13V, 18V, 22KHz, and all that

[TheGear]

Could somebody point me to a discussion of how 13/18V and 22KHz are used to select transponders, and how to know what transponder is used for what channel? Also, I just moved into a house that has DirecTV with 4 LNBs. Is each of those LNBs specific to a particular combination of 13/18 and 22KHz/0KHz, or are they interchangeable? (To state it another way: Everything goes through a 4x8 multiswitch in the attic; can I swap the 4 LNB cables around, or must they stay at the ports they're connected to now?)

Thanks
gear

 

[Texanmutt]

13 volts selects the odd transponders and 18 volts the even. 22khz tone selects the other satellite on a dual sat LNB (i.e. 110-119).

Check out this link for more info-

http://ekb.dbstalk.com/217

 

[rkrenicki]

13/18v is used to select polarity on an LNB.. 13v is for vertical or right hand circular, and 18 for horizontal or left hand circular

a 22khz tone is used to select which LNB is currently active. On DirecTV, the 101 position is 22khz off, and 110/119 is 22khz on.

Now, DirecTV shouldnt have a 4 LNB dish.. there is a 1, 2, 3, and 5 lnb (which looks like 3) Do you mean that its a 3 LNB dish (three white caps facing the dish), and 4 outputs? If this is the case, then it does not really matter which wire is where, as long as all 4 are connected, but honestly, why mess with something that is already working?

 

[TheGear]

> why mess with something that is already working?

Well, that's the problem. We were in the eye of Wilma, and even before that we were having problems with a lot of channels simply dropping out for a second or two, every 5 or 8 seconds. Oddly, it doesn't correlate with weather as far as I can tell.

For less than the cost of two DirecTV service calls, I bought a Channel Master 1007IFD signal meter, and I'm trying to learn to use it. What I discovered is that the signal is noticeably better with 22KHz. Unfortunately, on DirecTV, that pretty neatly maps to the Spanish-language stations, which I can't use. But it raised the question in my mind about whether, perhaps, certain LNBs are aimed better or working better, and whether it might suffice to just swap cables around to the LNBs that perform better.

You're right--3 LNBs, 4 cables.

 

[rkrenicki]

It sounds more like the dish needs to be peaked.. you can try moving them around, but its not really going to make much of a difference.