ECN Forum Forums General Topics of the Trade General Discussion Area Cable Television signal testers

Here is my two cents worth. Invest in a good crimper, stripper, and learn how to use them correctly. In addition use quality hardware, connectors, and cable.

Using good tools helps, the connection is not the only concern, cable kinks, and length of cable are usually the problems we find in bad installs, one reason they don't call back may be they were not satified with a failed cable, about half of our repair work is from poor cable installs, in this area if it is interior wiring, the cable company charges for repair work, many times the TV reception was fine, then they signed up for cable modem, or added Digital Sat TV then the problems appeared, as Hal noted, there is more involved then just running a cable, and crimping a few connector on.
We value our customers, and would not think of letting the cable guy fix a problem that can be avoided with good testing, installations may differ, depending on the area and services offered, here multi services are offered on cable, including phone services, one good reason for testing, is they just may be using digital phone service, and a missed 911 call, or they have their security services monitored by cable, it can be a real disaster.



[This message has been edited by LK (edited 11-14-2005).]

When I worked with LP UHF & MMDS transmitters, we would actually use spectrum analyzers with tracking generators to check our cables. Depending on the application, RF power meters and directional couplers too. It can get pretty elaborate and cost prohibitive. I wonder if any folks doing this kind of work might have access to a frequency agile RF modulator? Not out of the question with home theater systems these days. If you do, that and a wide band power meter would give you the means of doing the equiv. of a 3 step(or more) slope test. You would just have to observe the flatness of the output of the modulator according to the meter before inserting the installation cabling into the path. I was looking at some of your posts about the various power meters. What do you do if the signal (cable?) isn't available yet? Do some of these meters also generate a signal that you can inject? Just curious.
Joe

I never found out, but our cable TV provider has some type of signal meter that shows up on our screen near channel 98 or something like that. Does anyone know what that is for, and does it offer any signal description?

"What do you do if the signal (cable?) isn't available yet? Do some of these meters also generate a signal that you can inject? Just curious.
Joe"

What we have is a portable dish on a stand, just takes a few minutes to point, an there is our test signal, it is the digital switches, that present a problem when testing, best to have all the equipment in place, then do your testing, cable on steriods, has presented a real chalange for installers.

Ron,
They ping out a signal for their installers to use for signal level, when they do the install, this is a general test, and a pretty good indication of reception.

[This message has been edited by LK (edited 11-14-2005).]

Ok, now this is getting ridiculous.

Some of you may know that we used to do a lot of work for the cable companies, both outside plant and multiple dwelling units. We usually designed everything we did. Before that I had a large MATV company that did pretty much the same thing with off-air TV and multiple dwelling units like apartment buildings and condos. So I should know what I'm talking about.

To answer your question, no, a signal level meter does not provide it's own signal. You have to be connected to the cable system in order to use it and you also have to have the distribution such as splitters complete but that's not your job so that should end the arguement right there.

But then we have LK who evidently carries a dish and receiver around with him. Trying to figure that one out. I thought we were talking about CATV? Are you in the sat business?

Joe, cable systems have "sweep" systems in place to maintain the system levels. They operate transparently to normal TV reception and use receivers that have a display similar to a spectrum analyzer. The sweep is only used for trunk and feeder adjustment and maintenance, never for non-critical stuff like drops and building distribution. Just not necessary.

We value our customers, and would not think of letting the cable guy fix a problem that can be avoided with good testing, installations may differ, depending on the area and services offered, here multi services are offered on cable, including phone services, one good reason for testing, is they just may be using digital phone service, and a missed 911 call, or they have their security services monitored by cable, it can be a real disaster.

Again, unless you are an experienced CATV or sat system installer and have the knowledge to design and test your work you have no business doing anything other than running cables.

-Hal

AFIAIK, that CH98 thing is a return channel monitor (usually a spectrum analyzer), so a field tech can instantly see the signal going back.

Hal,

The old analog systems are long gone, everyone is going digital, the post was " If you folks do cable televison installations, how do you check if the connection was made correctly?"

With cable service suppliers going digital, they are offering more services today, then just TV, with that said inside cable wiring is more critical then it was in the past days of analog signals.

LK,
You've got me a little confuzzed here. Are you saying that you connect the LNB at a cable entrance and a receiver at the far end? If so, that would verify the DC path for LNB power and polarization, perhaps 25Hz for any switch, and bandpass from 950-1450MHz. It wouldn't verify any of the VHF or cable bands. If you use the RF output of the receiver, you're probably just checking channel 3 or 4.

Hal,
Is the signal level meter that you describe one with a tunable, perhaps 6MHz 3dB BW? I don't think it is unreasonable to want to have a way of testing your work without relying on cable company equipment or personnel. If for no other reason, they might not even be in a new developement while cable is getting roughed in. I would think that companies that manufacture high quality level meters would also produce signal generators that cover the cable spectrum to partner with them.
Joe

Joe,

We ping a broadband transponder, then use our digital receiver, for signal injection, we can also generate just about any signal we need, on the other end is the Leader signal equipment or RF Analyzer, the analyzer is a bit pricy for most, a $2,000 piece of equipment is not for everyone, ours goes from 100khz to 2.06 GHz. very nice display, and plenty of presets.

Spent a lot of time in the communications field, everything from shore stations to ground stations, now i spend lot of time on the low bands, still enjoy the cw chat, but the HF guys are out there doing some wild things these days.

WB2OMS
Les



[This message has been edited by LK (edited 11-15-2005).]