Is DiSEqC a 1-way or 2-way Protocol?

[cyberham]

I've mentioned in other threads I started having trouble accurately and reliably motoring to a satellite after installation of a PLL LNB. Likely the cause is related to an overly-long run of RG-6 (200 feet). I've noticed that using "Goto Reference" and then allowing USALS to motor back to a sat location seems much more reliable than simply directing the motor directly to a satellite. Why is that? Could this be due to the fact that using Reference is a 1-way command whereas motoring to a satellite requires 2-way communication between motor and receiver, and therefore has a higher risk of commands being lost in the noise?

 

[FaT Air]

USALS is not a DiSEqC protocol.* USALS, I.E. 1.3 as it has been sometimes called/labeled, is not eutelsat endorsed*
DiSEqC 1.x is one way, DiSEqC 2.x is two way. A DiSEqC 1.x command issued by a receiver is = to a DiSEqC 2.x command. The only difference is a 1.x receiver is deaf to any return ACK by a 2.x component on the coax. Then their is the question of what the "compatible with" infers. Does that 2.x switch just respond to the command issued, (which is 1.x in reality) passively pass 2.x ACK's to the receiver from actual 2.x components further out from the receiver, or send ACK's itself back to the receiver.
To what level is the switches 'compatibility'?

A 1.x receiver is actually 2.x 'Compatible' as it can send the commands.
The question of utilization of the ACK's by the receiver. Resending the command until a proper ACK is received, and timing out to an error to be displayed? Or simply, to what level is the Receivers compatibility?
ACK=acknowledgement sent by the switch/lnb, etc. to the receiver in response to a command issued.
*http://www.eutelsat.com/en/support/technical-support/diseqc.html

I'd put a "T" out at the motor and watch the voltage as it moves the dish. It doesn't take much in the way of corrosion of the aluminum shield to cause a substantial voltage drop. The center conductor and connectors could look 'fine' but the outer shield could be 'dust'. Could be a nick in the sheathing 'half way out' to the dish?
Possible solutions: 1- Move the dish when on, and to, an H polarity channel. (Higher voltage) IIRR, the microHD does this automatically.
2- Supply motor with 'outboard' power so it's not dependent on the LNB voltage.
3-Replace Coax.
I absolutely believe the more current you run thru coax, the faster, and more devastating, the effects of corrosion are.

 

[cyberham]

Let me digest all this. It sounds like there's more nattering than on The View.

Added: microHD is USALS/DiSEqC 1.2 for motor control. Perhaps if it was 2.0 my issue would dissolve. Any missed commands would not be ACKed and would be resent by the receiver. Of course, the motor would need to be 2.0 too, which it isn't.

 

[FaT Air]

?I think the inference is the microHD is USALS or DiSEqC 1.2 (motor control) DiSEqC = Eutalsat , USALS = STAB
Don't know if USALS has a ACK feature. But if the motor were 2.2 and the receiver implemented the ACK of the 2.x feature set you'd get resend of the DiSEqC command OR, I would think, an error indication if there's a problem.

 

[updatelee]

DISEQC *can* be a two way protocol but I have yet to see a single receiver / pc tuner that actually implements it.

UDL

 

[primestar31]

DISEQC *can* be a two way protocol but I have yet to see a single receiver / pc tuner that actually implements it.

UDL

There's a thread on here somewhere in the last year, that a guy who has a STAB motor and a MicroHD reported in a post that the MicroHD receiver and that particular motor were communicating back and forth for sure. I'll attempt to find it.

Found it: http://www.satelliteguys.us/threads/289022-Setup-USALS-Issue?p=2923835#post2923835

 

[updatelee]

Maybe I'm blind but I don't see where it's confirmed that it's receiving diseqc commands

UDL

 

[cyberham]

...Found it: http://www.satelliteguys.us/threads/289022-Setup-USALS-Issue?p=2923835#post2923835

After reading this thread, and in particular this post, I recalled something from my past when I was using an S9. I seemed to find if I combined using USALS with DiSEqC motoring, my motor got confused. Lately, I have been using all USALS except for 15W where I use DiSEqC since at that eastern edge of the arc, my USALS does not precisely point the dish. So just now I changed 15W to USALS also. Now all sats enabled in the Satellite List are set for USALS. Is it a coincidence that suddenly my motor is now acting like the good old days and going to each sat I command it to go to? I haven't seen this precise action since I installed my new PLL LNB.

Question: Is it mandatory that all sats be set for either USALS or DiSEqC, but not a combination of both?

 

[phlatwound]

...Question: Is it mandatory that all sats be set for either USALS or DiSEqC, but not a combination of both?

No, you can use a combination.

I have always used Diseqc for 30W, and USALS for everything else, and it works flawlessly. Done it with several different receivers.

 

[cyberham]

No, you can use a combination.

Glad to hear this confirmed. This makes logical sense.

 

[jorgek]

After reading this thread, and in particular this post, I recalled something from my past when I was using an S9. I seemed to find if I combined using USALS with DiSEqC motoring, my motor got confused. Lately, I have been using all USALS except for 15W where I use DiSEqC since at that eastern edge of the arc, my USALS does not precisely point the dish. So just now I changed 15W to USALS also. Now all sats enabled in the Satellite List are set for USALS. Is it a coincidence that suddenly my motor is now acting like the good old days and going to each sat I command it to go to? I haven't seen this precise action since I installed my new PLL LNB.

Question: Is it mandatory that all sats be set for either USALS or DiSEqC, but not a combination of both?

Regarding the new found precise tracking of the S9, are you using the same firmware today that you were when the s9 was giving you headaches?
The change in LNBF should not be an issue. I have used 4 different brands of KU LNBFs with my motor without any issues.

 

[cyberham]

Not using the S9 today. I was referring to last year when I used it. Have only been using new PLL LNB with microHD. The PLL LNB is not at all to blame, but its slightly higher current demand than a non-PLL version may have brought forward hidden issues. Over the past 2 years I've used 3 non-PLL LNBs and never had this much trouble with the motor. But I think the motor has been under stress by the little bit heavy dish. Someday I'll swap it for an HH120 and likely all will be fine.

 

[cyberham]

My receiver claims to have "Current Protection (thermal reset)" for the LNB IN port. I am wondering if this may be why I am at times feeling that my dish motor has gone stupid and won't move. There are times when I can't bump my dish back and forth using diseqc commands to fine tune a signal. The dish just won't move at those times. This usually occurs after monkeying a lot moving the dish across wide angles on the arc such as from 103W to 15W. Then I give up, go away, come back later and the motor has magically moved to the correct location via USALS. Perhaps the thermal reset timed out, things cooled, and then the motor worked again reliably.

 

[updatelee]

next time it happens just pop a volt meter on there and see whats happening

UDL

 

[cyberham]

I will.