Token Bird,
I dont know if this helps but the way I remeber everything about gyros is:
R - T (1)
E I A (2)
S I X (2)
T - D (2)
I know that looks daft but let me explain.
Down the left hand side you have the word REST, and that stands for R = Rate gyro, E = Earth gyro, S = Space gyro, T = Tied gyro.
Then in the middle column you have a "Bed" (Headboard, mattress and foot board), these are the spin axis of the named gyros ie Rate gyro has a horizontal axis, Earth gyro has a vertical axis.
In the next column is the word taxd (You REST in bed because you are TAXD - cheesy but it works for me!).
The letters represent the instrument these gryos are in.
T = Turn Indicator
A = Artificial horizon
X= nothing exists called x!
D = Direction Indicator
Then the last columns are the degrees of freedom.
I hope that makes sense and is of use to you, it certainly helped me pass my JAR Instruments paper!
All the best
TBL
edited for strange words