
Yesterday, after the ‘8:35 on the 805’ QSO in one of our ‘post-QSO QSOs’ I put out a call for help in understanding how I could determine whether or not my cable modem was actually sending a useful internet and tv signal into my home.

I was frustrated that my cable provider’s customer service representative was telling me that he could ‘see’ my modem and it was working fine. He pointed the finger of guilt toward my Wi-Fi router and/or my streaming device.
‘We have no reported outages in your area’ was the final phrase that let me know the CSR had no interest in actually helping me.

If others could ‘look at’ my cable modem and pronounce it as ‘working’ from some distant location, why couldn’t I do the same as I stared at that black box in my own home? I then realized that a good deal of my frustration was not with the cable company or its personnel…it was with my own ignorance of how the darn thing worked.
I wanted to understand that box in the same way I’ve learned to understand my radios. I yearned to put a meter on it and use a tester in some way. I wanted to tune or adjust or solder something.
Neil W2NDG and Jim K2BHM responded to my plea for help and Bob K2LD sent me a link to an article when he heard us communicating over the ‘805’ repeater. The background, tips and link that Neil, Jim and Bob provided led me to the single best technical article I’ve been able to find on this topic.

I feel better now and I know what to do next time the cable service fails…and we all know it will!
Here’s a link I pass on as a ‘Post-Christmas gift’. https://computer.howstuffworks.com/cable-modem.htm.
Happy New Year!
This is a link to the helpful article Bob K2LD provided which led me to the resource cited above:
You may be able to check the status of your modem. Open up a browser and go to 192.168.100.1. You may see this come up.
Spectrum will look at this page to check Status, Signal and Logs. You can see everybody is happy on this Status Page. The Signal page should show you 4 downstream channels with about 40 dB signal to noise and an output of about 4 dB. You will also see 4 upstream channels, probably putting out about 40 dB. At the bottom, it will show you how much data was passed successfully, how much needed correction, and how much was uncorrectable. The last two should be small and insignificant. If you can access this page, it will look similar and give you a good indication that your modem is working. Obviously, spectrum can go further if there is a problem here. All you can do is look and pray!
Thanks Jim! This may be the most helpful bit of all! Happy Day.