Do I really need an attenuator?

Contributor

Do I really need an attenuator?

Tech said I'm 100 ft. from the VRAD and that I should use an attenuator. I wasn't really having any pixelation or intermittment connectivity issues so I let him add it to my modem. Not really noticing any difference afterwards, either. So I guess the question is do I really need to have it if I wasn't having issues? I'm from the school of thought that you WANT to be close to the box, not add a loop of "virtual" distance.

Message 1 of 11 (628 Views)
ACE - Expert

Re: Do I really need an attenuator?

Probably was no need to do that if you were having no problems, I'm 400' from my VRAD and have no problems too. Smiley Wink

 

Chris


Please NO SD stretch-o-vision or 480 SD HD Channels
Need Help? 1-800-288-2020, After he gets acct info, press # a bunch of times, get a menu from Mr. Voice recognition
Your Results May Vary, In My Humble Opinion
I Call It Like I See It, Simply a U-verse user, nothing more

*The views and opinions expressed on this forum are purely my own. Any product claim, statistic, quote, or other representation about a product or service should be verified with the manufacturer, provider, or party.
Message 2 of 11 (625 Views)
Employee

Re: Do I really need an attenuator?

Which RG do you have, the 3801 is designed to perform at longer loop length and have potential issues under 1000 feet, especially under 400 feet.
Solution to replace with 3800 improving test results or add attenuator (adds 1000') or install a box of wiring adding distance.
If 3800 and are indeed that close tech erred to side of caution (200 becomes 1200) but still within parameter of RG operating range.

From wiki
An attenuator is an electronic device that reduces the power of a signal without appreciably distorting its waveform.

An attenuator is effectively the opposite of an amplifier, though the two work by different methods. While an amplifier provides gain, an attenuator provides loss, or gain less than 1.

Attenuators are usually passive devices made from simple voltage divider networks. Switching between different resistances forms adjustable stepped attenuators and continuously adjustable ones using potentiometers. For higher frequencies precisely matched low VSWR resistance networks are used.

Fixed attenuators in circuits are used to lower voltage, dissipate power, and to improve impedance matching. In measuring signals, attenuator pads or adapters are used to lower the amplitude of the signal a known amount to enable measurements, or to protect the measuring device from signal levels that might damage it. Attenuators are also used to 'match' impedance by lowering apparent SWR.
Employee Contributor*
*I am an AT&T employee and the postings on this site are my own and don't necessarily represent AT&T's position, strategies or opinions.
Message 3 of 11 (623 Views)
ACE - Expert

Re: Do I really need an attenuator?

Yup, I have my old 3800 from my original install 5 years ago and it's still works just fine for me at 400'. Smiley Very Happy

 

Chris


Please NO SD stretch-o-vision or 480 SD HD Channels
Need Help? 1-800-288-2020, After he gets acct info, press # a bunch of times, get a menu from Mr. Voice recognition
Your Results May Vary, In My Humble Opinion
I Call It Like I See It, Simply a U-verse user, nothing more

*The views and opinions expressed on this forum are purely my own. Any product claim, statistic, quote, or other representation about a product or service should be verified with the manufacturer, provider, or party.
Message 4 of 11 (617 Views)
Anonymous

Re: Do I really need an attenuator?

I have never seen an attenuator actually do anything. If a 3801 is too close, you drop the profile to get sync, and it works fine. I think they are useless.

Message 5 of 11 (553 Views)
Employee

Re: Do I really need an attenuator?

The only effect of an attenuator is to reduce the signal strength.

 

The way most telco equipment is designed to operate is to transmit at full power, and reduce the signal at the receiver as necessary. If the signal is too strong, it tends to distort or reduce the sensitivity of the receiver over time. The attenuator brings the level down below the max acceptable strength.

 

The "sweet spot" for U-verse seems to be between ~1800 - 2400 feet.

 

Employee Contributor*
*I am an AT&T employee and the postings on this site are my own and don't necessarily represent AT&T's position, strategies or opinions.
Message 6 of 11 (515 Views)
ACE - Expert

Re: Do I really need an attenuator?

drumboy35 - Re: If a 3801 is too close, you drop the profile to get sync, and it works fine.

Are you saying that the customer could get 32/5 profile 4/0 HD and you reduce it to make it work??

I hope I am misinterpreting that.
*The views and opinions expressed on this forum are purely my own. Any product claim, statistic, quote, or other representation about a product or service should be verified with the manufacturer, provider, or party.
Message 7 of 11 (496 Views)
Anonymous

Re: Do I really need an attenuator?


aviewer wrote:
drumboy35 - Re: If a 3801 is too close, you drop the profile to get sync, and it works fine.

Are you saying that the customer could get 32/5 profile 4/0 HD and you reduce it to make it work??

I hope I am misinterpreting that.

Sorry, I didn't really explain it that well. For the initial bootup of an RG sometimes the 3801 won't sync up with the system on short loops (profile of 32/5). So you drop the profile temporarily to 25/2 allowing the RG to sync and register with the system. Once it is registered then it can be returned to 32/5 and will work fine.

Message 8 of 11 (476 Views)
Highlighted
ACE - Expert

Re: Do I really need an attenuator?

drumboy35 - Thank you for the clarification. Now the story has a happy ending.
*The views and opinions expressed on this forum are purely my own. Any product claim, statistic, quote, or other representation about a product or service should be verified with the manufacturer, provider, or party.
Message 9 of 11 (457 Views)
Employee

Re: Do I really need an attenuator?

[ Edited ]

drumboy35 wrote:

I have never seen an attenuator actually do anything. If a 3801 is too close, you drop the profile to get sync, and it works fine. I think they are useless.I am an AT&T employee and the postings on this site are my own and don’t necessarily represent AT&T’s positions, strategies or opinions.


The attenuators we use on short loops work well on those under 700' and are actually specifically called out for the purpose.   The work great when used because they help drop the error counts from the signal being too strong.  As for a sweet spot, the attenuator seems to add about 1000' to the system estimated loop length, so it would put those short loops over 1000' where the signal seems to be well balanced.  I haven't seen it as much of a problem on the 3800 but they do seem to help those modems as well.  So to the original question, yes they tend to help on short loops and since yours is under 400' it's probably a good idea if they put one on the modem.

 

 

 


 I am an AT&T employee and the postings on this site are my own and don’t necessarily represent AT&T’s positions, strategies or opinions.

Employee Contributor*
*I am an AT&T employee and the postings on this site are my own and don't necessarily represent AT&T's position, strategies or opinions.
Message 10 of 11 (437 Views)
Guru

Re: Do I really need an attenuator?

I'm very close to the VRAD myself and my RG accumulates corrected errors. Should I call someone out to install an attenuator on my line?
Message 11 of 11 (428 Views)
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