Yeh, sorry, NEIL
It is my understanding (and I'm no expert here) that the 3VCS is Digital, period.
The slower modes, ie PPM, do seem to work fine with
most analogue servos, though I have heard of some servos being fried in this mode (mostly hi-tec). I have used older KO analogue servos with no problem in my cars in the past, using non HRS 40mhz receivers in PPM mode. So your PS713 will
probably be fine.