Originally Posted by AndyKunz

Gary,

Don't look at Frames and Holds to find brownout data! That's like asking your altimeter to tell you how fast you're going. If you want to know about power problems, look at the voltage data instead.

If your power problem is so severe that it kills the telemetry, there's not much anybody can do. That's a blackout, not a brownout! It takes power to transmit telemetry, and it is being sent at the same time that your servos are being updated. You need to have adequate power there for that to happen. It doesn't have to be perfect, but it has to be reasonable.

OTOH, the fact that the numbers are reset to 0 (after being non-zero) while in flight IS telling you that you have a power problem because your receiver is being reset.

The fact that the power glitch is so bad that you aren't getting telemetry data when you try to move the servos is telling you there's a HUGE power problem. If you can change it from huge to manageable, then you can start to use the telemetry to help you debug the problems.

If you suspect that there really is a big power problem (it sounds like there is), then you might try powering the telemetry separately and see what happens. You'll need to make some special cables to do that, but you can measure what's happening on the servo bus during those problem times if you use the "flight pack" input to monitor the receiver.

I don't know your skill level. Can you figure out how to do that wiring yourself? Or do you need one of us to draw it out for you?

I'm heading to bed now. I'll check back in the morning. If you need me to draw it out I'd be happy to do that.

Andy

Well, I returned the servos that were causing the problem, so I think I'll be good. I guess I misunderstood the problems the telemetry system monitors.
I thought holds were where the rx looses link the with tx, and that the telemetry would tell me that. I also thought the some of the data (such as min/max) send to and received by the dx8 would remain regardless of the power to the rx/tm1000.

The part that really got me all confused was that I never saw a voltage below 5.9, and then the whole thing would loose link and or reboot. The BEC was a known good one, with probably over 50 successful flights in a previous airplane.
Oh well... servos are gone.

Thanks for explaining things to me Andy. Its nice to have Spektrum guys out and about assisting the end user.

-Gary

You're most welcome.

A "fade" (A, B, R, L) is when a single antenna misses a communication from the transmitter.

A Frame loss (F) is when all antennas miss the same communication from the transmitter.

A Hold (H) is when the receiver is waiting for the tx to say something and doesn't hear anything for 1 full second (45 consecutive frame losses).

All those things require the rx to have power - it's waiting and listening for the transmitter. When the power is interrupted, they are all reset to 0.

Andy

Originally Posted by AndyKunz

You're most welcome.

A "fade" (A, B, R, L) is when a single antenna misses a communication from the transmitter.

A Frame loss (F) is when all antennas miss the same communication from the transmitter.

A Hold (H) is when the receiver is waiting for the tx to say something and doesn't hear anything for 1 full second (45 consecutive frame losses).

All those things require the rx to have power - it's waiting and listening for the transmitter. When the power is interrupted, they are all reset to 0.

Andy

Got it...

Now for the next iteration, you guys need to get with General Atomics... they've got the telemetry thing nailed down! But then again, my tx and rx are much bigger!

Thanks again!

-Gary

I would still be cautious of that BEC. When you get the new servos installed you need to load test the bec. Put pressure on the control surfaces and work the sticks or just hold pressure on all control for a few minutes. Watch the voltage output with the telemetry or a known good voltmeter. Its possible your bec is not strong enough and could reset in flight under a load.

Originally Posted by dfrazier

I would still be cautious of that BEC. When you get the new servos installed you need to load test the bec. Put pressure on the control surfaces and work the sticks or just hold pressure on all control for a few minutes. Watch the voltage output with the telemetry or a known good voltmeter. Its possible your bec is not strong enough and could reset in flight under a load.

I'll keep that in mind, however I tested it with two known functional BECs. They are 3a 5/6v selectable, so I'm sure the cheap servos were just overamping the BEC.