range checks
02-07-2005, 08:46 AM
#2
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RE: range checks
Dave,
I am going to piggyback onto your post and add a few questions regarding range checks.
The information I have for the range checks were obtained from the very detailed article on horizons website for PCM range checking which may be found here: [link]http://www.horizonhobby.com/Explore/Article.aspx?ArticleID=1079&Page=1[/link] Here is the blurb from the article regarding the transmitter antennas:
"Collapse or Remove Antenna.
There seems to be a lot of confusion regarding whether one should check range with antennas installed or removed.
Here's the correct method:
JR 10 channel transmitter: Antenna REMOVED
All other JR transmitters: Antenna COLLAPSED
Because of the 10X's unique ball-swivel feature, the transmitter's output without the antenna installed is roughly equal to all other transmitters with their antenna's collapsed.
Worried about hurting the 10X's output? Don't be. It's true that lengthy, continuous operation of a transmitter without the antenna places extra load on the output transistor in the module. Your module will get hot and it is the heat that weakens the transistor. But for short periods - 5 minutes or less, heat build up is minimal and not a factor. "
For the proper distance on range checks (Based on the mentioned article):
Range check distances:
Minimums:
Engine off: 175 feet (60 paces)
Engine running: 150 feet (50 paces)
Hopefully Danny will reconfirm the above infromation???.
Now for my questoins
I am running a JR 955 reciever with 8611 servos throughout a comp-arf 2.6 extra. The elevator servos are run on seperate wires into seperate channels into the reciever. The elevator wires are run parallel to each other back to the servos. I have the elevators programed to go full up on fail safe.
When performing the range check with the antenna removed, the right elevator half acts sluggish and sometimes responds opposite of the left elevator. The left elevator half responds as expected with inputs from the transmitter. Neither elevator goes to full up indicating a lock out of the reciever until well beyond the 175 foot range check. The range check with the engine running was consistent with the engine off.
On the intial flight of the plane, everything was fine but there was one minor glitch in flight that I brushed off as being an abnomally. The second flight was much worse in that it appears that the reciever did lockout very briefly and the plane responded with full elevator up inputs to make an inpressive wall at half throttle. Fortunately it was brief and I was able to land the plane without any issues.
I have subsequently rerouted the two elevator servo wires to have a max seperation and have changed the wires to 18 gage wire vise the high quality JR wires. Range checks with the new wiring configuration showed both elevator halves to behave properly.
My questions are:
Could interference cause the elevator halves to act differently but still not lockout the reciever, similar to what I was seeing with the initial range checks?
Could the above wiring run be the cause of the lockout I observed in flight or there other issues that could be the problem?
One thing I am going to do different is how the elevators are programmed for fail safe, I am going back to fail as in for the flight and full up during the range check. Not sure how many more times the plane will survive a wall at half throttle.
Thanks.
I am going to piggyback onto your post and add a few questions regarding range checks.
The information I have for the range checks were obtained from the very detailed article on horizons website for PCM range checking which may be found here: [link]http://www.horizonhobby.com/Explore/Article.aspx?ArticleID=1079&Page=1[/link] Here is the blurb from the article regarding the transmitter antennas:
"Collapse or Remove Antenna.
There seems to be a lot of confusion regarding whether one should check range with antennas installed or removed.
Here's the correct method:
JR 10 channel transmitter: Antenna REMOVED
All other JR transmitters: Antenna COLLAPSED
Because of the 10X's unique ball-swivel feature, the transmitter's output without the antenna installed is roughly equal to all other transmitters with their antenna's collapsed.
Worried about hurting the 10X's output? Don't be. It's true that lengthy, continuous operation of a transmitter without the antenna places extra load on the output transistor in the module. Your module will get hot and it is the heat that weakens the transistor. But for short periods - 5 minutes or less, heat build up is minimal and not a factor. "
For the proper distance on range checks (Based on the mentioned article):
Range check distances:
Minimums:
Engine off: 175 feet (60 paces)
Engine running: 150 feet (50 paces)
Hopefully Danny will reconfirm the above infromation???.
Now for my questoins
I am running a JR 955 reciever with 8611 servos throughout a comp-arf 2.6 extra. The elevator servos are run on seperate wires into seperate channels into the reciever. The elevator wires are run parallel to each other back to the servos. I have the elevators programed to go full up on fail safe.
When performing the range check with the antenna removed, the right elevator half acts sluggish and sometimes responds opposite of the left elevator. The left elevator half responds as expected with inputs from the transmitter. Neither elevator goes to full up indicating a lock out of the reciever until well beyond the 175 foot range check. The range check with the engine running was consistent with the engine off.
On the intial flight of the plane, everything was fine but there was one minor glitch in flight that I brushed off as being an abnomally. The second flight was much worse in that it appears that the reciever did lockout very briefly and the plane responded with full elevator up inputs to make an inpressive wall at half throttle. Fortunately it was brief and I was able to land the plane without any issues.
I have subsequently rerouted the two elevator servo wires to have a max seperation and have changed the wires to 18 gage wire vise the high quality JR wires. Range checks with the new wiring configuration showed both elevator halves to behave properly.
My questions are:
Could interference cause the elevator halves to act differently but still not lockout the reciever, similar to what I was seeing with the initial range checks?
Could the above wiring run be the cause of the lockout I observed in flight or there other issues that could be the problem?
One thing I am going to do different is how the elevators are programmed for fail safe, I am going back to fail as in for the flight and full up during the range check. Not sure how many more times the plane will survive a wall at half throttle.
Thanks.
02-07-2005, 10:59 AM
#3
RE: range checks
That information is correct.
Yes, it is possible that one channel can be affected by a hit prior to other channels, and if the noise causing the problem ceases fast enough it can only affect one channel. Wiring can cause issues from time to time, things like dirty connetors, or pin size differences with aftermarket extensions, or just the way they are routed can cause problems. If that is the extent of the issues you encountered, is difficult to say without complete range testing.
Yes, it is possible that one channel can be affected by a hit prior to other channels, and if the noise causing the problem ceases fast enough it can only affect one channel. Wiring can cause issues from time to time, things like dirty connetors, or pin size differences with aftermarket extensions, or just the way they are routed can cause problems. If that is the extent of the issues you encountered, is difficult to say without complete range testing.
