What is the "switch"?

[Phils]

Hope no one is offended by such a simple question.... "glossary" didn't help.

What is the "switch" that "check switch" checks? Must be in the LNB assembly since I don't see it anywhere else? Is it an electronic switch or mechanical? How does it work? And why does it sometimes need to be reset by the "check switch" operation?

I've seen different switch numbers mentioned here -- and those sound like they are physically mounted in another location from the dish?

Maybe someone can give me a link to "switches for dummies"?

Phil

 

[garys]

Some switches are seperate while others are built into the lnb's. What does you check switch setup state?

 

[boba]

Over the years DISH has used many switches to allow access to different satelite combinations. The first was for 119 & 110 it was the SWAJ which is no longer sold or supported. Some of the switches are SW21/SW42/ Sw44/ SW64/ Legacy Twin/ Legacy Quad/DP21/DP34 DP Twin/ DP Quad & DPP44. Did I miss any? I probably did but that is why a switch check is done so the receiver knows which switch it is required to use so you can see your satellite signals.

 

[bhelms]

You can look at one of your System Setup information screens (I forget the exact screen name) to see what equipment is connected in your system. If you see a DP34 (DishPro34) or DPP44 (DishProPlus44) etc. in your "Device" line, then you have an external switch (i.e., separate from the LNBs). A "DPP Twin" is an LNB with the switch built in, etc.

Here is a link to some valuable Dish equipment information:

http://ekb.dbstalk.com/swconfig.htm

 

[Phils]

Thanks for the link bhelms.

I can't say I fully understand it yet, but I'm closer. Maybe after I digest the reading it'll come into better focus.

Phil

 

[Pepper]

Simplistic answer...

Each satellite your dish(es) point at has a separate LNBF which receives odd and even transponders from that satellite only. The switch is the part in between all the LNBF(s) and the receiver(s). The receiver tells the switch which satellite and polarity it wants, and the switch "switches" the output to the desired input.

In some cases such as the various Twin and Quad LNBFs, the switch is an integrated part of the assembly.

 

[jerryez]

Run the switch check and the results will show you which lnb and switch that you have. It will print out on your tv screen when the switch check is complete.

 

[Phils]

I've seen the switch info, I'm still a little hazy on what "check switch" actually does and why it occasionally needs to be run in order to reset it. Is it actually checking that the switch is working properly or just that it's there?

From what I gather from these posts, the switch is changing when different channels are selected?

Phil

 

[Pepper]

the "check switch" test determines what kind of switch is there, what type of LNBF equipment is connected to the inputs, and what satellites and polarities each of them can receive.

The test should only have to be run again if there is some sort of problem or you point one of your dishes at a different satellite.

 

[Phils]

Thanks Pepper. You made it sound easy.

I haven't needed to run 'check switch' except at install but I've seen enough posts here about doing it, maybe sometimes to determine if the LNB is bad.

Just didn't know what the heck it was doing during the test. Hopin' to not have to do any troubleshooting but I like to know my options.

Phil

 

[Smith P.]

"test determines" and store all the info into NVRAM, keep it and use it all time up to next check [sorry Pepper, can't resist to make final point in your speech ]

 

[Pepper]

no problem Smith, just trying to keep it simple. I didn't mention the difference between the legacy and dishpro checks either on purpose.

 

[rglore]

Some more basic info...

LNB - The head on the dish that receives the microwave signal from the satellite and converts it to a lower frequency that the RG6 coax can handle.

Switch - The first Dish Network dishes had a single electronic switch in the dish's LNB that the receiver could control to make it switch between the channels that were sent with clockwise polarity frequencies or the ones with counter-clockwise polarity. LNBs show in check switch as single or dual or quad depending on how many connectors are on the LNB for connecting to one or more receivers or external switches.

Later, Dish added satellites in different orbital locations and designed a dish with two LNBs, one for satellites in the original 119 location and one for the new 110 degree orbital location. To connect the receiver to two LNBs required an additional switch between the receiver and the LNBs to select which LNB was required to feed the frequencies for the currently selected channel to the receiver. Dish has satellites at six orbital locations and dishes with one, two and three LNBs. Dish later created DishPro "Twin" double LNBs with the external switch built into the unit in dual and quad feed models. (DishPro single/dual LNBs have no switch since both polarity's frequencies are sent together) Lastly, Dish created DishProPlus twin and triple LNBs and switches that can feed dual tuner receivers with one coax.

External LNB switches have a numbering system where the letters denote the signaling technology (SW-legacy, DP and DPP) followed by two numbers. The first number denotes the number of connections to LNBs and the second is the number of connections to receivers/tuners. The switch model will also show on the check switch screen. Legacy switches require two connections to each LNB.

 

[BobaBird]

Dish later created DishPro dual LNBs with the external switch built into the unit

A DP Dual is one LNB for one satellite, usually run through a switch.
What you're describing is a DP Twin - 2 DP LNBs and a switch in one wide housing.

 

[rglore]

Charles, thanks, i edited my post, I try to not add to the confusion.

 

[Phils]

Not necessary to respond unless I'm wrong:

When I switch channels on my 622, the receiver tells the "switch" which channel I want and it then selects the proper satellite/transponder to meet my demand.

I always assumed (and you know what that means) that like an antenna, ALL the channels were coming in through the coax to the receiver. Now, I see that only the channel I've selected is traversing the coax from dish to receiver. And that is compliments of the "switch".

If the above paragraphs are correct then thank you all, as you have increased my knowledge base. Besides that, maybe I now understand it.

Phil

 

[RandallA]

This document summarizes what Pepper, Smith P and Bob have said and it adds a little more (good reading to understand how Dish Pro works):

http://www.solidsignal.tv/dishnetwo...ments/Introduction_to_DISH_Pro_Technology.pdf

 

[Smith P.]

If you wand to know more about different configs - check all that PDFs at the page.

 

[rglore]

Phil,

The receiver doesn't tell the switch what channel you want. Each LNB receives two groups of up to 36 different frequencies/transponders and two polarities. Each frequency can carry from several to twenty or so channels (half each polarity) depending on the channel's required TV resolution. The receiver only tells the switch what LNB to use and which frequency group or groups to send over the coax. DishPro LNBs can send both groups together (band stacking) and DishProPlus can send one group from two different LNBs together.

 

[Smith P.]

Not 36, but up to 32 tpns.