Using a Splitter for S-Video

[Seeker47]

Is this a bad idea ? If so, why ? (Signal attenuation ?) If not necessarily a bad idea, does it make much difference which brand of splitter I get ?

[davideck]

Video sources expect to be terminated at 75 ohms at one destination.
Splitting one source to two destinations results in a 37.5 ohm termination; not a good idea.
Any video splitter would therefore need to be active...

[Seeker47]

Video sources expect to be terminated at 75 ohms at one destination.
Splitting one source to two destinations results in a 37.5 ohm termination; not a good idea.
Any video splitter would therefore need to be active...

Does active mean that it must be powered, must have some sort of signal amplifier, or both ? What are some active splitters you would recommend (particularly for S-Video), what do they cost, and where do you buy them ?

[davideck]

Both. Active splitters are actually called Distribution Amplifiers.
Radio Shack sells one with S-Video...
http://www.radioshack.com/product/index.jsp?productId=2103065&cp=2032057.2032187.20321...entPage=family

[edDV]

Here ya go
http://www.cablestogo.com/product.asp?cat%5Fid=3104&sku=41064&engine=adwords !654&keyword=%28s+video+distribution+amp%29
http://www.autopatch.com/series_d_a/completeinfo.html
http://www.trianglecables.com/svideo-amp.html

Better price
http://www.studio1productions.com/distribution_amps.htm
http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=930278&sku=C184-41064

[Seeker47]

Here ya go
http://www.cablestogo.com/product.asp?cat%5Fid=3104&sku=41064&engine=adwords !654&keyword=%28s+video+distribution+amp%29
http://www.autopatch.com/series_d_a/completeinfo.html
http://www.trianglecables.com/svideo-amp.html

Better price
http://www.studio1productions.com/distribution_amps.htm
http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=930278&sku=C184-41064

Thanks much for the links, edDV. Before I go purchase anything though, I'd like to be sure we are talking about the same circumstances, and that they are applicable.

I am NOT sending the same signal to multiple devices (like 2 or more monitors) at the same time. In my home setup, which is utilitarian and nothing fancy, I have a digital cable connection that is split initially by a plain old cable-company-installed splitter. This is so that the tv won't be totally dependent for a signal on any other device. The sacrifice there is NO premium channels, no 3-digit channels, as these would require the cable box -- but I find that an acceptable compromise. The other half of the split goes to the digital cable box. (Possibly you will tell me this is a mistake *already*, due to a deficiency of ohms, but I find the results to be reasonably good -- bearing in mind that the display device is a 27" CRT.) The cable box then feeds the Pioneer recorder. It and a dvd player plus a vcr have their signals routed to the tv by a Sima SVS4 switcher, because 2 of those 3 devices can take advantage of S-video connections, and because the tv has limited inputs: an either / or choice between one S-video or 3 composite inputs. If the S-video is used, the composites are deactivated, or vice-versa.

It seems to me from quickly looking over those links that there may be some overlap between what the proc amp / active splitters do and what the Sima switcher does ? In another thread on video switches a while back, someone asked me if I noticed any "bloom" effect from the SVS4. Actually I don't. That may have something to do with the age and quality of the JVC AV-series tv, but I've been rather satisfied with this arrangenment, and don't plan any major changes, probably until drastic upgrades become necessary for the advent of mandatory HD service.

In any case, what prompted my splitter question in the first place was an upcoming installation for relatives. At their place, they have both satellite and cable connections coming into the room, and like to be able to use either at will. Their cable service does not make use of a cable box, but their satelite connection does come in through a satellite box. The satellite box has some extra outputs, including an S-Video one. This all happens right now via separate connections into an LCD tv. I will be adding a DVR to that mix, which should be able to record from one or both sources, and I want to be able to maintain the kind of signal-source flexibility they already enjoy. (The DVR has a good selection of inputs.) At the same time, I DON'T want either feed to the tv to be dependent on the DVR being turned ON. They are not technically inclined, so I'd like this to be as transparent and not-in-their-way as possible. So, are we still talking about a job for one of these active splitters, or are there other equally acceptable solutions ?

I do have a spare SVS4 in storage. That unit offers auto-sensing / switching, which would probably cover the hands-off transparency part. This is going to be a a non-HD setup, so S-video connections should be good enough.

[edDV]

Thanks much for the links, edDV. Before I go purchase anything though, I'd like to be sure we are talking about the same circumstances, and that they are applicable.

I am NOT sending the same signal to multiple devices (like 2 or more monitors) at the same time. In my home setup, which is utilitarian and nothing fancy, I have a digital cable connection that is split initially by a plain old cable-company-installed splitter. This is so that the tv won't be totally dependent for a signal on any other device. The sacrifice there is NO premium channels, no 3-digit channels, as these would require the cable box -- but I find that an acceptable compromise. The other half of the split goes to the digital cable box. (Possibly you will tell me this is a mistake *already*, due to a deficiency of ohms, but I find the results to be reasonably good -- bearing in mind that the display device is a 27" CRT.)

Not a problem splitting the cable RF connection. Each split reduces amplitude but does not impair impedence (or frequency response). The cable box, VCR, DVD recorder, TV, etc have RF AGC (automatic gain control) to adjust for levels over a wide range.

The cable box then feeds the Pioneer recorder. It and a dvd player plus a vcr have their signals routed to the tv by a Sima SVS4 switcher, because 2 of those 3 devices can take advantage of S-video connections, and because the tv has limited inputs: an either / or choice between one S-video or 3 composite inputs. If the S-video is used, the composites are deactivated, or vice-versa.

That is fine. S-Video can be switched but not split.

It seems to me from quickly looking over those links that there may be some overlap between what the proc amp / active splitters do and what the Sima switcher does ? In another thread on video switches a while back, someone asked me if I noticed any "bloom" effect from the SVS4. Actually I don't. That may have something to do with the age and quality of the JVC AV-series tv, but I've been rather satisfied with this arrangenment, and don't plan any major changes, probably until drastic upgrades become necessary for the advent of mandatory HD service.

If the Sima SVS4 is being used to switch S-Video inputs the above holds. I'll look at its other modes but for now, it does AGC (automatic gine control) on audio which can be a good or bad thing.

In any case, what prompted my splitter question in the first place was an upcoming installation for relatives. At their place, they have both satellite and cable connections coming into the room, and like to be able to use either at will. Their cable service does not make use of a cable box, but their satelite connection does come in through a satellite box. The satellite box has some extra outputs, including an S-Video one. This all happens right now via separate connections into an LCD tv. I will be adding a DVR to that mix, which should be able to record from one or both sources, and I want to be able to maintain the kind of signal-source flexibility they already enjoy. (The DVR has a good selection of inputs.) At the same time, I DON'T want either feed to the tv to be dependent on the DVR being turned ON. They are not technically inclined, so I'd like this to be as transparent and not-in-their-way as possible. So, are we still talking about a job for one of these active splitters, or are there other equally acceptable solutions ?

I do have a spare SVS4 in storage. That unit offers auto-sensing / switching, which would probably cover the hands-off transparency part. This is going to be a a non-HD setup, so S-video connections should be good enough.

OK, cable feeds LCD RF input (this can be split to DVDR). Sat Box feeds S-Video and audio to TV. You want this repeated to the DVDR? Would feeding the composite feed to the LCD and S-Video to the recorder work? Otherwise you need a S-Video/audio DA at this point. I'll look at the Sima SVS4 to see if it can function as DA.

[edDV]

The SVS4 will not work as a DA from what I can tell. For others a simple S-Video switch is available from Philips or RCA.
http://store.yahoo.com/shoptronics/rcaauvisoses.html

You have a choice of feeding the sat box composite to one (LCD or DVDR) and S-Video to the other. Or if would want S-Video to both, you need a DA.

If the LCD monitor is short on S-Video inputs, you can use the SVS4 to switch between the Sat box and DVDR. The "auto sense" feature would switch to the Sat box when teh DVDR is off.

[Seeker47]

If the Sima SVS4 is being used to switch S-Video inputs the above holds. I'll look at its other modes but for now, it does AGC (automatic gine control) on audio which can be a good or bad thing.

I normally leave the AGC turned Off.

OK, cable feeds LCD RF input (this can be split to DVDR). Sat Box feeds S-Video and audio to TV. You want this repeated to the DVDR?

Probably.

Would feeding the composite feed to the LCD and S-Video to the recorder work?

I think so. Can only be sure when I get there, in another couple weeks.

Otherwise you need a S-Video/audio DA at this point. I'll look at the Sima SVS4 to see if it can function as DA.

Thanks so much for your help.

[Seeker47]

The SVS4 will not work as a DA from what I can tell. For others a simple S-Video switch is available from Philips or RCA.
http://store.yahoo.com/shoptronics/rcaauvisoses.html

I read the description at this link, and did not see any mention of DA capability . . . or perhaps I misunderstood you. I did check out the Radio Shack and other DA links.

You have a choice of feeding the sat box composite to one (LCD or DVDR) and S-Video to the other. Or if would want S-Video to both, you need a DA.

If the LCD monitor is short on S-Video inputs, you can use the SVS4 to switch between the Sat box and DVDR. The "auto sense" feature would switch to the Sat box when teh DVDR is off.

Another thing: Is S-Video synonymous with S-VHS, in terms of cabling ? There was a spare "S-VHS" cable that came with my Pioneer 520. It looks quite similar to an S-Video cable, but not identical.

I won't be at this location until next week, but I have printed out this thread for reference, and will get back to you in the event of any further questions. In the meantime, they sent me the connection diagram pages from the manual of this LCD tv. It has AV-1 and AV-2 inputs. One of these is component, the other a dual S-Video | Composite connection (which are mutually exclusive: one must choose which video connection to use for that input). I think I'm going to try to do this with just the Sima SVS4 somehow, since I don't want to add one more box to this setup than is absolutely necessary.

[edDV]

Just feed the sat box composite output to one (LCD or DVD recorder, your choice) and S-video to the other. Audio may still need a DA. Here's one.

http://www.radioshack.com/product/index.jsp?productId=2103065&cp=&kw=audio+distributio...entPage=search

[Seeker47]

Just feed the sat box composite output to one (LCD or DVD recorder, your choice) and S-video to the other. Audio may still need a DA.

First of all, Thanks to edDV and others for all your help so far.

Sorry to bother you again, but I'm finally where the install is to be done, and the situation is not quite as I expected it to be. (I'm going to try to attach a diagram of how the Direct TV guy did his installation.) As you will see -- if my crude diagram comes through * -- he routed the cable signal in through the Ant. connection, which I'm guessing is how he was able to have only ONE audio connection going in for both satellite and cable. (And there is a 2nd. set of audio OUTs available from the Sat box, for whatever that may be worth.)

{ * Ooops, never mind. I see that the .JPG I scanned weighs in at 687K, whereas the forum attachment limit is 150K. Perhaps I can send it to you as a personal mail attachment. I would have done the whole message that way, but I thought it possible some one else reading this might benefit from it. }

As far as possibly making use of the Sima SVS-4, it doesn't handle coax or component, just S-Vid or RCA -- so that might not work out. I think it may be difficult or impossible to achieve all of the factors I was looking for:
1. Independent connection -- DVR need not be on to watch a
program.
2. Full flexibility -- record from Cable or Sat.
3. As transparent to user as possible, minimal input switching.

This might be easier if the DVR had a passive pass-through output, which did not require it's being turned on, but I doubt there is such a thing on any of them, even those generously equipped for inputs & outputs.

I'm wondering if I can use another splitter after the first one, for the cable signal only ? If that's o.k., it would provide device independence for the cable portion. Then maybe the Sima could take care of the S-Vid for the satellite. Unless the auto-switching is going to get confused, figuring that one or the other (DVR or LCD) is always getting signal. Not sure where that would leave matters for the sound, but I'm pretty sure I don't want to mess with a DA. That would be one connection piece too many, I think. We're already pushing things on how complicated this setup is going to be.

The AV-IN/2 side is totally unused at the moment. It looks to me that the top (RCA) portion of it is strictly a TV OUT, which can be enabled via defaults set in the LCD. There is no Component OUT from the Sat box. So, I don't see any salvation on the AV2 side.

I'm probably missing a few things here, but it is looking to me like I will have to compromise on items 1 & 3: Some of this is probably going to have to go through the DVR, which will have to be ON for non-recording Viewing purposes. And I guess that's how I'll rig it, unless some better idea comes along.

[lordsmurf]

I would never split s-video.

[edDV]

I asked him to email his drawing to me so I can post it.

[edDV]

Here is Seeker47's drawing.



I'll look it over and comment tomorrow.