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Good downstream, no sync upstream

New Poster

Good downstream, no sync upstream

I know this problem has been dealt with, and I have a tech scheduled to come out, but I'd like to let him or her know what I've done for troubleshooting in advance.  Is there any way to let them know, or do I need to wait until they are at the house and waste time explaining the situation?

 

What I have so far -- brand new equipment for an upgrade from previous service.

Previous service was TV only, and the addressible box never activated, but DTA was sufficient for me.

 

Now, TV (X1 box) won't activate and Internet gateway shows good downstream signal but cannot sync upstream.

 

I'm very certain my inside work is ok, and I can fix it if it isn't.  All I need is an assurance that everything looks good to the tech at the entry point to my house.

 

Internet search suggests the possibility of a line filter left over from analog days, but I'll leave that to the tech.

Diamond Problem Solver

Re: Good downstream, no sync upstream

It’s better to just explain to the on-site tech. Do you have any amps? Post the levels you see on the gateway

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New Poster

Re: Good downstream, no sync upstream

Working from notes (I'm not at home right now):

 

SNR downstream 38.5

Power downstream -1.5 (no amp) +1.5 (with)

1 channel locked downstream, 667 MHz (I think that was the number for freq)

No errors in codewords, either corrected or uncorrected.

 

Upstream is trying to use a freq at 16.something, but not syncing (US/DS rapid blinking on gateway, no power or SNR reported, no channels locked upstream)

 

That's with the gateway directly attached to the cable entering the house, with or without an amp.

 

 

New Poster

Re: Good downstream, no sync upstream

I should have mentioned -- I'm trying to avoid needing to be home for the entire 2 hour window waiting -- I'm hoping the tech can start (and presumably finish) without me there, assuming there's an identifiable problem they can fix outside.

Diamond Problem Solver

Re: Good downstream, no sync upstream

It’s up to you but you should be there for the appointment window. You’re taking a chance it’s not getting fixed if you’re not home.

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New Poster

Re: Good downstream, no sync upstream

Thanks.  I'll be there at some point, but it's really inconvenient for me to be there at the early part of the window.  Like I say, I'm pretty sure my inside plant is ok - nothing at all complicated, and my earlier analog and DTA-supported TV never had any issues.   It's just with the new equipment and service that I can't activate, and everything points to an outdoor issue.

 

I was hoping to be able to give that info to the person coming, but I didn't see any way through the 'My Account' login to actually paste a note to the work order.

 

Diamond Problem Solver

Re: Good downstream, no sync upstream

DTAs can work fine on pretty bad signal/wiring. There isn’t 2 way communication needed like a modem or X1 box.

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New Poster

Re: Good downstream, no sync upstream

Right, that was my point -- analog worked,  the DTA worked (on downstream only); the addressible box at that time never could activate, but I wasn't interested in the services it provided, so I just used the DTA.

 

Now with the numbers I see with a modem I've got to believe the cable itself is good, but something is preventing upstream communication.  Given that I'm checking it about 5 feet from the last junction (a straight-through connector just outside the house) before the cable enters my house, the only possible thing inside could be that 5 feet of cable, and I have a hard time believing that, but if the tech can say for sure it must be the problem, I can replace it myself.

 

I'm just hoping the tech can start without me (if they get there before I get home) and do whatever needs to be done to diagnose outside, and either fix it or get word back to the head-end or wherever else it needs to be fixed.

 

I may be wrong, but I absolutely believe the problem is outside my house, and I don't want to miss getting it fixed because the appointment window starts at 3 and I don't get home before 4:30.

 

I hoped getting that info to the tech would let them at least start without me.