Question Regarding PCM and Analog Audio (1 Viewer)

[Ralph Summa]

I have my Hughes E86 connected to my Yamaha A/V receiver via optical cable. The Hughes has an ATSC tuner, NTSC tuner and DirecTV tuner.

In what format does the NTSC analog audio get sent to the Yamaha? Should it be a PCM signal?

I ask because I recently lost the audio for all my NTSC channels. ATSC audio and DirecTV audio work fine. whentuned to an ATSC channel the Dolby Digital (2.0) light is on. when tuned to DirecTV stations, the PCM light is on. When tuned to NTSC analog channels PCM light is on, the video is fine, but there is no sound.

I am at my wits end! I have tried everything I can think of to change this with no luck.

Ralph

 

[Marc Rochkind]

Well, PCM is a digital format, for starters.

When you say you "recently lost the audio," do you mean that you used to get NTSC analog audio, and now you don't? What changed recently?

I don't know this equipment specifically, but I would think that for NTSC there must be an analog phono cable going from the set-top-box to the receiver, and that the receiver must have its options set so that it is playing analog from that channel. Possibly you have the analog cable connected to a digital output (the connector is identical) or digital input.

 

[Ralph Summa]

Marc,

The optical connection is the only one between the two units. I did have analog audio before Sunday. The two components have been working flawlessly for over five months. I don't know what happened. I did not move cables components etc. There are no real audio settings on the STB except Dolby Digital on/off. I switched that for the heck of it but no dice. I am going to attempt to call Yamaha customer support tonight. They said they would walk me through some tests. I have tried everything.

The only thing I can't verify is if the PCM light was on when the Hughes was tuned to analog TV, previous to Sunday.

 

[Vince Maskeeper]

Ralph,
I would call Yamaha about it- as you didn't change anything, yet the audio stopped working.
One thing to note, you should be careful with your terminology when you contact customer support. Realize that the PCM connection is a digital connection- so if you were getting audio via only that cable- the box was somehow providing "DIGITAL AUDIO"- even if it came from an analog channel. I would assume the box has some sort of internal conversion for compatibility sake (good feature, I wish more companies were concerned about compatibility!)
But, above you said:
When it would be more accurate to say you had audio from the analog NTSC stations before Sunday... because again if the audio was actually "analog" in nature it couldn't be passed via the PCM connection! Since it was passed via the PCM connection- at some point it must ahve been converted to digital. This issue might serve as a confusion for technical support- as I found it confusing the first time I read your post.
So, when you talk with customer service, I would even consider leaving out the terms digital and analog- as it might only serve to confuse the situation. The bottom line is you had previously been able to get audio from all 3 bands (NTSC, DirectTV, ATSC) via the optical cable output on your box connected to your receiver- and now only 2 of the 3 are providing audio.
-Vince

 

[Ralph Summa]

Vince,

Point taken. I rewrote my post three times because I kept confusing myself. That is exactly the case. I had audio from NTSC stations last week, and today I do not.

A few months back I had a problem with the Hughes box losing NTSC video while NTSC audio continued to work. The entire motherboard of the Hughes had to be replaced. I hope I don't have to live without my HD box for five weeks again.

 

[Ralph Summa]

Well, I spoke with Yamaha tech support and we detemined that it is a STB issue. The tech had be set up an analog (composite) connection out of the STB to the Yamaha and try the audio. Same deal. No audio from NTSC and audio was fine from DirecTV and ATSC.

I called Hughes tech support next and they were completely baffled by the problem, much like they were when I had the NTSC video problem. They actually called up the old service issue and they thought that was bizarre too. Tried soft reboot, hard reboot, rescanning, reentering zipcode. No change. Again I am referred to an authorized service center. Another 5+ weeks with without the STB. The NTSC tuner in the first unit failed after 6 weeks the replacement motherboard failed after four months. It's still under warranty, but the inconvenience just sucks...

 

[Marc Rochkind]

Ralph...

Sounds like between you and Vince the problem has been identified. Too bad about losing the STB. I will remember that this was a Hughes brand STB!

 

[Ralph Summa]

Yeah it's a bummer to lose the box again, and when it works it has great features and performs really well. But with all the aggravation, I wish I could just get my money back and try something else.

I wonder if it's heat causing the problems. I have a two fans in my enclosed cabinet and one keeps my Yamaha very cool. The Hughes has always run hot. It was still warm at 6:30 this morning even after being off for over 8 hrs. It just seems strange that I haven't encountered anyone else who has had problems like the ones I had, and both problems I encountered had to do with NTSC channels. So, I wonder is the NTSC tuner defective from the manufacturer or is the NTSC tuner a sensitive part of the unit that can't take excessive heat?