RE: HV servos with stock RX??
High voltage servos, digital servos, and electric retracts all represent challenges to the classic receiver installation and power source.
High peak currents and/or higher applied voltage are obviously the culprit.
My personal experience with this sort of thing involved several seemingly unexplained occurrences of temporary control loss,
intermittent retract gear operation, and so forth.
When all was said and done - - -
One digital servo had an odd failure mode, causing excessive (1.5A) current draw when the servo moved in one direction.
A fairly popular 60A ESC with a built-in BEC was found to have poor peak current capability. The BEC was rated for up to six or so servos,
and 2A+ continuous current.
More than one example of a popular 60-120 electric retract was found to have higher peak current draw than rated or anticipated. A more recently received example of the same electric retract has slower operation and reduced current, and seems to meet the listed current specs. Even so, the retract mechanisms can occasionally get out of sync and require an additional cycle or so to re-sync, using a 6V 6A BEC.
As a result, when I plan on using electric retracts, A separate BEC is used to provide power. The positive power lead is disconnected from the receiver connector, the negative lead from the BEC is in common, and the plus lead fed from the BEC. Since my models are electric powered, The BECs are fed from the same Lipo providing power to the motor speed control.
A newer model 90A speed control from Castle (Talon) has a high current BEC built in, and may be able to eliminate the need for a second BEC in my applications.