sat kills signal

[ohmster]

I have an install that is giving me fits.
I have Direct and a roof top ant. Both signals are sent via seperate coax to distribution box. I now use a diplexer and send the signals to a remote location where the sat box is. Signals are now seperated with the LNB going to sat box. The ouput of box is modulated to channel 14 and combined with the ant signal, sent back to distribution box, amplified and sent to whole house.
Problem is, if I disconnect the incoming LNB signal to the first diplexer I get great signal. When the LNB is hooked back into diplexer it kills my signal!!!!
I have tried different diplexers ( am using high end channel master) I have tried different combiners, I think I have tried everything I can think of.
Any help would be appreciated, thanks.
note: When I say kills signal, there is some signal but very snowy.

 

[Joe Diamond]

I have an install that is giving me fits.
I have Direct and a roof top ant. Both signals are sent via seperate coax to distribution box. I now use a diplexer and send the signals to a remote location where the sat box is. Signals are now seperated with the LNB going to sat box. The ouput of box is modulated to channel 14 and combined with the ant signal, sent back to distribution box, amplified and sent to whole house.
Problem is, if I disconnect the incoming LNB signal to the first diplexer I get great signal. When the LNB is hooked back into diplexer it kills my signal!!!!
I have tried different diplexers ( am using high end channel master) I have tried different combiners, I think I have tried everything I can think of.
Any help would be appreciated, thanks.
note: When I say kills signal, there is some signal but very snowy.

This assumes you are using a HD receiver.........report back which Dish, LNB & receiver plz.

Try removing the BBC (filter at the back of the DTV receiver) AND moving it upstream to above the diplexer to give you the setup DISH / LNB...line...BBC...diplexer IN...line....diplexer OUT....line.....SAT IN receiver.

Know that those BBCs are not weather proof and this procedure is not "supported" but may work if I understand your problem.

Report back,

Joe

 

[downthedoor]

I used to work for a firm that did HD upgrades for D* and if I remember correctly you can not use a diplexer with the new HD because of interferance. Call D* and ask them to search for diplexer and see what they find.

 

[ohmster]

This assumes you are using a HD receiver.........report back which Dish, LNB & receiver plz.

Try removing the BBC (filter at the back of the DTV receiver) AND moving it upstream to above the diplexer to give you the setup DISH / LNB...line...BBC...diplexer IN...line....diplexer OUT....line.....SAT IN receiver.

Know that those BBCs are not weather proof and this procedure is not "supported" but may work if I understand your problem.

Report back,

Joe

Thanks for the reply. I am using a H21-200 receiver with the 5 LNB dish. Thanks.

 

[harshness]

DIRECTV recommends AGAINST diplexing.

If you are going to do it anyway, you need to have both diplexers inserted between the BBC and the receiver. There are numerous threads here that discuss how it is done as well as why it shouldn't be done.

 

[texasbrit]

The issue is that the signals from the new satellites DirecTV10 and DirecTV11 (which carry the HD channels) are in the same frequency band as OTA and so the older diplexing installations will not work. Who installed your dish/system, if it was an installer they should have known this would not work?
There are only a few solutions. The first is to run a separate cable for the antenna signals. The second is to relocate the BBCs as Joe and Harkness mention, the BBC has to be before the fisrt diplexer (the one that brings in the cable from the antenna). It's a work-around not supported by DirecTV, the BBCs are not designed to be remote from the receiver. Additionally the BBCs are as Joe posted not weatherproof so if you wanted to put a BBC outside you would have to build a special enclosure. And the third solution, assuming the H21 is your only receiver, is to replace the LNB at the dish with an SWM LNB. Your sat signals then come to the house over a single cable, and none of the SWM frequencies interfere with antenna signals so you can use diplexing the way you always did. A couple of caveats (mentioned by Harkness). Diplexing might not work because some diplexers don't pass the 2.3MHz control signal between the receivers and the SWM. And because of this and other potential issues, DirecTV does not officially support diplexing with SWMs, although there are many people (including me) who run diplexed systems with an SWM with no problems.