This is in danger of getting confusing! I think Oxford Blue pretty much summed things up very well but to summarise the properties of a Lambert's Chart, is has:
1 (and only one) Parallel of Origin, where the convergency on the chart (i.e. the angle with which the meridians of longitude come together as you go North in the Northern Hemisphere) is equal to the Earth's convergency. Elsewhere on the chart this will not be the case.
2 Standard Parallels (either side of the Parallel of Origin, although the P of O is not exactly halfway between) where the scale on the chart is exactly what it says on the tin. This is where the cone used for the projection intersects the reduced Earth. The scale contracts between the standard parallels and expands outside of them.
I'm not aware of any chart that you could get hold of where there is only 1 standard parallel, which would have to be the same as the parallel of origin. I'm willing to be corrected though...
