Reflection with decay
Submitted by ben on Fri, 11/05/2010 - 23:44
A fast step is applied to one end of an RG-58 cable (channel 1). The other end (channel 2) is open, causing the signal to reflect back to the transmitter. The transmitter consists of a pullup resistor and a fast relay which shorts the line. There is a short cable connecting the transmitter to the RG-58 between the two oscilloscope channel so there is a brief delay between the reflected signal reaching channel 1 and another reflection coming from the shorted relay contacts.
The exponential decay caused by losses in the cable is clearly visible here.
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