Need help with all these terminologies/definitions

[be236]

Hi,

Still relatively new to this FTA scene...

Anyways, can some define/describe these terminologies.

1. DiSeqC switch (looks like a regular F-connector cable splitter block, right?) (this allows for multiple LNBs to be connected, and is to control which LNB connection gets passed to the receiver , right?)

2. USALS (is this a protocol to allow moving of the dish with HH motors)? Why do I see DiSeqC mentioned in this same area? What does DiSeqC have to do with motor movement?

3. 22khz switch? There is a setting in my Fortec receiver for this.. What does this do?

[boroda1]

Originally Posted by be236

2. USALS (is this a protocol to allow moving of the dish with HH motors)? Why do I see DiSeqC mentioned in this same area? What does DiSeqC have to do with motor movement?

There are several DISEqC protocols. One of them, DiSEqC 1.2 is also about moving a dish with a motor from one "position" to another. USALS is an enhancement of this protocol, and sometimes is advretised as "DISEqC 1.3" on receiver carton boxes.
{EDIT} Here is a Wikipedia link for you: http://en.wikipedia.org/wiki/DiSEqC

[be236]

Ok, so that is why it's confusing... DiSeqC 1.2 is the protocol to move the HH motor, while a DiSeqC "switch" is that little square metal block that looks like a cable splitter that allows you to switch LNB ports when you have multiple LNB feeds into it, right?

[elgemcdlf]

Correct. DiSEqC switches come in 2 varieties that I know of. Either 2 or 4 port. Basically as I see it most everything that comes out of the receiver in the way of commands falls under the DiSEqC heading. Exception being 22khz. Anyway it is more like DiSEqC is a grouping, you have motors that accept DiSEqC commands, switches that accept DiSEqC commands. USALS in simplistic terms is a group of preprogrammed DiSEqC commands for a DiSEqC compliant motor. Perhaps protocol would be a good choice for describing DiSEqC.

This is not exactly how it is but will give you a simplistic idea of the structure. USALS actually calculates based on the entries you make into the receiver and so on.

[wejones]

I may be wrong (as usual), but the way I understand it, DISEQC commands are all digital commands modulated on a 22KHz carrier. The DISEQC-1.2 is a set of these commands used to control the motors. The motors have something like 50 preset positions stored in the motor, and the DiseqC commands just tell the motor to go to one of these preset positions. You can manually move the dish east or west when finding sats, then store the current position into one of the preset positions.
The way I understand it, USALS, is basically ONE additional diseqC command, which is basically a GOTO-X command, where the X is a number of degrees that the motor is to turn east or west from it's zero position. I think the resolution is about .1 degree. (1/16th rounded off to 1/10th). It is the receiver that does the USALS calculation. USALS is simpler for the beginner, since you don't have to search for the sats, you just tell the receiver what longitude you and the sat are at, and it does the rest. DISEQC commands require you to program each satellite, but has the advantage of having a little more control, allowing you to fine tune the sat positions.
If you have an oscilloscope, you can hook it up to your coax, and see the DISEQC commands being sent. Basically just a 22KHz signal that goes on and off to represent binary 1/0 conditions.

The part that I'm confused about is that there are 2 different types of DISEQC switches, and I don't know how they differ. One is called a mini tone burst or something like that, and the other is just plain DISEQC. The tone burst switches apparently use letters for the ports, like A,B, etc, while the regular DISEQC switches seem to use numbers, but I've found that either numbers or letters seem to work with both, so it doesn't seem to be a real difference.. I think my 4 port switch, which has given me nothing but trouble is a plain DISEQC, while my 2 port switch is the mini tone burst type, and it has been very reliable. I got both at Sadoun, but Sadoun doesn't seem to sell the 2 port switches anymore. Too bad, because the 4 port switches seem to have problems.

[be236]

So, there are basically 2-port (connects two LNBs) and 4-port DiSeqC switches... Does this mean the max number of LNBs a receiver can hook up to is 4?

Or can you "daisy" chain one DiSeqC switch to another (ie, cascading) so that you can get more than 4?

(yes, I know most people probably dont need more than 2 or 4 LNBs hooked up a to single receiver)..hhehe...

[rainman]

Originally Posted by be236

So, there are basically 2-port (connects two LNBs) and 4-port DiSeqC switches... Does this mean the max number of LNBs a receiver can hook up to is 4?

Or can you "daisy" chain one DiSeqC switch to another (ie, cascading) so that you can get more than 4?

(yes, I know most people probably dont need more than 2 or 4 LNBs hooked up a to single receiver)..hhehe...

yes you can daisy chain with splitters and disqec switches.

[wejones]

Originally Posted by be236

So, there are basically 2-port (connects two LNBs) and 4-port DiSeqC switches... Does this mean the max number of LNBs a receiver can hook up to is 4?

Or can you "daisy" chain one DiSeqC switch to another (ie, cascading) so that you can get more than 4?

(yes, I know most people probably dont need more than 2 or 4 LNBs hooked up a to single receiver)..hhehe...

Oh, I don't know how high the number of ports can get. I know the receivers can put out numbers greater than 4, although I've never seen greater than "B" on the mini tone burst things. I'd guess that you can find switches with more than 4, but I haven't really looked around.

When my Ultra used to go beserk when the memory overload, I used to find the DISEQC set on numbers like "87", which would take a long time to get back to "2" with the left arrow on the remote. I doubt that there are any switches with 87 ports though.

I doubt that daisy chaining would work, however it could if you'd use different type switches, like 22kHZ and 0/12V types.