TDR Pictures from W4ZT
Taken with the Riser Bond 1205C TDR on 10/10/2003 and uploaded to the computer using wave-view. The feedline is an old piece of 1/2 inch heliax which runs from inside the house up to the four 2-meter dipoles near the top of the tower. The return loss measurements (dbrl) don't mean anything with a complex termination on the end of the cable. The velocity factor (VOP - Velocity of Propagation) was adjusted to get the proper length of the RG-58 which was a known length. Note that the VOP is NOT 66% but 59% (this difference is typical and you find the VOP different for many different pieces of coax).

This picture has cursor 1 at the instrument; the first pulse on the left side. Cursor 2 is 25 feet out to the right where the 25 ft piece of RG-58 joins the 1/2 inch heliax. A small "S" bump in the waveform is there.

Here cursor 2 is at the end of the heliax where it joins the matching harness for the 4 dipoles.

Cursor 2 is at one of two unknown bumps in the feedline. This one looks like a connector about half way up the tower. I don't remember a connector in that coax but there could be one there.

Cursor 2 is at the beginning of an elongated disturbance which doesn't look like a connector. I don't know what it is. It may be a bad splice, a bad place caused by lightning, or something else. One day I will have to figure that out.

This is the over-all picture with the gain turned up so you can see the bumps in the feedline clearer.
Links to other TDR shots and information
KN4YZ Skywarn Repeater - 444.675
K4SEX Newnan
ABC's of TDR's - Select the library tab and pick Cable Test, Application Notes. Select the document from the list.