Jump to content


Welcome to DBSTalk


Sign In 

Create Account
Welcome to DBSTalk, like most online communities you must register to view or post in our community, but don't worry this is a simple free process that requires minimal information for you to signup. Be a part of DBSTalk by signing in or creating an account.
  • Start new topics and reply to others
  • Subscribe to topics and forums to get email updates
  • Get your own profile page and make new friends
  • Send personal messages to other members.
 
Guest Message by DevFuse

Photo
- - - - -

Genie "The Good Stuff" Discussion


  • Please log in to reply
138 replies to this topic

#121 OFFLINE   Rich

Rich

    Hall Of Fame

  • DBSTalk Club
  • 19,403 posts
  • LocationPiscataway, NJ
Joined: Feb 22, 2007

Posted 29 November 2012 - 03:58 PM

I'm searching for specs but from what I've been able to gather (without chopping up my S/PDIF cables) is that they have a 7 conductor stranded center core. Other than that they appear to be the same as your "standard" RG6 as far as the braided outter core.

They are both listed as "75 ohm coax".

UPDATE: What's the difference? Apparently the type of coax used for connecting satellite and antenna feeds are "a completely different kettle of fish". Does that explain it enough? :lol:

http://www.dummies.c...nd-optical.html


I keep trying to put this stuff in an electrical context so I can understand it and I think that's how this got so confused.

Rich

...Ads Help To Support This SIte...

#122 OFFLINE   harperhometheater

harperhometheater

    Legend

  • Registered
  • 181 posts
Joined: Aug 30, 2012

Posted 29 November 2012 - 04:01 PM

It's not necessarily the cable that matters, it's the impedance. "Coaxial digital" audio signals are designed to work best on 75 ohm coaxial cables, the exact same ones used for composite video and each channel of a component YUV/YCbCr/YPbPr cable. The type of connector (RCA, BNC, F-type) just depends on what the manufacturer decides to use and doesn't matter a lick as long as they are also 75 ohm impedance. If they aren't then the signal "should" still work (like if you use the cheap throw in the box cables) but you will have signal issues like reflections, impedance mismatches, jitter, ghosting, etc. If those issues become too great for the decoding end to overcome then the signal will fail.

Edited by harperhometheater, 29 November 2012 - 05:36 PM.

HarperVision, LLC
ISF Calibrations, Installations,
Repairs & Consultations

#123 OFFLINE   Rich

Rich

    Hall Of Fame

  • DBSTalk Club
  • 19,403 posts
  • LocationPiscataway, NJ
Joined: Feb 22, 2007

Posted 29 November 2012 - 04:06 PM

I find this somewhat odd. I have never put RCA connectors on rg6 sat coax and tried it for digital coax connections, but I would think it should work, for that works fine for regular composite video from what I have seen, and composite video cables work fine for digital coax cables, which I have tried.


I couldn't do it. I put soldered jumpers on the other end and it just wouldn't work. It rang out correctly for continuity, for whatever that's worth. That was quite a while ago and I think it was an upscaling DVD player that only had a digital audio cable output on it.

So, after going thru all that, I could have just used a composite wire? Geeze, that doesn't seem fair... :lol:

Rich

#124 OFFLINE   RunnerFL

RunnerFL

    Hall Of Fame

  • DBSTalk Club
  • 15,506 posts
Joined: Jan 04, 2006

Posted 29 November 2012 - 04:07 PM

It's not the cable that matters it's the impedance. "Coaxial" digital audio signals are designed to work best on 75 ohm coaxial cables, the exact same ones used for composite video. The type of connector (RCA, BNC, F-type) don't matter a lick as long as they are also 75 ohm impedance. If they aren't then the signal should still work ( like if you use cheap throw in the box cables) but you will just have signal issues like reflections, impedance mismatches, jitter, ghosting, etc. If those issues become too great for the decoding end to overcome then the signal will fail.


If S/PDIF is a 75ohm coax what is the standard RG6 we use for SAT signals?
THIS SPACE FOR RENT

#125 OFFLINE   RunnerFL

RunnerFL

    Hall Of Fame

  • DBSTalk Club
  • 15,506 posts
Joined: Jan 04, 2006

Posted 29 November 2012 - 04:08 PM

I couldn't do it. I put soldered jumpers on the other end and it just wouldn't work. It rang out correctly for continuity, for whatever that's worth. That was quite a while ago and I think it was an upscaling DVD player that only had a digital audio cable output on it.

So, after going thru all that, I could have just used a composite wire? Geeze, that doesn't seem fair... :lol:

Rich


You could have used composite, yes, but there's no guarantee you would have had great audio. :lol:
THIS SPACE FOR RENT

#126 OFFLINE   harperhometheater

harperhometheater

    Legend

  • Registered
  • 181 posts
Joined: Aug 30, 2012

Posted 29 November 2012 - 04:15 PM

If S/PDIF is a 75ohm coax what is the standard RG6 we use for SAT signals?


75 ohm as well. RG6 is a cable designed for higher frequencies than low level audio and video interconnects, but should still work. That's why they have quad shield RG-6 because at higher frequencies the cable starts acting like an antenna and starts radiating the signal out of the dielectric and shielding, I.e. skin effect. This is exactly why there is indeed some differences in cheap vs well designed and constructed cables like JPS Labs, Monster, etc. but of course they go overboard with their claims and prices and if you look hard enough will find affordable well made and designed cables elsewhere (monoprice, blue jeans, etc.)

Edited by harperhometheater, 29 November 2012 - 04:30 PM.

HarperVision, LLC
ISF Calibrations, Installations,
Repairs & Consultations

#127 OFFLINE   harperhometheater

harperhometheater

    Legend

  • Registered
  • 181 posts
Joined: Aug 30, 2012

Posted 29 November 2012 - 04:18 PM

You could have used composite, yes, but there's no guarantee you would have had great audio. :lol:


Yes it would have been, IF the cable was designed correctly at 75 ohms impedance! Composite video cables and digital audio cables are EXACTLY the same.
HarperVision, LLC
ISF Calibrations, Installations,
Repairs & Consultations

#128 OFFLINE   Mike Bertelson

Mike Bertelson

    6EQUJ5 WOW!

  • Moderators
  • 13,791 posts
Joined: Jan 24, 2007

Posted 29 November 2012 - 04:22 PM

Thanks, but I was asking about the cable itself: Is the word "digital" added to make it sound more modern (sorta like a "digital TV stand") or are they in fact different from any other coax in the cabling?

I took the three wire cable with the yellow/white/red connectors (standard composite video, R/L audio cable) and used it to connect digital coax to my A/V system. It's nothing special and it works great. The yellow composite video is a 75Ω coax cable with RCA connectors.

Mike

Edited by Mike Bertelson, 29 November 2012 - 04:34 PM.

µß
If you don't want to do sub-models at least do the new equipment...I'm just sayin'
Since it costs 2.4¢ to produce a penny, my 2¢ worth is really 4.8¢ worth.  That 4.8¢ is my own and not the 4.8¢ of DIRECTV, Dish, or anyone else for that matter.


#129 OFFLINE   Laxguy

Laxguy

    Hall Of Flame

  • DBSTalk Club
  • 10,766 posts
  • LocationWinters, California
Joined: Dec 02, 2010

Posted 29 November 2012 - 04:53 PM

That kinda tops it up! So the word "digital" is market speak, and there's no difference between a well made "analog coax" and a so called "digital coax."
Interesting discussion none-the-less.
"Laxguy" means a guy who loves lacrosse.

#130 OFFLINE   carl6

carl6

    Hall Of Fame

  • DBSTalk Club
  • 10,666 posts
  • LocationSeattle, WA
Joined: Nov 15, 2005

Posted 29 November 2012 - 05:36 PM

That kinda tops it up! So the word "digital" is market speak, and there's no difference between a well made "analog coax" and a so called "digital coax."
Interesting discussion none-the-less.


Exactly true. Just like there is no such thing as a "digital" tv antenna, or an "HD" tv antenna. All market speak.

A rose by any other name is still a rose.

#131 OFFLINE   harperhometheater

harperhometheater

    Legend

  • Registered
  • 181 posts
Joined: Aug 30, 2012

Posted 29 November 2012 - 05:38 PM

A rose by any other name is still a rose.


And so is a turd :D
HarperVision, LLC
ISF Calibrations, Installations,
Repairs & Consultations

#132 OFFLINE   jangell2

jangell2

    Godfather

  • Registered
  • 275 posts
Joined: Apr 06, 2004

Posted 30 November 2012 - 09:27 AM

Exactly true. Just like there is no such thing as a "digital" tv antenna, or an "HD" tv antenna. All market speak.

A rose by any other name is still a rose.

Ok, now you're gonna tell me those "HD" sunglasses that were being sold on TV aren't really high definition? :lol:
johnny
www.teamfurr.org

#133 OFFLINE   Laxguy

Laxguy

    Hall Of Flame

  • DBSTalk Club
  • 10,766 posts
  • LocationWinters, California
Joined: Dec 02, 2010

Posted 30 November 2012 - 10:05 AM

Ok, now you're gonna tell me those "HD" sunglasses that were being sold on TV aren't really high definition? :lol:


The ones that are digital are.....:D
"Laxguy" means a guy who loves lacrosse.

#134 OFFLINE   jangell2

jangell2

    Godfather

  • Registered
  • 275 posts
Joined: Apr 06, 2004

Posted 30 November 2012 - 01:16 PM

Got a question about the two 90 minute buffers. My HR20 constantly kept one buffer going, no matter it was in stand-by mode or not. It seems the HR34 does not. When I start it up in the morning, there is no buffer, is this the designed behavior?
johnny
www.teamfurr.org

#135 OFFLINE   RunnerFL

RunnerFL

    Hall Of Fame

  • DBSTalk Club
  • 15,506 posts
Joined: Jan 04, 2006

Posted 30 November 2012 - 01:18 PM

Got a question about the two 90 minute buffers. My HR20 constantly kept one buffer going, no matter it was in stand-by mode or not. It seems the HR34 does not. When I start it up in the morning, there is no buffer, is this the designed behavior?


Some may lead you to beleive it's designed behavior and the rest of us think it's a bug. Sometimes there is a buffer, sometimes there is not. If what we are seeing is designed behavior then there should never be a buffer at all.
THIS SPACE FOR RENT

#136 OFFLINE   jangell2

jangell2

    Godfather

  • Registered
  • 275 posts
Joined: Apr 06, 2004

Posted 30 November 2012 - 03:00 PM

Some may lead you to beleive it's designed behavior and the rest of us think it's a bug. Sometimes there is a buffer, sometimes there is not. If what we are seeing is designed behavior then there should never be a buffer at all.

What I would have liked to see was a user selectable period of time in which a buffer would not be kept. Let me choose between the hours of 11pm-7am to not carry a buffer. The idea being to cut down on the HD drive activity and increase it's lifespan and reliability.

When no buffer is being kept, do we know what the HD is doing, is it spinning down or constantly running?

I'm going to pay closer attention, but so far, I don't think I've ever seen a buffer in the morning.
johnny
www.teamfurr.org

#137 OFFLINE   jangell2

jangell2

    Godfather

  • Registered
  • 275 posts
Joined: Apr 06, 2004

Posted 30 November 2012 - 03:08 PM

An update to my using the DTV remote for the HR20 and the Harmony for the HR34. Whenever it would use the Harmony to go from the HR20 to HR34, everything was fine, the HR34 powered on...and then it would shut off.

I was really perplexed about this until I realized the Harmony was attempting to shut of the HR20 (it couldn't, its on RF) but was succeeding in shutting off the HR34 which was not a desirable behavior when trying to watch the HR34.

So I updated to the remote to leave the HR20 on and now it get the results I want.

It was a Homer Simpson "Doh!" moment. :)
johnny
www.teamfurr.org

#138 OFFLINE   dennisj00

dennisj00

    Hall Of Fame

  • DBSTalk Club
  • 7,900 posts
  • LocationLake Norman, NC
Joined: Sep 27, 2007

Posted 30 November 2012 - 03:17 PM

Hard drive activity has very litte effect on the life of the hard drive. Power cycles, extreme temperatures or mechanical shock are far bigger factors in hard drive life.

Spending to stimulate the economy as fast as the credit cards will allow!

My Setup / Weather at Lake Norman!/ Boathouse BEES
DLB, MRV, nomad, HDGUI are HERE! . . . We're DONE!


#139 OFFLINE   RunnerFL

RunnerFL

    Hall Of Fame

  • DBSTalk Club
  • 15,506 posts
Joined: Jan 04, 2006

Posted 30 November 2012 - 04:42 PM

What I would have liked to see was a user selectable period of time in which a buffer would not be kept. Let me choose between the hours of 11pm-7am to not carry a buffer. The idea being to cut down on the HD drive activity and increase it's lifespan and reliability.

When no buffer is being kept, do we know what the HD is doing, is it spinning down or constantly running?

I'm going to pay closer attention, but so far, I don't think I've ever seen a buffer in the morning.


Spinning a drive up and down is more wear and tear on the drive than just letting it spin 24/7.
THIS SPACE FOR RENT




spam firewall