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The point of this thread is to show the sort of currents that can be drawn by powerful servos for very short periods so that if you are using 4 cell batteries that will suffer voltage drop such as high capacity AA nimhs you can't be complacent because your ammeter showed an average 0.1 amps for example over 1 second.
I doubt anyone would use a 4 cell AA NiMH with high power servos
What would you consider a valid time frame for this type of measurement?
.......I have no idea, I was hoping someone knowledgable would jump in with info on how quickly a battery can drop its power, such as there must be a delay or it is simultaneous with the current. .....
So if I am reading this correctly the best fix of all is to feed the RX and servos from separate power sources, so that the receiver always sees a good voltage .
So if I am reading this correctly the best fix of all is to feed the RX and servos from separate power sources, so that the receiver always sees a good voltage .Simon
Another way is to carry just 2 batteries but of sufficient capacity and pass each through a diode, they have to be 5 cell batteries to compensate for the diode's small voltage loss, this way you get two battery redundancy, probability of a diode failure incredibly low, and the greater starting voltage means it is very unlikely that a battery will be dragged down to the rx switch off voltage.
Tom, decent quality nicads or nimh batteries actually fail incredibly rarely during use. Problems in mechanical items such as loose wires in switches are at least as likely, maybe more likely, (I once had a switch from a well known brand that seemed a bit intermittent, I opened it up and found the wire had not actually been soldered onto the tag) and if these float about and cause a short then you do need the diode to protect the other battery.So the website is correct in that a diode is not needed to protect against battery failure, but it neglects the other components in the system.
Simon with that sort of size of model I would be looking at a power management system such as by Emcotec or Powerbox, both make a redundant receiver system, a device which you plug two rx into and which provides stabilised power etc.
I think we get a bit carried away with some of the gear we fit.