Wireless S/PDIF - Page 1
Forum section: electronics / rf-microwave

author: elektrinis
author_rank: Regular Contributor
timestamp: March 07, 2017, 09:57:22 am
content: Hello,So I have a home cinema setup with projector and media PC. I can not run any cables to the projector in this apartment, so I have installed it near light and connected supply from there. I can not run HDMI from it, so I threw a small android TV box on top of projector. Now I need to transfer 5.1 sound to my audio amp wirelessly. Don't ask how or why, but I have exhausted all other options, and now it is either wireless HDMI, or wireless S/PDIF. Tried the HDMI thing and it was horrendous: either you get terrible video quality with cheapo setup, or you have to invest 500 of money in to 50GHz setup. I have also tried software approaches with BT and WiFi, but latency is just too high.Anyway, requirements for S/PDIF:Signal: digital, one way only, no flow control.Rate: 6mbpsDistance: 5 meters.Now I have googled back and forth and was only able to come up with this:http://www.latentlaboratories.com/blog/2014/10/11/12-wireless-lossless-digital-audioWell, it almost worked. The signal was too much distorted and could not be decoded by the receiver.Also one more tiny issue: it completely killed my mikrotik (and likely neighbors) WiFi AP, channel switching did not help.So I was looking at all kinds of cheap solutions.. like other NTSC TX-RX kits, general purpose serial RF modules etc... Just could not find anything that works.I don't really want any extra boxes in my home, would prefer a small module that I could integrate inside my TV box and audio setup.Any suggestions?

author: cncjerry
author_rank: Unknown
timestamp: March 17, 2017, 05:04:28 pm
content: I stream wireless HD video all the time using my laptops, etc. I'll bet a raspberry PI would work as a receiver. This assume of course that you have a library of video on another computer or you can use eyeTV maybe or other streaming HD servers. Just a thought. You can't hide the wire under a rug or something? I had this same problem and made an SPID/F converter box with a couple of stacked inverter ICs and a optical driver from an old CD player. It took the optical and converted it to RCA jack. And that does bring up an idea, if you took the SPID/F output and boosted it again with some IC buffers or line drivers, inverters like 7400 series, maybe a transistor output stage and used a little laser diode from a DVD burner (you can get them online) and pointed it at an SPID/F receiver, I'll be you can get a signal across the room. I'm not sure if the SPDI/F receivers only respond to red light or not, I don't remember there being a filter on the receiver, but if there is, maybe you can cut it out some how. That way the I/R laser diode would activate the receiver. A good, bright red LED might do the same thing.I was playing around with a headset you could wear on an airplane that broadcast I/R two-way radio so you could have a conversation with someone sitting in the back of the plane if you couldn't sit together. Then I thought, heck that's about the only time I get peace and quiet is on an airplane and my wife and kids are in the back. Hey, is it my fault they don't get automatic first class upgrades? Why should I sit in the back? I've earned those miles by flying every freaking weak for the past five years. Ha!I guess I don't understand your layout. If you are getting HDMI to your projector, why can't you just run the HDMI Audio? Or are you saying the projector and PC are in one location and the stereo in another and you want to run the projected audio to the stereo? Whatever the setup, if you are handy with electronics and have a stack of old equipment around, you can throw together that what I described above in an afternoon.

author: elektrinis
author_rank: Regular Contributor
timestamp: March 17, 2017, 06:47:43 pm
content: The setup is simple really. There is a powerful 5.1 audio system, it accepts S/PDIF only, optical and RCA. The amp is installed in a corner of the room.Also there's a PC in the same corner. It contains all of media, has both spdif and HDMI out, is accessable over network.Here's the difficult part: there is a projector hanging on the ceiling, in the middle of room, and it only takes HDMI and I can't run cables.I have two options.1. Run media player (Kodi) on PC and use wireless HDMI to projector. Tried and failed, so not really an option.2. Run an Android TV box near projector, run media player there. Basically on top of it, hanging on the ceiling. But then I have to route oudio wirelessly to PC or amp. Bluetooth and WiFi audio options did not work.So how do I transmit S/PDIF wirelessly?