I have a Power expander Pro that I will be using with the New Hitec Optima 9 receiver....

My question is does the "receiver connection advisory" apply to the Hitec 2.4 series receivers also? I would like to power the SPC port with one connection and the Batt/CH9 port with another connection from the two receiver power leads on the expander board.

I'm planning to feed the Expander board with 2x 2100mah lipo's Un-regulated (My servos and the receiver handle the voltage)

Thanks for any help.

Hi,
The two receiver leads that come off the Pro that have 3 wires are both power AND the first and last channel. They should be plugged into servo outputs on the receiver and you can still use those servo outputs as channels A and J. There is not reason to plug these into the battery ports on the receiver, plugging them into servo ports does not cost you any unusable channels. Please let me know if you need more explanation.

AH HA, Guess if I would have read the instructions a little better I would have seen that. Its right there in the manual

Thanks for the reply!!

I am using PE original with Optima 9. From the Udean out, it goes to SPC port so I can see the actual battery voltage not the 5v regulated that feeds into the receiver.

I wondered about doing something similar although I dont think its mandatory. Got the system up and running and its working great!!

IMHO, DO NOT go through the SPC port. You'll see on the power expander that the 1st and last channel is the powered one. That way, you have two input to the receiver (in case one of them ever goes out... not that it would ).

I have the 10EQ on my Optima 9, and in essence, I just don't use the 9th channel on the power expander, and instead plug Optima's channel 9 to the 10th channel.

IMHO, DO NOT go through the SPC port.

It is not used as a backup power but only to monitor the receiver lipo voltage in reatime. Even though the system is unregulated, the receiver only sees 5v due to the way PE powers the receiver. If I did not use the PE, I would just power two channels with Y cable and not bother with the SPC since servo voltage = lipo voltage in this case.

Originally Posted by BoneDoc

IMHO, DO NOT go through the SPC port. You'll see on the power expander that the 1st and last channel is the powered one. That way, you have two input to the receiver (in case one of them ever goes out... not that it would ).

I have the 10EQ on my Optima 9, and in essence, I just don't use the 9th channel on the power expander, and instead plug Optima's channel 9 to the 10th channel.

Yep, thats pretty much how I did it. Powered ports from the PE board are in receiver channels 1 and 8. used channel 9 on the receiver with one of the middle single wires.

The problem with the SPC is that if you loose connection with it, that's it. Granted the chance is really rare, but I'd feel a tad better with two input into the receiver.

Originally Posted by red_z06

I am using PE original with Optima 9. From the Udean out, it goes to SPC port so I can see the actual battery voltage not the 5v regulated that feeds into the receiver.

Hi,
I am not sure how the receiver works but if you are feeding more than 5V into the receiver from the Deans output and that gets to the other servo channels' power and ground you could blow the buffers on the PowerExpander. PLEASE BE VERY CAREFUL DOING SOMETHING LIKE THIS.

From what I understand if you remove the SPC plug you can power it up to 35volts and it wont send any power to the servos only the signal gets transferred. You will still have to feed the channels traditionally through the servo lead side.

The SPC port is intended to be powered by a stand alone flight pack such as a 2s lipo or more but leaving the plug installed it gets its voltage form the servo feed side.

I hope I explained that right....

I'm leaving mine as is, it works great!!

Hitec receiver has two isolated bus. One for the servos and one for receiver only. The receiver only can handle upto 35v input and servos will not see this.

Originally Posted by rrritchey

Hi,
I am not sure how the receiver works but if you are feeding more than 5V into the receiver from the Deans output and that gets to the other servo channels' power and ground you could blow the buffers on the PowerExpander. PLEASE BE VERY CAREFUL DOING SOMETHING LIKE THIS.

Originally Posted by red_z06

Hitec receiver has two isolated bus. One for the servos and one for receiver only. The receiver only can handle upto 35v input and servos will not see this.

OK, I learn something every day. Thanks for clearing this up.

I have a question for the officianado's. Is it necessary to mount the antennas on the Optima 9 90 degrees of each other. I had an airplane go in where the controls froze. The model had been flown about 20 times. I was running 4 cell nicad pack. Voltage on take off read 5.1 on the receiver. I flew the plane for about 10 minutes and took it up between 200-300 feet. I started to put it in a flat spin and the plane locked at full throttle heading straigt down. You all know the rest of the story. I did have the reciever antennas mounted on each side of the fuse. They were mounted identically on each side but in the same orienation. I am okay that this was a .60 sized sport plane that I used to test receivers lost at minimal expense. However, I have several giant scale warbirds and a brand new 37% Ultimate. I purchased 8 of these recievers for various airplanes that I have. I needed to find out if the antenna orientation was the potential reason for the lock out. The post mortem review showed 5.0 volts on the battery. BTW range check worked perfect as always pre flight. i could not find anything in the manual talking about antenna orientation. I know that this is recommended on Futaba receivers. Thanks
John

Sorry to hear about your loss.

Jim