Upgrading to HDMI

Sorry to start a new thread but I felt this warranted it. In an effort to upgrade our system to be able to send a hi-res image from a computer at the pulpit to the cultural hall and potentially webcast in a building with just coax, I purchased a Sewell HDMI over coax extender:
http://sewelldirect.com/HDMI-over-Coax-Extender-.asp

I chose this for two reasons: first, it was rated to 328 feet instead of the 200 ft for network cable solutions. I estimate the distance we have to go at right about 200 ft and didn't want to push it. I think we have a Legacy building, built in 2002/3, with the a/v cabinet in the library at the opposite end of the building; if anyone has a better estimate let me know. Second, although it's more expensive there is no need to buy and install new cable, and the existing cable can still be used for satellite broadcasts.

I also purchased an HDMI to composite adapter from Radio Shack for the webcast until such time as we move to an HD webcast. One nice thing about the coax converter is each box is also a splitter/amplifier. So the receiver in the a/v cabinet has an HDMI output that feeds the webcast and a coax output that feeds the line to the cultural hall; there would be another receiver at the projector.

In testing we had mixed success. Most of the problems appear to stem from the connections. We initially tested with just a 15 ft cable in the same room and had an intermittent image. Tried a new BNC adapter and it worked fine. Then we sent the signal to the cultural hall and it was fine. Then we sent it to the chapel and got no signal. Thought it was just the distance, but after fiddling with the cables and connections got an intermittent image. We were able to get a steady image when we connected the receiver box straight to the installed coax.

If anyone has suggestions for getting better connections please let me know. I'm going to try some new BNC adapters, and will also put new connectors on the coax; the current ones seem pretty crudely installed. I know BNC connections are the norm in professional equipment, but it seems their main advantage comes when you have to re-connect cables periodically; I wish this product had regular f-connectors, as much as I hate them. But maybe someone can enlighten me on the advantages of BNC.

Since we were only sending a 720p image, the product is actually rated for 200 meters, so I hope distance or cable quality isn't the issue, but it clearly seems more sensitive to connection issues at longer distances.

We have two cables -- one for the composite signal and one for the modulated signal. They both appear to be home runs, but there is a third cable in the conduit at the a/v rack for the camera input in the overflow. I don't think either of the composite signals existed when they built the building, so not sure how they pulled the cable and put a split in the middle. Does anyone know where the conduit is in those buildings? In the a/v cabinet it goes down, as if it's in the foundation.

I'll keep you posted but any suggestions are welcome!

craiggsmith wrote:We initially tested with just a 15 ft cable in the same room and had an intermittent image. Tried a new BNC adapter and it worked fine.

Unless you can definitively trace that to a specific item, I'd worry that the system is overly sensitive. Intermittents are ugly as you can easily come to a wrong conclusion. Perhaps changing that adapter appeared to fix it, but the real problem is a poor connection internal to the box.

craiggsmith wrote:Then we sent it to the chapel and got no signal. Thought it was just the distance, but after fiddling with the cables and connections got an intermittent image. We were able to get a steady image when we connected the receiver box straight to the installed coax.

What was in between? Was this the composite line or the modulated line you were using?

craiggsmith wrote:We have two cables -- one for the composite signal and one for the modulated signal. They both appear to be home runs, but there is a third cable in the conduit at the a/v rack for the camera input in the overflow. I don't think either of the composite signals existed when they built the building, so not sure how they pulled the cable and put a split in the middle. Does anyone know where the conduit is in those buildings? In the a/v cabinet it goes down, as if it's in the foundation.

Most likely the cable makes takes a tour though another electrical box somewhere and that's where the camera connection takes off in a different direction. It might even be behind the camera connection in the overflow.

russellhltn wrote:Unless you can definitively trace that to a specific item, I'd worry that the system is overly sensitive. Intermittents are ugly as you can easily come to a wrong conclusion. Perhaps changing that adapter appeared to fix it, but the real problem is a poor connection internal to the box.

Agreed, I thought that at first, but it seemed to cut in and out when we wiggled the cables and connections. But I won't rule that out, will try the other things first. If I didn't have to worry about a warranty I'd take it apart and check, and maybe change it to an F connector. But the company is in Orem so I would have them look at it first.

russellhltn wrote:What was in between? Was this the composite line or the modulated line you were using?

Nothing in between per se, but there is a BNC adapter connected to a short cable connected to the installed cable via a coupler on each end.

I tried both cables. I'll look for a junction box in between.

It might not hurt to ping the manufacturer on their thoughts. Finicky is bad news. It can go bad on you when it feels like it.

russellhltn wrote:Most likely the cable makes takes a tour though another electrical box somewhere and that's where the camera connection takes off in a different direction. It might even be behind the camera connection in the overflow.

Cha-ching. 3 cables come into the box for the camera port, two continue on out (with a bunch of excess cable crammed into the box). The surprising thing is the opening is on the top; the modulated cables go down. But since this was probably all added later it makes sense, but I didn't see any cable in the mezzanine except the one they added recently for the cultural hall.

russellhltn wrote:It might not hurt to ping the manufacturer on their thoughts. Finicky is bad news. It can go bad on you when it feels like it.

I talked to them; they said they haven't heard any issues like this for that product and didn't have any suggestions.

Since I haven't gotten this to work, I tried using the HDMI to composite converter to just send a regular signal. Works fine when I run it straight off the PC, but not with the splitter in between. It seems to sense that it's there, as it automatically changes my computer to 1024x768, but no output. Darned if I do, darned if I don't.

craiggsmith wrote:I talked to them; they said they haven't heard any issues like this for that product and didn't have any suggestions.

Once you've exhausted your testing, you might want to ask for a exchange.

Finally have an update -- we got everything working fine. Did a lot of testing, including with a full 1080p image and longer leads. Not really sure why it works now; the only thing we did was put BNC connectors directly on the cable instead of using the adapters, but it was working fine before that. I was going to switch to a cat5 solution, but I had someone look at the building and he thought it would be pretty difficult to pull new cable through. So I'm pretty excited about this; we'll try it live next Sunday.

I think this is the most practical solution for the majority of existing buildings. I can provide a detailed list of parts if desired. Once the new webcast solution is up I think we'll be able to webcast it as well if needed. We could get an HDMI to VGA converter coupled with a VGA to composite converter now, but I've not had good results with that due to differing aspect ratios.