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**bel71281** · March 16th, 2008

c/p from eeqmc2

I decided to post this info to help the community out:
After reading some great info from several sites and doing my own testing here is what i found out bout the dpp44 switch which can help some people.

The dpp44 and dp34 switches must has an internal switch table that takes advantage of diseqc 2.0. Dp twins and quad which are the most utilized dps in todays intallations come in with either 2 or 4 ports. Each port has a built in diseqc switch. So each port connects to both sats (usually 110, 119). The interesting thing is that echos*ar setups this ports and thus the internal switch so that when the lnbs are connected to a dpp44/dp34 switch they have the following default states (initial switching configuration)

dp twin:
Port 1 is port 119
port 2 is port 110

Remember each port is connected to its own diseqc internal switch. These switches must likely are 2x1 switches.These are the states of those internal switches.

dp quad:
port 1 is port 119
port 2 is port 110
port 3 is port 119
port 4 is port 110

so the quad has 4 built in diseqc switches with those default settings.

Now when you connect say a twin lnb port 1 to the dpp44 sat 1 port, twin lnb port 2 to dpp44 sat 2 port and you power up the dpp44, it performs a check switch (which resets the internal switches to the default states) and it knows what satellite is on what sat port, ie sat port1 is 119 with twin or quad port 1, and sat port 2 is 110 with twin or quad port2. After that the dpp44 doesnt really use those internal switches for the receiver ports.It uses those defaults states of the switches. When any receiver is connected to any dpp44 receiver port, the dpp44 only switches between say sat port 1 or sat port 2 inside the switch depending on what the receiver is requesting. This is why if you want a diseqc switch connected to receiver dpp ports and you have a twin or quad you must connect 2 cables to port 1 and port 2 of the switch.So when the receiver asks for a different sat, the dpp 44 only switches to the appropriate sat port, it doesnt "pass thru" a diseqc command to switch those internal switches.Note that in direct connections to a dp twin or quad you only need one cable (bet receiver and lnb) or (diseqc switch and lnb).

Now here is really i call new info: the dpp44 (and dp34) have trunking ports on the side. I found out that when i connected say a single trunking port to a 4x1 switch (single cable), i could then watch both sat locations without a problem.In another words, those trunking ports allow the diseqc commands to be propagated to the internal diseqc switch (almost as each trunking port has direct connection to the internal switches in the lnbs), so the states of those switches were changed by the request from the trunk ports.I did test this by having say one pansat 3500 connected to receiver port 1 and having say another pansat connected to trunking port 1. Initially all is good, say box 1 (off the receiver port) is on 119 and box 2 (off the trunk port is on 110).Now lets say i switched box 2 to 119. The dpp44 then allows the pass thru sat 1 port of the diseqc command to switch to 119.Sat 1 port is on 119 (internal switch is on 119) so no problem.But then i go back to 110 on box 2, now the dpp 44 allows the request to sat port 1 for 110, the internal diseqc switch in port 1 switches now to 110.Now box 1 which was looking at 119 via sat port 1, is getting 110, so you loose the image. So for the receiver ports, those internal lnbs switches inside the dp lnbs are not touched. So switching channels on box 1 didnot have any effect on box 2 as it should.
Oh one way to recover is either turn the switch power supply off and on or perform a check switch from a sub ird.The check switch procedure reinitialized the switches to the original configuration.So in this case i would loose signal on box 2 but not for long as i do a request to change channels and it will switch no problem (it changing the default state of the internal switches again).But the cycle then continues and there is no way around it.

I am not sure why they designed like that, perhaps, so that when two dpp44 switches are trunked together, the 2nd switch can get the lnb configuration.If used as in echstar procedure, then once the 2ns switch knows that configuraiton it doesnt have to communicate upstream again.

Good observation.
The check switch does more than reset the DiSEqC switches on each port but that is basically correct. The key to everything you stated is the fact you are always using the default state of the LNB port, one never changes those built in DiSEqC switches when using a DP34 and a DP44 switch.
The only time the DiSEqC switches in the 34 or 44 is changed is when your channel says it needs this sat or that sat. The check switch sets the default state of those switches and monitors the change if there is a change based on what channel is requested by port.

You are misinterpreting the port requirements for both the DP34 and the DP44 when you state certain ports must be used for 119 or 110. Neither switch cares what is on what port providing the correct default port is present somewhere on the switch. Convention and consistency is why we put 119 on port 2 and 110 on port 1; just easier to remember if you always do it the same way.
Since you have the switch you can prove this to yourself by taking 119 and putting it on port 3. Now change your menu to show 119 on port 3 and you will see you have both 110 and 119 without them being on port 1 and 2.

It is easy to confuse this characteristic so don't feel bad about it.
The reason you set the DiSEqC switches to the default port of the switch is so any DP LNB will be seen when connected to any port. If you use a DP dual (having no internal switches) the default port allows that signal to pass to the data buss.

If you add another Quad or Twin to ports 3 and 4 (adjust menu accordingly) say for Bev 82 and 91 and you do not pay attention to which goes where, then it is possible that the default 91 port (Twin) could be placed on an open port of the DP44. Resetting the defaults of the DP44 makes all ports normally closed for access to the data buss waiting for channel data to switch the internal DiSEqC to the correct data buss. Again we use the defaults of the LNB to supply a constant source of 82 and 91, no matter which port they are tied to, and using the DiSEqC commands to toggle between those two sats' data busses.

March 16th, 2008	#1 (permalink)
bel71281 IM BACK Join Date: Mar 2006 Posts: 2,542 Thanks: 366 Thanked 1,700 Times in 758 Posts Rep Power: 168	dpp44 and dp34 switch operation c/p from eeqmc2 I decided to post this info to help the community out: After reading some great info from several sites and doing my own testing here is what i found out bout the dpp44 switch which can help some people. The dpp44 and dp34 switches must has an internal switch table that takes advantage of diseqc 2.0. Dp twins and quad which are the most utilized dps in todays intallations come in with either 2 or 4 ports. Each port has a built in diseqc switch. So each port connects to both sats (usually 110, 119). The interesting thing is that echos*ar setups this ports and thus the internal switch so that when the lnbs are connected to a dpp44/dp34 switch they have the following default states (initial switching configuration) dp twin: Port 1 is port 119 port 2 is port 110 Remember each port is connected to its own diseqc internal switch. These switches must likely are 2x1 switches.These are the states of those internal switches. dp quad: port 1 is port 119 port 2 is port 110 port 3 is port 119 port 4 is port 110 so the quad has 4 built in diseqc switches with those default settings. Now when you connect say a twin lnb port 1 to the dpp44 sat 1 port, twin lnb port 2 to dpp44 sat 2 port and you power up the dpp44, it performs a check switch (which resets the internal switches to the default states) and it knows what satellite is on what sat port, ie sat port1 is 119 with twin or quad port 1, and sat port 2 is 110 with twin or quad port2. After that the dpp44 doesnt really use those internal switches for the receiver ports.It uses those defaults states of the switches. When any receiver is connected to any dpp44 receiver port, the dpp44 only switches between say sat port 1 or sat port 2 inside the switch depending on what the receiver is requesting. This is why if you want a diseqc switch connected to receiver dpp ports and you have a twin or quad you must connect 2 cables to port 1 and port 2 of the switch.So when the receiver asks for a different sat, the dpp 44 only switches to the appropriate sat port, it doesnt "pass thru" a diseqc command to switch those internal switches.Note that in direct connections to a dp twin or quad you only need one cable (bet receiver and lnb) or (diseqc switch and lnb). Now here is really i call new info: the dpp44 (and dp34) have trunking ports on the side. I found out that when i connected say a single trunking port to a 4x1 switch (single cable), i could then watch both sat locations without a problem.In another words, those trunking ports allow the diseqc commands to be propagated to the internal diseqc switch (almost as each trunking port has direct connection to the internal switches in the lnbs), so the states of those switches were changed by the request from the trunk ports.I did test this by having say one pansat 3500 connected to receiver port 1 and having say another pansat connected to trunking port 1. Initially all is good, say box 1 (off the receiver port) is on 119 and box 2 (off the trunk port is on 110).Now lets say i switched box 2 to 119. The dpp44 then allows the pass thru sat 1 port of the diseqc command to switch to 119.Sat 1 port is on 119 (internal switch is on 119) so no problem.But then i go back to 110 on box 2, now the dpp 44 allows the request to sat port 1 for 110, the internal diseqc switch in port 1 switches now to 110.Now box 1 which was looking at 119 via sat port 1, is getting 110, so you loose the image. So for the receiver ports, those internal lnbs switches inside the dp lnbs are not touched. So switching channels on box 1 didnot have any effect on box 2 as it should. Oh one way to recover is either turn the switch power supply off and on or perform a check switch from a sub ird.The check switch procedure reinitialized the switches to the original configuration.So in this case i would loose signal on box 2 but not for long as i do a request to change channels and it will switch no problem (it changing the default state of the internal switches again).But the cycle then continues and there is no way around it. I am not sure why they designed like that, perhaps, so that when two dpp44 switches are trunked together, the 2nd switch can get the lnb configuration.If used as in echstar procedure, then once the 2ns switch knows that configuraiton it doesnt have to communicate upstream again. Good observation. The check switch does more than reset the DiSEqC switches on each port but that is basically correct. The key to everything you stated is the fact you are always using the default state of the LNB port, one never changes those built in DiSEqC switches when using a DP34 and a DP44 switch. The only time the DiSEqC switches in the 34 or 44 is changed is when your channel says it needs this sat or that sat. The check switch sets the default state of those switches and monitors the change if there is a change based on what channel is requested by port. You are misinterpreting the port requirements for both the DP34 and the DP44 when you state certain ports must be used for 119 or 110. Neither switch cares what is on what port providing the correct default port is present somewhere on the switch. Convention and consistency is why we put 119 on port 2 and 110 on port 1; just easier to remember if you always do it the same way. Since you have the switch you can prove this to yourself by taking 119 and putting it on port 3. Now change your menu to show 119 on port 3 and you will see you have both 110 and 119 without them being on port 1 and 2. It is easy to confuse this characteristic so don't feel bad about it. The reason you set the DiSEqC switches to the default port of the switch is so any DP LNB will be seen when connected to any port. If you use a DP dual (having no internal switches) the default port allows that signal to pass to the data buss. If you add another Quad or Twin to ports 3 and 4 (adjust menu accordingly) say for Bev 82 and 91 and you do not pay attention to which goes where, then it is possible that the default 91 port (Twin) could be placed on an open port of the DP44. Resetting the defaults of the DP44 makes all ports normally closed for access to the data buss waiting for channel data to switch the internal DiSEqC to the correct data buss. Again we use the defaults of the LNB to supply a constant source of 82 and 91, no matter which port they are tied to, and using the DiSEqC commands to toggle between those two sats' data busses.