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My Signals and T3 TImeouts

I was having issues with my connection. TWC came out and said too much power was coming into my condo unit. Tap is right outside of unit, where connection comes into condo.

 

Technician told me they changed fittings and such outside, they called bucket truck who made adjustment at pole and tap to lower downstream levels. Levels came down from +12-13, to +4-7. Internet seems better, but upstream signal increased from 47 to around 52 and that started causing issues. Two Upstream channels wouldn’t lock.

 

They came out out again and tech took off the 3-way splitter first tech installed and installed a 2-way splitter. That dropped upstream to around 47 again, but then my downstream increased slightly.

 

Then other day noticed spectrum trucks working around neighborhood and all of a sudden upstream drops to 42.5-43.5. It’s been solid that way for a few days now. From what I understand, that’s a better signal for upstream.

 

This is is my current setup:

 

Cable from wall to 2-way splitter, then splitter  branches off to DVR and Cable modem. They added a filter to back of cable modem. We have a small box in another room that just plays back the DVR recordings. Cable modem is a Technicolor TC8717t. I’ve already set all of MsRaye’s recommended settings for the all-in-ones.

 

I do get my full speeds consistently 70/6.

 

I do see 3-4, T-3 timeouts a day.

 

Should I just give it some time, since they might be working things out in this area?

 

Thank you.

 

22 REPLIES
Established Sharer

Re: My Signals and T3 TImeouts

That looks like a MoCA filter for the whole home DVR service. What is the coax/splitter situation from the wall outlet in question backwards to the main line? Is there an amp?

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Re: My Signals and T3 TImeouts


reds91185 wrote:

That looks like a MoCA filter for the whole home DVR service. What is the coax/splitter situation from the wall outlet in question backwards to the main line? Is there an amp?


Thanks. Not sure.

 

They replaced an old “crimped” fitting behind the wall plate and replaced stuff outside at the tap. Later Truck came out and he did something at tap as well. Said he did something at pole too? Everything outside is closed up.

 

All I know about setup is what I posted from wall plate on.

 

Are the signals off in your opinion?

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Re: My Signals and T3 TImeouts

I called TWC again and got Tier 3 support.

TWC/Spectrum sending someone out again today. Said they are working in area and having issues in area, but that my downstream were borderline to high and they are seeing errors. Will keep this thread updated with results and when it’s solved. Thanks.
Expert

Re: My Signals and T3 TImeouts

Your photo's don't paste here, copy and paste the pages,

US should be between +30 and +50 dBmv.

DS must be between -8 and +8 dBmv.

 disregard any manufacturers specs as they are outside TWC's actual noise and distortion levels.  US of +52 is on the edge of not working with no headroom left for levelling.

Too high or too low DS also puts the modem into kinda works but with a lot of errors, that slows down you and everyone else on the node.

 

 

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Re: My Signals and T3 TImeouts

Thanks MsRaye. I have seen some of these downstream numbers over 10-11 dBmV.

 

Downstream Channel Bonding

 

Value Index  1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

 

Lock Status  Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked

 

Frequency 645 MHz 561 MHz 567 MHz 573 MHz 579 MHz 585 MHz 591 MHz 597 MHz 603 MHz 609 MHz 615 MHz 621 MHz 627 MHz 633 MHz 639 MHz 555 MHz

 

SNR 40.1 dB 39.6 dB 39.6 dB 39.6 dB 39.6 dB 39.6 dB 39.6 dB 39.6 dB 39.8 dB 39.7 dB 39.6 dB 39.7 dB 39.8 dB 39.8 dB 39.9 dB 39.6 dB

 

Power 10.0 dBmV 6.9 dBmV 7.0 dBmV 7.1 dBmV 7.4 dBmV 7.5 dBmV 7.7 dBmV 7.9 dBmV 8.2 dBmV 8.2 dBmV 8.2 dBmV 8.4 dBmV 8.8 dBmV 9.1 dBmV 9.6 dBmV 6.9 dBmV

 

Modulation 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM

 

Upstream Channel Bonding Value

 

Index 1 2 3 4


Lock Status Locked Locked Locked Locked


Frequency 24.2 MHz 19.4 MHz 30.6 MHz 37.0 MHz


Symbol Rate 5120 Ksym/sec 2560 Ksym/sec 5120 Ksym/sec 2560 Ksym/sec


Power Level 43.5 dBmV 43.5 dBmV 43.5 dBmV 43.5 dBmV


Modulation ATDMA TDMA ATDMA ATDMA


Channel ID 2 1 3 4

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Re: My Signals and T3 TImeouts

Spectrum Tech checked signals. Said some were high and out of range.

 

He installed a 3-way splitter and called it a day.

 

New signals below.

 

Downstream Channel Bonding Value

 

Index

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

 

Lock Status

Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked

 

Frequency

633 MHz 561 MHz 567 MHz 573 MHz 579 MHz 585 MHz 591 MHz 597 MHz 603 MHz 609 MHz 615 MHz 621 MHz 627 MHz 555 MHz 639 MHz 645 MHz

 

SNR

40.7 dB 40.7 dB 40.5 dB 40.5 dB 40.6 dB 40.6 dB 40.4 dB 40.5 dB 41.0 dB 41.1 dB 41.0 dB 40.7 dB 40.7 dB 40.6 dB 40.5 dB 40.7 dB


Power

5.7 dBmV 4.3 dBmV 4.2 dBmV 4.3 dBmV 4.6 dBmV 4.6 dBmV 4.6 dBmV 4.8 dBmV 5.4 dBmV 5.6 dBmV 5.6 dBmV 5.5 dBmV 5.6 dBmV 4.3 dBmV 5.7 dBmV 5.9 dBmV


Modulation

256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM

 

Upstream Channel Bonding Value


Index

1 2 3 4

 

Lock Status

Locked Locked Locked Locked


Frequency

30.6 MHz 24.2 MHz 19.4 MHz 37.0 MHz


Symbol Rate

5120 Ksym/sec 5120 Ksym/sec 2560 Ksym/sec 2560 Ksym/sec

 

Power Level

45.5 dBmV 46.8 dBmV 47.0 dBmV 45.5 dBmV

 

Modulation

ATDMA ATDMA TDMA ATDMA

 

Channel ID

3 2 1 4

Established Sharer

Re: My Signals and T3 TImeouts

Your levels are now good in both directions.  Keeep a copy for the next time you need to call out a tech.  This will be your example of what your normal good working signal looks like.

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Re: My Signals and T3 TImeouts

Thank you, karlbeckman. Question.

 

What are considered normal fluctuations of the upstream and downstream power signals?

Expert

Re: My Signals and T3 TImeouts

DS should remain constant... If you see step changes in all the channels, there is a problem with a connection or splitter changing impedance and that affects the other ports on the splitter. DS uses an ALC channel to regulate levels in most systems.. Some might do a thermal ALC.

US however has no ALC and will vary a little over temperature, usually it goes up a couple DB when temps drop from 70 degrees to below 20 degrees.

Both directions can handle a slow change of +- 3 dB , any more will cause the modem to reset to try to relevel itself with the CMTS at the head end.

 Splitters only have good port isolation when terminated with a 75 ohm load, some will result in a 5 dB change when another port is shorted or openned.

 Anything intermittent usually results in an ingress point from FM radio, aircraft, radar, 4G lte, broadcast TV, business/public service radio....

As you can see, lowering your DS below 8 dB actually raised your s/n by a half dB.

 S/N below 35 dB results in impairment, errors and s/n below 32 dB is where qam 256 no longer works.   All manufacturers specs are in lab conditions and real world is  3-10 dB worst.

 Sorry if the above is too technical, But myself and Karl have been in the RF industry for decades and back in the vacuum tube days...