Q: I recently connected my first IP panel to a broadband cable connection. Everything appeared fine and now the customer called and says the line appears dead and the cable provider says they cannot talk to the IP connection. The incoming signal light on the cable modem stays out. However, when I disconnect the cable video feed the IP connection and the customer’s computer works and the cable light is flashing. When I connect the cable video back up the video works but has really bad picture quality. But the high speed data connection does not work. Any ideas?
A: Well the first place to look would be the splitter that branches off your high-speed computer and panel connection from the TV feed. It may be bad. Remember from our earlier discussions on digital signals that you can have a marginal signal working and then all of a sudden it drops off. In this case the weak video is an indicator. Possible the cable run into the house is bad. Normally you would need a dB meter to test this connection; however I have noticed more of the newer routers and cable modems can be access via your computer and give you both an input and output signal strength reading. A pretty cool feature that might come in handy some time.
Q: I recently had some trouble with connecting some video in an elevator car. Instead of using coax I decided to try the noise canceling quality of twisted cable. The elevator car technicians had some shielded twisted pair (STP) available in their control cables. However, when connected up, I was disappointed with the signal even though it was balanced twisted cable and shielded as well.
A: In this case don’t be fooled by the extra shielding on the twisted pair cabling. Some twisted pair transmitter/receiver vendors insist on the cable to be Unshielded Twisted Pair and not STP. The STP can diminish the performance considerably. Double check with the vendor, it can make a big difference.