Variation of Obital Angular Momentum With Radius

A satellite in orbit about a massive body (or a charged particle orbiting another) decreases in speed as the radius increases - increasing
$r$
means decreasing
$v$

Does the orbital angular momentum increase or decrease?
The magnitude of the orbital angular momentum of a satellite is a circular orbit is
$L=mvr$

Equating the centripetal and gravitational forces gives
$\frac{mv^2}{r} = \frac{GMm}{r^2}$

Rearranging for
$v$
:
$v = \sqrt{\frac{GM}{r}}$

Hence
$L=m \sqrt{\frac{GM}{r}} r = m \sqrt{GMr}$

Increasing
$r$
means increasing
$L$
.