saidj...@aol.com said: > Your plots don't show the wave being reflected by the cable end, and > bouncing back and forth.. Until settling down.
Yes. I'll put up some nasty pictures if anybody wants an ugly example. For that set of graphs, I tried to get rid of that sort of junk. I was working on the bench, using connectors and clipleads rather than PCBs or soldering whatever so things could be (much?) cleaner. For the coax, there was a short chunk of coax from the TBolt to a Tee at the scope, then the long chunk of coax under test, then a 50 ohm terminator at the other scope input. You can see some ringing due to the coax not really matching the terminator. For the twisted pairs, I used clipleads. The first/simple try wasn't good enough. The non-twisted cliplead wires were long enough to cause visible cruft. I ended up with a BNC to cliplead adapter with wires that were only 6 inches long. At the far end, I had a resistor merged into the clipleads, and adjusted it for best results. For the Cat-5 and Cat-6, I used a pair of RJ-45 to DB-9 adapters without the DB-9 connector. The wires coming out of the adapers are about 2 inches long. I forget what I did for the RG-6 which is 75 ohms. I have a pair of 50-75 adapters, but I don't remember doing any scaling to get the graphs to come out right and I don't see anything in the gnuplot commands to make the graphs. So I probably use a cliplead setup like for the twisted pairs. -- These are my opinions. I hate spam. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
