David Bowman <g0mrf@...>
That looks interesting.... Is it this one you have?
Unfortunately the manual doesn't show any pics of the unit in use.
However, I would have thought that it should show a flat line (low SWR or high return loss) up to just above the band of interest
and then the graph should start to change as the attenuation of the LPF starts to take effect.
Having the 50 load on the end is exactly right.....they all seem to work nicely here, but it is reassuring to see the plot of frequency if you have the kit to measure it.