Originally Posted by Kambalunga

SPC is not really usefull. Two power supplys but give you no redundance.

1. SPC IS usefull!

2. Redundance was not the aim of the SPC-socket.

The voltage of interest is more the servo voltage.

Why? The servos are working also when the current, the voltage is down for a few milliseconds, no one would notice that. But not the receiver! The IC inside of the rx is registrating any drop in voltage, even for only a few milliseconds, what makes the rx restarting ........ very bad situation.

The use of the SPC-socket directly from the drive battery is an elegant deviation of that problem, nothing more, nothing less. And, as a side-effect, the user will have the voltage of the drive (main) battery on the screen of his radio ..... without any other devices.

Set the low-voltage warning level to the appropriate value for the battery pack and the user will be warned, when the voltage is dropping below this level, this happens first when the trottle is on full power ...... if that is the case, fly at lower speed and prepare for landing. Perfect for safety flights and save of the life of the batteries.

Some servos make a dangerous sliding tackle even at ~3.6V long before your RX brownout.

If one can feel the servos going slower because of voltage dropping so far ........ the ESC is not the right one for this current drawing or the battery is down anyway ...... besides, using the SPC-socket would have shown this problem of low battery voltage or unstability long time before anybody could notice the servos going slower due to voltage dropping.

A good tool is telemetry and logging direct to the SD-card.
That can the DX7S/8/10/18
A far better tool as SPC or low voltage idle.

Logging the voltage dropping into an SD-card can tell you, why your airplane crashed ...... after the accident. Using the SPC-port tells you directly, during flight in realtime, if there is a problem with your battery so that you can land the airplane safely.

Now ...... what is "better"? And, not to forget: Using the SPC-port is free, no extra cost, while using telemetry in connection with a Spektrum radio needs an additional telemetry transmitter inside of the airplane, an extra cabling und so on.


Udo

Originally Posted by udogigahertz

1. SPC IS usefull!

2. Redundance was not the aim of the SPC-socket.


Why? The servos are working also when the current, the voltage is down for a few milliseconds, no one would notice that. But not the receiver! The IC inside of the rx is registrating any drop in voltage, even for only a few milliseconds, what makes the rx restarting ........ very bad situation.

The use of the SPC-socket directly from the drive battery is an elegant deviation of that problem, nothing more, nothing less. And, as a side-effect, the user will have the voltage of the drive (main) battery on the screen of his radio ..... without any other devices.

Set the low-voltage warning level to the appropriate value for the battery pack and the user will be warned, when the voltage is dropping below this level, this happens first when the trottle is on full power ...... if that is the case, fly at lower speed and prepare for landing. Perfect for safety flights and save of the life of the batteries.

If one can feel the servos going slower because of voltage dropping so far ........ the ESC is not the right one for this current drawing or the battery is down anyway ...... besides, using the SPC-socket would have shown this problem of low battery voltage or unstability long time before anybody could notice the servos going slower due to voltage dropping.

Logging the voltage dropping into an SD-card can tell you, why your airplane crashed ...... after the accident. Using the SPC-port tells you directly, during flight in realtime, if there is a problem with your battery so that you can land the airplane safely.

Now ...... what is "better"? And, not to forget: Using the SPC-port is free, no extra cost, while using telemetry in connection with a Spektrum radio needs an additional telemetry transmitter inside of the airplane, an extra cabling und so on.


Udo

Well put. On top of the obvious differences, the DX8 just felt like a toy in comparison, I did not like the feel at all. Also, I can honestly say I have run my RX voltage dangerously low (testing the system on planes I'm not overly concerned with) and have not had one brown out. I don't know if it is the hardware used in the hitec rx vs spektrum or what. Just my 02