall that many years ago I got good results with a Kloss Novabeam CRT projector and a video amp.



Thanks for any input.
 

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I found that if I used a couple of 10m packaged S-Video cables connected togather with a coupler, my picture was dim - the small diameter coax is very high loss. I solved the problem with two 50' lengths of quad-shielded RG6 and S-video breakouts at each end. The RG6 is low-loss cable, the only drawback is it's a little bulky. If you inadvertantly swap Chroma and Luma signals, it won't work, but it won't damage anything either.


Gary
 

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Tom,


Do what Garry suggests. S-video cables are inherently compromised with their dinky carriers and the break-out to 2 runs of 75 ohm RG-6 coax and back again at the other end is THE way to do it.


Gary, where did you get your break-out adaptors and how much did they cost? I saw some MIT ones for $100 for a pair of break-out adaptor ends.


-dave
 

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Another alternative is to use a cable compensator such as the ones listed at Tributaries (select Video Electronics, then Next). I have the SA 1.3 which worked well for me for a 30' run over standard S cable to a Mitsu 52" NTSC RPTV (obtained a spool and connectors from RS). I don't use it anymore because I switched to component/RGB into a VT540, so I might be convinced to sell it.
 

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David,


I made S-Video breakout cables for less than $15 each, using Radio Shack parts. I first bought a pair of the RS gold solder cup S-Video connectors, then two of the 3' small diameter 75-ohm coax cables with push-on gold F-connectors. Then I cut each 3' cable in half and pushed the cut ends through a rubber grommet in the side of one of those 3X2X1 RS plastic project boxes. On the opposite side of the box I mounted two gold F connector double-female barrels, pushed the cables on inside the box, and screwed the box closed. I then soldered the RS S-Video connectors onto the two small-diameter cable ends, To connect the two "breakouts", I used pre-terminated RG6 50' cables with gold male F-connectors at each end. Total cost for my 50' S-Video run was $60, and the picture quality is great.


TIP: There is a lot of cheap RG6 around which should NOT be used in a video application. Look for quad-shielded cable with a solid copper center conductor, not copper-plated steel. I found 50' pre-packaged RG6 cables in the Magnavox brand name at a local Orchard Supply Hardware for $14.99 each. They had soft copper centers and double mylar shield covered with braided copper mesh covered with another layer of mylar shield. Do not mistake these for the less expensive RG59 (smaller diameter, single shield, copper plated steel center) which is OK for RF, but not video.


Gary
 

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A 40-foot cable run is should be no challenge when using a high quality coax cable. You may want to consider checking pricing and lengths with a high quality, reputable cable manufacturer. The time you spend in research may be less than building your own cable.
 
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