Aloft Forums
Welcome to Aloft Forums. Register a free account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!
What receiver should I use?
- Thread starter Laury415
- Start date
Konrad
Very Strong User
This is driving me nuts.
I see that the S-Port (Smart Port) power pins are not soldered to the same power bus (PCB) as the PWM and S-Bus (Serial Bus) power pins. I don't see any heavy power traces coming from the power bus (PCB) onto the RX board. I also noticed than the neg pin on my S-Port is not soldered on this side of the pad. It is well soldered on the back side pad. I also see that the pin PCB has been inspected for solder bridges (blue marker)
I wish there was more technical data available from the OEMs. I miss the days of when the American RC manufactures would give you their drawing if you asked. (Ok I often had to given them my FCC license number to show that I knew what I was trying to do). I think FrSky like much of the rest of the world is having problems with intellectual theft. So I'm sure we will never get detailed drawings of the PCB layout.
I'd still like to learn what is the power output limit for S-Port. And can this even be used as a place to install the power source (power in). If used as a place to hook up the battery is there a blocking diode than might be damaged with power coming into the port verses power going out? I don't think there is a problem with a diode, but I don't know.
All the best,
Konrad
I see that the S-Port (Smart Port) power pins are not soldered to the same power bus (PCB) as the PWM and S-Bus (Serial Bus) power pins. I don't see any heavy power traces coming from the power bus (PCB) onto the RX board. I also noticed than the neg pin on my S-Port is not soldered on this side of the pad. It is well soldered on the back side pad. I also see that the pin PCB has been inspected for solder bridges (blue marker)
I wish there was more technical data available from the OEMs. I miss the days of when the American RC manufactures would give you their drawing if you asked. (Ok I often had to given them my FCC license number to show that I knew what I was trying to do). I think FrSky like much of the rest of the world is having problems with intellectual theft. So I'm sure we will never get detailed drawings of the PCB layout.
I'd still like to learn what is the power output limit for S-Port. And can this even be used as a place to install the power source (power in). If used as a place to hook up the battery is there a blocking diode than might be damaged with power coming into the port verses power going out? I don't think there is a problem with a diode, but I don't know.
All the best,
Konrad
Last edited:
Wow you put way more thought into this than I did. I do appreciate that you open up your receiver to investigate. Yes, I assumed that the Smart port would have had it's power (+ & -) go to a bus in the receiver connecting all power so I am surprised at this. Looks like I won't be able to test power on a PWM till tomorrow morning but I'll post as soon as I do
I was able to test out the rx8r pro receiver with the alternate power connection. I actually used Channel 1 which is my throttle, but instead of using a Y connector I just disconnected the throttle as it wasn't in play during any of my testing. Unfortunately I got the same result. I was able to get the receiver to lock up/brown out almost instantly. To confirm results I reinstalled the original xr8 receiver, again no issues, no brown outs. I'm not sure why the pro receiver is so sensitive to this but obviously it's not usable with this plane and/or these high torque servos. At least my original xr8 receiver works.
I'm wondering if I would still benefit from using a power module (rb10, or rb20) with the xr8 receiver and XM+ receiver. Would that act as a redundant receiver similar to the rx8r pro? I still need 9 channels so not sure if I would still use the Sbus converter, or where the 9th channel comes from?
I'm wondering if I would still benefit from using a power module (rb10, or rb20) with the xr8 receiver and XM+ receiver. Would that act as a redundant receiver similar to the rx8r pro? I still need 9 channels so not sure if I would still use the Sbus converter, or where the 9th channel comes from?
As a side note, I saw this message on Hobbytown's website regarding Savox servos.
"*NOTE: Certain combinations of receiver and ESC have been found to cause "Brown Out" issues when combined with Savox servos. An external BEC, or BEC stabilizing receiver capacitor may be needed for efficient, glitch free operation in low voltage electric applications"
This was not on Savox's website, and I did try setting this up with an external BEC with the same results.
"*NOTE: Certain combinations of receiver and ESC have been found to cause "Brown Out" issues when combined with Savox servos. An external BEC, or BEC stabilizing receiver capacitor may be needed for efficient, glitch free operation in low voltage electric applications"
This was not on Savox's website, and I did try setting this up with an external BEC with the same results.
Konrad
Very Strong User
Sorry I don't have any RB10 or RB20 to test with. Have you tried some other servos as a load. Then keep adding servos until the problem shows up (vary the load) to test if the problem is load related. If the system works well with only a few servos but dies with a full bank of servos then It is in all likelihood a power supply issue.
I've had little or no luck with Glitch Busters, receiver caps, or power filters to condition input power unless they are huge.
I've had little or no luck with Glitch Busters, receiver caps, or power filters to condition input power unless they are huge.
Interesting - I have not heard of anyone being able to brownout a FrSky receiver. This is very odd. As an example, I was building a new plane this weekend and was using an old NiMH battery pack to power my receiver. After a while of this I started to get telemetry lost, telemetry found warnings from my radio, I wiggled my sticks and had no servos, but the receiver was just at the voltage where it was starting to drop out. My point is that FrSky receivers will typically still be working even after voltage has dropped so low that the servos no longer function.
I recall some testing a few years back that showed they were reliable at 2.5 volts. give or take.. I have not tested the newer range of receivers.
So, what is causing these brownouts? You for sure do not want to power via the Smart port. In general with any receiver, if the port you are going to use for power is away from the servo ports, you should avoid it. Some of the FrSky Sbus ports are like this, they are on the opposite end of the receiver, those units are not going to be able to handle a lot of amps, power management needs to be addressed. My general rule is that Sbus setups that are driving servos should always have the power management addressed.
I'm curious why they had that comment about the Savox servos on their site. Might be worth emailing them for some details. I can't think of a reason why the servo would be a problem, but I honestly do not have much experience with that brand.
Why the same setup would work fine with an X8R is very odd, that does suggest something very odd is going on. If you bought this receiver from us, please feel free to send it back. We are currently out of stock on them, so a refund may be best for you.
I recall some testing a few years back that showed they were reliable at 2.5 volts. give or take.. I have not tested the newer range of receivers.
So, what is causing these brownouts? You for sure do not want to power via the Smart port. In general with any receiver, if the port you are going to use for power is away from the servo ports, you should avoid it. Some of the FrSky Sbus ports are like this, they are on the opposite end of the receiver, those units are not going to be able to handle a lot of amps, power management needs to be addressed. My general rule is that Sbus setups that are driving servos should always have the power management addressed.
I'm curious why they had that comment about the Savox servos on their site. Might be worth emailing them for some details. I can't think of a reason why the servo would be a problem, but I honestly do not have much experience with that brand.
Why the same setup would work fine with an X8R is very odd, that does suggest something very odd is going on. If you bought this receiver from us, please feel free to send it back. We are currently out of stock on them, so a refund may be best for you.
Wayne,
Thanks for your reply. Yes I did buy the receiver from Aloft.
I live in Modesto so I'm less then 2 hours from your store. I'm thinking of coming by possibly next week. I would bring the plane and have you or your team take a look and see if there is anything I missed. At that time we can review if I should get a refund or not. Tuesday or Friday next week might work, but I'll call before I come out.
Thanks for your reply. Yes I did buy the receiver from Aloft.
I live in Modesto so I'm less then 2 hours from your store. I'm thinking of coming by possibly next week. I would bring the plane and have you or your team take a look and see if there is anything I missed. At that time we can review if I should get a refund or not. Tuesday or Friday next week might work, but I'll call before I come out.
Sounds perfect - will be interesting to see what may be going on. Try and avoid lunch hour and all should be good. 
Sometimes on Fridays we enjoy a little longer meal as a little extra break after the long week. My guys work their butts off all week long, so I like to do this most weeks.
Sometimes on Fridays we enjoy a little longer meal as a little extra break after the long week. My guys work their butts off all week long, so I like to do this most weeks.
Konrad
Very Strong User
Agree about the guys. They are very helpfull! ?Sounds perfect - will be interesting to see what may be going on. Try and avoid lunch hour and all should be good.
What is your lunch hour?
Similar threads
