[qwsxz]

What are the symptoms of an overloaded 8-SWM?

I live in an MDU with MFH2. I personally have only one HR21 so I know I only use 2 of the SWM tuners. I was the first one in my building to get upgraded to the SWM about 1.5 months ago. Everything worked great until about 1 week ago when I came home from work (about 5:30PM on a Tues) and my tuners couldn't get a reliable signal. Sometimes tuner one would be at 99%, other times tuner 2 would but never both and the signal strength on the 101/trans3 would fluctuate. If I watched a channel, I would see the directv white and blue default feed with pop music playing in the background. About every 5 min, or if I changed channels, I would see the proper channel, but within 10 seconds, it would pixelate and go the D* + pop music screen. I RBR'd, I unplugged all night, I grounded the COAX, I tried everything mentioned on this forum with no luck. However the problem went away away the next morning when I woke up and I tried a desperate RBR. Then all was fine for the rest of the week. Yesterday (Sunday night), the same thing started happening, but it didn't fix itself by morning. I have a service call in to our installer because I do not have access to the SWM rack, however my theory is that since my install, they have overloaded the SWM and on high viewing nights...like sunday night, my signal goes bonkers.

Does this sound right, or could it be just a bad SWM or a bad HR21? Thanks!

PS. When I do a system test. Most of the time I get both tuners:OK at 0%, but somtime one is at 99%. And about half the time, the LNB Output fails.

 

[texasbrit]

What are the symptoms of an overloaded 8-SWM?

I live in an MDU with MFH2. I personally have only one HR21 so I know I only use 2 of the SWM tuners. I was the first one in my building to get upgraded to the SWM about 1.5 months ago. Everything worked great until about 1 week ago when I came home from work (about 5:30PM on a Tues) and my tuners couldn't get a reliable signal. Sometimes tuner one would be at 99%, other times tuner 2 would but never both and the signal strength on the 101/trans3 would fluctuate. If I watched a channel, I would see the directv white and blue default feed with pop music playing in the background. About every 5 min, or if I changed channels, I would see the proper channel, but within 10 seconds, it would pixelate and go the D* + pop music screen. I RBR'd, I unplugged all night, I grounded the COAX, I tried everything mentioned on this forum with no luck. However the problem went away away the next morning when I woke up and I tried a desperate RBR. Then all was fine for the rest of the week. Yesterday (Sunday night), the same thing started happening, but it didn't fix itself by morning. I have a service call in to our installer because I do not have access to the SWM rack, however my theory is that since my install, they have overloaded the SWM and on high viewing nights...like sunday night, my signal goes bonkers.

Does this sound right, or could it be just a bad SWM or a bad HR21? Thanks!

PS. When I do a system test. Most of the time I get both tuners:OK at 0%, but somtime one is at 99%. And about half the time, the LNB Output fails.

Yes, they could have connected more than eight tuners to an SWM (or someone in one of the other apartments has added tuners without telling anyone). But going to the SWM rack will not tell you anything if the splitter has been installed somewhere else. This IMHO is one of the main drawbacks to using MFH2.

 

[qwsxz]

Yes, they could have connected more than eight tuners to an SWM (or someone in one of the other apartments has added tuners without telling anyone). But going to the SWM rack will not tell you anything if the splitter has been installed somewhere else. This IMHO is one of the main drawbacks to using MFH2.

I understand. But if I had access, I could move my line to one of the other SWMs I know are unused in the closet if in fact my theory about my problem is correct. I am pretty sure in my building instead of doing each new unit install on its own SWM, then doubling up on once all are used once, they are just loading up one SWM at a time which, which in my opinion, would make this problem more likely, especially if unit owners are not only splitting themselves, but also if the install techs aren't labeling the lines with the number of tuners used.

Sorry...i whine.

 

[DirecTv Chicago]

I understand. But if I had access, I could move my line to one of the other SWMs I know are unused in the closet if in fact my theory about my problem is correct. I am pretty sure in my building instead of doing each new unit install on its own SWM, then doubling up on once all are used once, they are just loading up one SWM at a time which, which in my opinion, would make this problem more likely, especially if unit owners are not only splitting themselves, but also if the install techs aren't labeling the lines with the number of tuners used.

Sorry...i whine.

It is far to expensive for a System Operator to install 1 SWM per customer unless the customer is going to pay for the SWM outright. But it is also the job of the SO to mantain accurate records of how many tuners they have installed per SWM. These numbers of course can be changed without the SOs knowledge when a customer installs his own equipment on their own.

Your symptoms does not sounds like an oversubscribed SWM. Main reason being is that if it was an over subscribed SWM that the 2nd tuner would never work not periodical. Someone correct me if I am wrong but in order for a receiver to disassociate from a SWM it must be either powered down for an extended period of time or the receiver unplugged from the coax connection. So unless someone was unplugging the coax connection nightly you should not have service one day on the 2nd tuner and not the next day.

I would not recommend connecting yourself on your own to another SWM as your just going to cause yourself a problem in the future when the SO believes they have two open tuners when they only really have one or none. You may then begin searching for Sat or your neighbors then would.

 

[sylvanir]

Your symptoms does not sounds like an oversubscribed SWM. Main reason being is that if it was an over subscribed SWM that the 2nd tuner would never work not periodical. Someone correct me if I am wrong but in order for a receiver to disassociate from a SWM it must be either powered down for an extended period of time or the receiver unplugged from the coax connection. So unless someone was unplugging the coax connection nightly you should not have service one day on the 2nd tuner and not the next day.

When a SWM capable receiver is connected to the SWM and powered on, the SWM assigns one/two of it's available channels to that tuner (or tuners if the receiver is a dvr) If a receiver is connected that would supass the capability of the SWM, the SWM simply doesn't assign an output channel to that tuner. So, only the first 8 tuners connected and powered on would work. There would not be an intermittent issue.

To me, this sounds more like either a potential grounding issue or possibly a power inserter going haywire. Just my $.02

 

[texasbrit]

When a SWM capable receiver is connected to the SWM and powered on, the SWM assigns one/two of it's available channels to that tuner (or tuners if the receiver is a dvr) If a receiver is connected that would supass the capability of the SWM, the SWM simply doesn't assign an output channel to that tuner. So, only the first 8 tuners connected and powered on would work. There would not be an intermittent issue.

To me, this sounds more like either a potential grounding issue or possibly a power inserter going haywire. Just my $.02

Agree with you about the SWM and its channel assignment. It would appear to be more random if you had a DVR and one tuner was connected OK to the SWM with the other not connected. Then you would appear to be losing signal intermittently, although it would always be on one tuner which does not seem to be the case here.
Although I am not sure this works exactly the way you describe (I had thought the same way you do). It looks like if a tuner "enrolls" with the SWM, and another tuner is already requesting the same transponder channel set, the SWM gives the second tuner the same channel. So if I have both tuners on a DVR set to record from the same transponder block, it only uses one SWM channel.
As a test, I set my three DVRS to record channels from the same transponder block, and tuned my other receiver on the SWM to the same transponder block also. I then used the SWM signal strength screen on the HR21 to see how many SWM channels I was using. The answer was three - one for the transponder block I was tuned to on all the tuners (except 1 - see below) and one for the "shared" data. I could not get all seven tuners on the same block because moving through the signal strength screen to get to the SWM screen screws up one of the tuners, which was why I could not get below three SWM channels..
Anyway, then as I re-tuned each tuner on the other DVRs so it was on a different block of transponders, another SWM channel showed a signal. I could easily demonstrate this using my receiver connected to the SWM - when it was on the same channel as one of the DVR tuners, it did not seem to use a dedicated SWM channel - as soon as I tuned it to a transponder block not being used by anyone else, up popped another SWM channel signal.

This makes the failure modes of the SWM much more complex, because if you have more than eight tuners attached to an SWM they will all appear to work randomly depending on which transponder block they are each currently requesting.

 

[qwsxz]

Ok this morning I could watch one LIL HD channel fine (NBC 5 CHICAGO) on tuner 2. Tuner 1 was completly out and searching for SAT- 771 with the dialog box up on the screen. Every few min the searching for sat on tuner 1 dialog would disappear for 2-3 min. Meanwhile on Tuner 2, the picture and sound is fine. After a few more min, there would be picture breakup/feeze with audio dropout for less than 5 secs on Tuner 2 and the tuner 1 searching box would pop up again. This repeated every several min until I left for work. (About an hour of viewing time.)

At one point the signal in both tuners was lost for 2-3 min. It was right during a commercial which leads me to believe that someone else on the SWM changed channels and transponders during the commercial. This is just a theory though.

After RBR, this scenario could swap tuners or both could be out with a handful of channels getting the D* logo with pop music playing.

The tech is scheduled today and I will post the cause/resolution to the best of my technical ability tomorrow morning.

 

[AntAltMike]

Has anyone scanned the SWM output with a spectrum analyzer to see if there are always nine signals (eight transponders plus a forward control "transponder") being outputted regardless of the tuner loading. If the intermediate frequency transponders only are developed as necessary, then it would be possible to perform experiments that tended to vaildate or disprove certain theories regarding how the SWM assigns transponders to the tuners.

I've never worked on a receiver in SWM configuration. Can anyone post a picture of the "signal test" screen that the receiver develops in SWM signal test, if there is one?

 

[AntAltMike]

I vote that a moderator change the title of this thread to "Oversubscribed SWM symptoms". An overloaded SWM would be one where the preamplification of the LNB signals going into an SWM was excessive, to the point at which it caused debilitating intermodulation distortion.

 

[scottz46]

I also live in in mdu and had the same problem recently. I have five tuners going and the installers overloaded the swm with other units. I was given my own when they made the service call. Just have you installer right on the swm with a sharpie that you have two tuners when they come out so u dont run into this problem again.

 

[texasbrit]

Has anyone scanned the SWM output with a spectrum analyzer to see if there are always nine signals (eight transponders plus a forward control "transponder") being outputted regardless of the tuner loading. If the intermediate frequency transponders only are developed as necessary, then it would be possible to perform experiments that tended to vaildate or disprove certain theories regarding how the SWM assigns transponders to the tuners.

I've never worked on a receiver in SWM configuration. Can anyone post a picture of the "signal test" screen that the receiver develops in SWM signal test, if there is one?

Here's the HR21 SWM screen, with six tuners all tuned to the same transponder. There's one SWM channel for the transponder, one for the tuner that is on another transponder (the one driving the signal strength screens) and one for the shared data - three SWM channels in total, even though I have six/seven live tuners connected.

 

[qwsxz]

Installer arrived a bit early. The initial diagnosis was a bad HR21. I convinced him to check out the closet just to make sure.

Now I will try to describe what the problem was and how it was resolved as technically accurate as I can with very little knowledge of the subject, so please bare with me.

Problem possibility 1:

The tech asked if I was getting internet service from them as well through the one COAX that is shared with the sat signal. I am and told him so. He said he knew exactly what the problem was and his explained that the original installer diplexed the internet signal into the line after the SWM instead of using the internet port on the SWM itself. Because of the low frequency, it was conflicting with the LNB output which directs the transponder selection on the SWM.

Problem possibility 2:

While looking in the closet I asked how they know how many tuners are used by each wire that is connected to the SWM. I saw five going in the SWM I was hooked up to. The tech claimed that he had come after the first installer had started hooking up units and noticed the first installer didn't label the unit drops with their tuner usage. He spent an afternoon labeling them all. I don't know how he did it accurately, but my wire had a "2 tuners" label on it which is accurate. But he admitted that even he wouldn't know if a unit owner got their own equipment and installed it without calling them.


Solution:

Because there were 16 total SWMs in the closet and only 1 was being used by 5 wires, I asked the tech if he could plug my unit into an unused SWM just to make sure it wasn't overloaded. He put me on the last one which will hopefully keep me in the clear for a while. He also got rid of the internet diplexer and it appeared that he put the internet feed directly into the SWM. I couldn't ask to many questions because of a language barrier, but again, this is what I think I understood and saw. I do know for sure that I don't have diplexer for internet in the closet anymore.

No changes were made in the unit.


Result:

The internet is still up but is a tad slower. I restarted everything from the wall out and hopefully over the next few days it will speed up again, but as long as I have some internet for mail, I am fine.

My HR21 is working great after one RBR. It booted up faster than I remember it has ever before and I am getting between 96-100 on all 9 of the SWM transponders on both tuners. I am even getting signals on 99(c) which I think is the new D11!

I still think that it was an overloaded SWM issue, but I don't know for sure. I don't know why my setup would work for a over a month and then just poop out if the problem was in fact the internet diplexing issue.

 

[doctor j]

Installer arrived a bit early. The initial diagnosis was a bad HR21. I convinced him to check out the closet just to make sure.

Now I will try to describe what the problem was and how it was resolved as technically accurate as I can with very little knowledge of the subject, so please bare with me.

Problem possibility 1:

The tech asked if I was getting internet service from them as well through the one COAX that is shared with the sat signal. I am and told him so. He said he knew exactly what the problem was and his explained that the original installer diplexed the internet signal into the line after the SWM instead of using the internet port on the SWM itself. Because of the low frequency, it was conflicting with the LNB output which directs the transponder selection on the SWM.

Problem possibility 2:

While looking in the closet I asked how they know how many tuners are used by each wire that is connected to the SWM. I saw five going in the SWM I was hooked up to. The tech claimed that he had come after the first installer had started hooking up units and noticed the first installer didn't label the unit drops with their tuner usage. He spent an afternoon labeling them all. I don't know how he did it accurately, but my wire had a "2 tuners" label on it which is accurate. But he admitted that even he wouldn't know if a unit owner got their own equipment and installed it without calling them.

Solution:

Because there were 16 total SWMs in the closet and only 1 was being used by 5 wires, I asked the tech if he could plug my unit into an unused SWM just to make sure it wasn't overloaded. He put me on the last one which will hopefully keep me in the clear for a while. He also got rid of the internet diplexer and it appeared that he put the internet feed directly into the SWM. I couldn't ask to many questions because of a language barrier, but again, this is what I think I understood and saw. I do know for sure that I don't have diplexer for internet in the closet anymore.

No changes were made in the unit.

Result:

The internet is still up but is a tad slower. I restarted everything from the wall out and hopefully over the next few days it will speed up again, but as long as I have some internet for mail, I am fine.

My HR21 is working great after one RBR. It booted up faster than I remember it has ever before and I am getting between 96-100 on all 9 of the SWM transponders on both tuners. I am even getting signals on 99(c) which I think is the new D11!

I still think that it was an overloaded SWM issue, but I don't know for sure. I don't know why my setup would work for a over a month and then just poop out if the problem was in fact the internet diplexing issue.

Glad things worked out.
My information suggests that diplexing after the SWM is not an issue!
May even be preferable if several FMC-6 cabinets are used due to fixed applification of the "OTA" signals 5-860 MHz, which is where the cable internet is.

Doctor j

 

[texasbrit]

Installer arrived a bit early. The initial diagnosis was a bad HR21. I convinced him to check out the closet just to make sure.

Now I will try to describe what the problem was and how it was resolved as technically accurate as I can with very little knowledge of the subject, so please bare with me.

Problem possibility 1:

The tech asked if I was getting internet service from them as well through the one COAX that is shared with the sat signal. I am and told him so. He said he knew exactly what the problem was and his explained that the original installer diplexed the internet signal into the line after the SWM instead of using the internet port on the SWM itself. Because of the low frequency, it was conflicting with the LNB output which directs the transponder selection on the SWM.

Problem possibility 2:

While looking in the closet I asked how they know how many tuners are used by each wire that is connected to the SWM. I saw five going in the SWM I was hooked up to. The tech claimed that he had come after the first installer had started hooking up units and noticed the first installer didn't label the unit drops with their tuner usage. He spent an afternoon labeling them all. I don't know how he did it accurately, but my wire had a "2 tuners" label on it which is accurate. But he admitted that even he wouldn't know if a unit owner got their own equipment and installed it without calling them.

Solution:

Because there were 16 total SWMs in the closet and only 1 was being used by 5 wires, I asked the tech if he could plug my unit into an unused SWM just to make sure it wasn't overloaded. He put me on the last one which will hopefully keep me in the clear for a while. He also got rid of the internet diplexer and it appeared that he put the internet feed directly into the SWM. I couldn't ask to many questions because of a language barrier, but again, this is what I think I understood and saw. I do know for sure that I don't have diplexer for internet in the closet anymore.

No changes were made in the unit.

Result:

The internet is still up but is a tad slower. I restarted everything from the wall out and hopefully over the next few days it will speed up again, but as long as I have some internet for mail, I am fine.

My HR21 is working great after one RBR. It booted up faster than I remember it has ever before and I am getting between 96-100 on all 9 of the SWM transponders on both tuners. I am even getting signals on 99(c) which I think is the new D11!

I still think that it was an overloaded SWM issue, but I don't know for sure. I don't know why my setup would work for a over a month and then just poop out if the problem was in fact the internet diplexing issue.

Diplexing after the SWM should work just as well as diplexing using the SWM, unless he used one of the models of diplexer that does not seem to pass the 2.3GHz signal that the tuners use to communicate with the SWM. But that would be unlikely if he was using the same model diplexer that is being used to split the internet cable off from the sat signal, because those would not work either.

BUT: If you are getting signals on all nine SWM channels that means there are eight tuners attached to your SWM!!

EDIT: Let me clarify that. If you are on your own SWM8 and you only have one HR21 you should see two or three active SWM channels, two for tuners (one if they are on the same transponder) and one for the shared channel. If you are seeing nine channels, you are NOT on your own MDU and therefore someone has probably screwed up the cable IDs somewhere.

 

[texasbrit]

FYI, I sent a PM to dave29, many people have purchased their SWMs from him. He confirmed that the tuners seem only to get a separate SWM channel if the transponder they need is not already on one of the other SWM channels.
Let me quote from his PM: QUOTE I have actually had 16 tuners hooked up to one of my swm8's and when they are all on the same channel it works fine. If you even change the channel on 1 tuner..... then everything goes haywire. so my theory is........ if every tuner is on the same transponder then everything is fine. if you had 8 dvrs hooked up and you used a combination of channels (but not to exceed 8 transponders) it works fine as well. UNQUOTE

dave - thanks for the confirmation.

 

[DirecTv Chicago]

I also live in in mdu and had the same problem recently. I have five tuners going and the installers overloaded the swm with other units. I was given my own when they made the service call. Just have you installer right on the swm with a sharpie that you have two tuners when they come out so u dont run into this problem again.

Most installers should and I would imagine do indicate on the cabling how many tuners are being used. But all it takes is for one missed receiver or a tenant that installs their own receiver to change those numbers. Since there are only 8 tuners 1 is alot.

You take the good with the bad when it comes to MFH2. Customers just need to understand that their are some growing pains with this system just as there are when changing from windows 2000 to XP but in the end it was a much better system.

 

[Grydlok]

Most installers should and I would imagine do indicate on the cabling how many tuners are being used. But all it takes is for one missed receiver or a tenant that installs their own receiver to change those numbers. Since there are only 8 tuners 1 is alot.

You take the good with the bad when it comes to MFH2. Customers just need to understand that their are some growing pains with this system just as there are when changing from windows 2000 to XP but in the end it was a much better system.

Going from Windows 2000 to XP wasn't anything. They were Similar. Going from 98SE to XP was different.

 

[Tom Robertson]

<Mod note> Title changed.

I'll have to try the many tuners on one transponder trick. I think I have enough tuners to run the test...

Glad you found a tech that could solve the problem!

As noted, the diplexer could have been the problem if it wasn't passing the frequency ranges necessary for two bidirectional communications: the internet return channel and tuner control of the SWM. I've seen similar intermittent problems with some of the diplexers I've tried.

Cheers,
Tom

 

[veryoldschool]

As noted, the diplexer could have been the problem if it wasn't passing the frequency ranges necessary for two bidirectional communications: the internet return channel and tuner control of the SWM. I've seen similar intermittent problems with some of the diplexers I've tried.

Cheers,
Tom

The loss through one diplexer may not be enough to cause the problem, but the loss through two may be marginal.
As for the Internet speed slowing down: I hope it speeds up, but the loss of the SWM's internal diplexer may be the cause, and if so, it won't speed up.

 

[bobnielsen]

I recall reading in another thread that the internal diplexer didn't work very well with VHF-low OTA signals. Perhaps that loss could affect the internet connection.