ve3cga

Hi all, I've just got my ultimate bipe flying again after a summer break.
Some time I must have enabled telemetry and while flying earlier in the week my TX started beeping wildly and the lady in the box was muttering something
Turns out I was getting some framing errors and some holds.
Today I went out with it and another plane, nothing on the other plane but the Ultimate again telling me framing errors and holds.
After landing I did a re-bind but it was getting them with the plane not running with the radio on. Did a range check, the enabled the battery telemetry and battery was fine as was the range check
I switched to DSMX from DSM2 and the framing & hold errors were not as frequent. I kept the framing rate at 22ms since I run only analog servos
Shook the plane and checked all connections but nothing obvious.

I checked my other plane TX settings and none of them with the same type AR620 have errors for frame & hold set to anything other than zero

Does zero in the error programming in telemetry mean that error is shut off?

Going to try another AR620 but it seems strange to me and its quite possible I programmed the set point for errors too low but that was back in the spring

what Is a resonable setting for the error trip point for alarms, is 6 too low, there is no noticeable tic or noticeable change in control while getting these errors every few minutes while flying

thanks, Bob

AndyKunz

I'm not sure what screen you're talking about setting things to 0 in. But for telemetry, what turns off alarms is the column on the right where you can select the alarm method - Inhibit, Tone, Vibe, Voice (depending on your radio's hardware capabilities).

Dropped frames is generally not an issue. I published a spreadsheet on RCG explaining how to utilize this information in a very rough way. The best way is to use the telemetry logging feature in your radio so you can review it afterwards on a PC.

An AR620, because the antenna is internal to the receiver, is very particular about how it is installed in the aircraft. What Ultimate are you using?

Holds are an issue if they occur during flight. If you are fiddling with things on the ground, then they're not an issue - they're expected. More information (telemetry log file, again) is needed. You absolutely would notice a hold in flight.

Andy

ve3cga

thanks for getting back to me on this..
I was looking on other forums and here and I now understand positioning the rcvr is important
I was getting odd holds and frame errors while the plane was not running with the transmitter sitting a coule feet away
THe frame and some holds happened while flying
I flew from where I was over the field and landed without any off spurious plane movement, in fact I was wondering what all the fuss was about

I'll get the log from the transmitter and have a look, but I'll also put the receiver in another spot.
Currently it sits over the aluminium landing gear on top of the battery
I'll change that so its behind the tank further back from the front of the plane or possibly in the cockpit

The ultimate is a scaled down size from the carl goldberg print, I think it had a 5 or 6' wing.
Mine is 40" wing and was entirely scratch built from bit & pieces from a tub of small balsa pieces
I wish I built it larger now because after the first test flite a fellow at the club gave me an OS 55ax
Slightly over powered, still coasts in nicely
I've had many dead sticks due to the tank foaming from vibration
The cockpit windscreen is from a 2 liter pop bottle that was heat shrunk over a mold to fit the plane
The landing gear is forward some but with it this way when it lands its down and stays down

AndyKunz

Nice model!
The AR620 is the wrong receiver for that size plane, and you have it in a very bad location. And it absolutely needs to be relocated at least 6" from battery, gear, fuel tank, and engine.
You should be using a receiver with multiple antennas, such as the AR6610T or AR637T. Antennas for these need to be 6" away as well.
Andy

ve3cga

thanks Andy...
I'm going to see what spare receivers I have
still cant figure out why I was getting holds and no odd control behaviors, lucky I guess
I think I must have repositioned the receiver from the back of the tank at some time, never had issues before flying with the radio
I do have some of the older 6ch with dual antennas, they should be better than having a pcb antenna with an rf amp stage amplifying noise etc

Just checked my j3 cub and to my suprise its a 620 as well.. Now that plane does get flown pretty far out being a 6' wing
Havent had problems with that one yet and the 620 is at the back wall of the cockpit, nothing closer than 12"
One thing I'm going to do is have a look on the flight logs on my receivers and just see whats going on.
I use satellite receivers with a 8010 on my extra300 and b25. both are (scratchbuild) 6' wings
Maybe I should build a cheap foam board plane and test the smaller receivers out in it just for interest sake

AndyKunz

With these receivers, placement is critical. That's probably why your J3 works so well and the Ultimate doesn't.

Enable the telemetry logging in your transmitter. It's better for analysis later.

Andy

ve3cga

will do thanks, Bob