Throttle Servo location ?
03-08-2007, 11:17 AM
#26
Senior Member
My Feedback: (1)
RE: Throttle Servo location ?
Ed,
You mention frame drop outs with a PCM receiver. I believe it should still be common practice to perform initial, new plane, range tests with a PPM receiver, not with PCM. Unless the drop out count becomes pretty high the PCM receiver will not indicate the interference, via a "lock out", where the PPM will much more readily make it known. That's why the advice given to the newbies is to range check first with a PPM, then later, after you are fully satisfied that all is as it should be, install a PCM receiver. It also helps a lot if the user understands how a PCM receiver works, what it does, and knows how to set the "failsafes".
As far as drop outs in general, unless the operator has some pretty sophisticated test or telemetry equipment at the site they will have no way of seeing just how much of the radio signals are lost or interfered with in flight. Yes, there's some equipment on the market that lets you see how many glitches you had after you land, but it's going to be pretty pricey, not to mention unusual, to see someone at the field that has the telemetry system that let's them continuously monitor the signal strength and drop outs as they are flying. If they did have it they would be too busy "watching the gauges" to fly the plane and would crash anyway.
In the end, the use of good equipment, secure connections, and proper range checks with a PPM receiver will tell you all that you need to know. If you can pull off a range check of 125 feet or more, engine off and engine running without encountering any issues then you're generally good to go. It's easy to find a boogey man in every closet. Somethimes you have to make a decision is the one in your closet as to whether or not the one in your closet is actually a threat.
You mention frame drop outs with a PCM receiver. I believe it should still be common practice to perform initial, new plane, range tests with a PPM receiver, not with PCM. Unless the drop out count becomes pretty high the PCM receiver will not indicate the interference, via a "lock out", where the PPM will much more readily make it known. That's why the advice given to the newbies is to range check first with a PPM, then later, after you are fully satisfied that all is as it should be, install a PCM receiver. It also helps a lot if the user understands how a PCM receiver works, what it does, and knows how to set the "failsafes".
As far as drop outs in general, unless the operator has some pretty sophisticated test or telemetry equipment at the site they will have no way of seeing just how much of the radio signals are lost or interfered with in flight. Yes, there's some equipment on the market that lets you see how many glitches you had after you land, but it's going to be pretty pricey, not to mention unusual, to see someone at the field that has the telemetry system that let's them continuously monitor the signal strength and drop outs as they are flying. If they did have it they would be too busy "watching the gauges" to fly the plane and would crash anyway.
In the end, the use of good equipment, secure connections, and proper range checks with a PPM receiver will tell you all that you need to know. If you can pull off a range check of 125 feet or more, engine off and engine running without encountering any issues then you're generally good to go. It's easy to find a boogey man in every closet. Somethimes you have to make a decision is the one in your closet as to whether or not the one in your closet is actually a threat.
03-08-2007, 01:34 PM
#27
RE: Throttle Servo location ?
There is a ton of great info showing up here. I love it....
In my experience RF does not "go away" because PCM is used, RF will get worse and eventually PCM and the 2.4Ghx stuff will not overcome it.
The PCM issue I have been aware of for a long time but just a few weeks ago I experienced loclout on the DX7. At first I blamed it on the TX because I'm on my 4th one because the screens were going blank and I was loosing control intermittently on more than one plane.
Well one day I was flying my well flown Cap with the DX& and loving life. I had just installed a Brison 3.2 in place of the well run in DA50 so that it could be sent off for service and 2 flights later I was getting intermittent lockouts. At first I thought the TX again but it got worse and worse and I did get the plane back in one piece. I got home all disgusted to find the plug had worked loose because during the install I only made it finger tight, yep my bad. The engine would still run but OH man the RF it was putting out was incredible
My point is given even time, RF will get worse, my example is extreme but is something that can happen. Until I started on the DX7 and even to this day using my 10x on my bigger stuff, I will test fly several flights as well as doing multiple range checks using PPM first. If I get RF (poor range checks) then I find the problem and fix it. 2.4 stuff does a very nice job of filtering as does PCM but it can only do so much.
Never use PCM to compensate for a RF issue, it will bite you
In my experience RF does not "go away" because PCM is used, RF will get worse and eventually PCM and the 2.4Ghx stuff will not overcome it.
The PCM issue I have been aware of for a long time but just a few weeks ago I experienced loclout on the DX7. At first I blamed it on the TX because I'm on my 4th one because the screens were going blank and I was loosing control intermittently on more than one plane.
Well one day I was flying my well flown Cap with the DX& and loving life. I had just installed a Brison 3.2 in place of the well run in DA50 so that it could be sent off for service and 2 flights later I was getting intermittent lockouts. At first I thought the TX again but it got worse and worse and I did get the plane back in one piece. I got home all disgusted to find the plug had worked loose because during the install I only made it finger tight, yep my bad. The engine would still run but OH man the RF it was putting out was incredible
My point is given even time, RF will get worse, my example is extreme but is something that can happen. Until I started on the DX7 and even to this day using my 10x on my bigger stuff, I will test fly several flights as well as doing multiple range checks using PPM first. If I get RF (poor range checks) then I find the problem and fix it. 2.4 stuff does a very nice job of filtering as does PCM but it can only do so much.
Never use PCM to compensate for a RF issue, it will bite you
