Re: Back terminated cable?
Jeremy,
Regarding the remark in post 55 about the capacitance of the resistor. I thought in this situation the reason the HF response would roll off would be due to the capacitance of the circuit the series resistor feeds (in this case the coaxial cable and input it feeds and any capacitance to ground from the proximity of the resistor body to ground) and therefore any tiny self capacitance of the series resistor itself would be helpful, and that to help maintain the HF response it would require a small capacitor in parallel with the resistor, especially for larger values of the resistor, much like what is required in x10 scope probes. In those the ratio of the capacitive divider formed for AC voltages of high frequencies roughly matches that of the resistive divider for DC voltages, to try to get the response flat.
Hugo.
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