I have a Tower Hobbies Tower 40 trainer. It comes with a TH Tx with NiCd batteries.

My question is: How often to charge the unit?

With NiCd, I am worried about "memory" so charging after each flight day seems bad (especially if only one flight). But waiting for a loss of power during flight is bad too.

For example, had it out yesturday for only one flight. Will take it out next Saturday. Should I charge again? Wait for x number of flights?

Should the Rx battery in the plane last the same/more/less than Tx (which at least has some lights for warning).

(Note the TH Tx does not have a meter...just red and green lights with a warning flashing at low power).