Cox → Re: [NV] Heat Throwing Off Modem Signal Levelthe center s?

Temperature changes (high heat, very cold) will affect dwnstream signal but not upstream. Upstream variations means attenuation on low frequencies, caused by corossion, bad connector (partially short) or loose connector, cable squirrel chew, staple in cable, bad tap... Upstream isn't suppose to change much... An aluminium braid lost inside a brand newconnector touching the center pin can cause 10 dB upstream variation...

Extreme heat like they have had in Las Vegas recently will cause many of the very things you mention to happen. Your's is really the best explanation so far. I have found that corroded connections are usually the culprit. The metals expanding in the heat exaggerate the corrosion and line resistance in the upstream frequency range increases and in turn the modem ups it's output power to compensate.

I've found a shotgun approach by replacing any connectors, barrels and splitters located outside will usually cure the issue.

even with all the cable lines and splitters inside and outside the home being new?

less than a year

Yes. Partially because it's quick and the least expensive but it's also the culprit much more often than not.

Hopefully your tech comes at the hottest part of the day. If he does the connection replacement first, the modem upstream power will show an immediate improvement if it has been solved.

If not then you move on to checking tap and lines. Connections on the tap are the next most likely culprits.

that is the thing it is not a consistent number it varies a lot and is very random at what times it happens whether it be day or night

and on days like yesterday it did not change much only plus or minus like .3dBmv which i would say is normal but on other days like Friday Saturday and Sunday where it change anywhere from 5dBmv to 15dBmv

One word: Wrong

cox tech came out today and the signals were spiked while he was here the modem and the hd boxes were all failing

so he plug every cable into his meter and tested every line in the home and at the street including the tap and there was no interference

and he saw that the neighbors signal was flucuating just like mine so he turned it over to maitence and we will see what happens tomorrow

2 words: 100% correct

As in, News is 100% correct

Attenuation due to heat affects the higher downstream frequencies, not the lower upstream frequencies. Since the modems downstream levels were unaffected that rules out attenuation due to heat. Because this modem keeps turning up its transmit it sounds like it was trying to overcome some sort of unwanted noise.

Keep an eye on your upstream SNR (signal to noise ratio), if the problem persists let the tech know what its doing in relation to the upstream levels. If it is a noise issue in the plant it's probably affecting many modems and maintenance is probably already aware there is an issue.

You and News are 0% correct. You are going backwards.

What scientific proof do you or News have that temperature changes affects the DL frequencies more than the Upload frequencies?