Here is a list of all the postings Roger Dyke has made in our forums. Click on a thread name to jump to the thread.
|Thread: Understanding the numbers....|
Denis: I fully understand that during the take-off, flight, and landing, there will always be the occasional blind spots shielding the signal. What I am concerned about is how dramatically different the signal strength is between this model and two others I have with exactly the same equipment. Especially as the aircraft in question has much better places within it to position the antennas. It also now has an extra satellite receiver fitted. The expected frame losses for a 10 minute flight are supposed to be about 20 or less which is what I achieve with my other models. With this one I'm getting 286. That's terrible.
brokenenglish: Unless you run a system that has telemetry, you wouldn't be aware of the transmission quality, as you wouldn't see the numbers transmitted back from the receiver. I agree with you. All my models fly with no problem too if I just carry out a range check and ignore the telemetry. I too have never had a single glitch or problem whilst flying. The telemetry just tells me how poor the radio link is to this particular plane and gives me the opportunity of improving it.
Don: I hear what you say and will always bow to the more knowledgeable than I, but wouldn't think it was the engine that was causing the problem. The engine is about 10" from the first two receiver antennas and 20" from the satellite antennas. That's quite a distance. They are also in an un-cluttered area. The antennas in my other IC planes are much, much closer and I don't have any problem with those at all. For starters I'm not going to move the antennas again as I believe they're probably fine. I'm going to change the receiver and then take it one stage at a time. I fly all my planes roughly the same circuits and distances and three out of four of them are fine, so it looks like I have something to find. I will get there...….. Eventually......
Don: It's quite a wide fuselage and quite a long space. The model is an old Dave Smith Super Dalotel with a 68" wingspan and a SC61 2 stroke engine. I am not pushed for room (as I was with the other models with the same receiver). All the four antennas are between 3" and 8" apart and are not close to any large or metal objects. They look like they are ideally placed.
You may well be right. Why I am a bit puzzled is that the other two aircraft fitted with the same receivers show far better results (even without the added satellite receiver).
Mind you, I didn't fly them on the same day as this one.
I have 4 model aircraft. One with a Spektrum AR6600T receiver plus Remote, and three with Orange R620X receivers. All receivers are new.
Two of the three aircraft fitted with R620X receivers are fine returning around from the telemetry 10 - 25 frame losses after about 8 minute flights.
The third aircraft fitted with an R620X is giving me problems. It range checks fine with all the control surfaces moving smoothly. However, the first time I flew it after installing a new receiver a few weeks ago I noticed that the telemetry returns were quite high giving A - 1200, B - 150, F - 120, H - 0. After repositioning the antennas to what I thought were good locations I flew it again. The figures were more or less the same. The aircraft had showed no sign of any glitches. Following repositioning the antennas once more, I also purchased the R110XL satellite receiver which I added to the aircraft and carefully positioned it's antennas quite a distance from any objects or metalwork. I now have 4 antennas all spaced out and pointing in different directions. I then re-bound it all and flew the model again. I had two impeccable flights from the aircraft with no sign of any glitches at all and was quite pleased. Until I looked at the telemetry data. See below.
A - 1326, B - 158, F - 286, H - 0, L - 0, R - 0
The numbers were more or less about the same but included 2 Holds.
What do you reckon? Bad receiver perhaps? I do have a spare one. Worth a try?
Steve and Dennis,
Thanks for your replies. From what I understand from your replies is that an allowance is made for an extra satellite receiver. I suppose that makes sense.
Does anyone know what the 'L' and 'R' is for on the telemetry listing?
On my models there is always a zero in both.
|Thread: DX6 Voice Alert?|
So that's what it is. I couldn't find any explanation for it in the manual.
Thanks once again.
Just another one before I go....
What is a model memory timer and what is it for?
John: Ahhh...... Now sorted. Thank you so much for your help. I'd been going around in circles.
Having recently purchased a Spektrum DX6 TX, I have more or less got to grips with most of it's functions. However I am in a bit of a puzzle in assigning a voice alert to the throttle-cut switch which I have assigned to switch 'A'.
Could any of you more knowledgeable types explain how to do this please?
|Thread: Understanding the numbers....|
Don: You may be right about shadowing, depending on what type of circuits flown, left or right. I'm reasonably happy with the result though.
Update for the Spektrum AR6600T receiver plus remote.
Visited the flying field today to check out the telemetry numbers after fitting the remote receiver. After two flights, the numbers were as follows:-
1st flight (5 mins): A - 279, B - 29, Frames - 2, Holds - 0
2nd flight (8 mins): A - 402, B - 91, Frames - 18, Holds - 0
On the 2nd flight I flew to the extremes of my vision for distance and height.
The figures look okay to me.
Don: I know what you are saying and I'm not adverse to gaining access to different places in the model if I need to. I would just like to explore the options first. I have now fitted the remote receiver in what I think is a favoured place and I will be interested to see the results next time I visit the flying field.
Steve and Don: In aircraft 2 with the Spektrum receiver I did not have the remote receiver fitted as I didn't have much room and it appeared to work okay. I had just finished the model and completed it's covering so didn't really want to start hacking it about. Since returning home and posting the above figures I have managed to find a place to fit the remote receiver. Just by a way of getting some comparison I placed the model 28 paces down my garden and operated the TX on reduced power for a few minutes from the kitchen table. Below are the before and after figures when fitting the remote receiver.
Before: A - 1115, B ------, Frames - 1115, Holds - 0, -46dBm, 100%R
After: A - 1334, B - 151, Frames - 141, Holds - 0, -46dBm, 100%R
I think that the figures are probably now more in keeping with the figures I obtained from Aircraft 1.
Steve: That is correct as there really wasn't room for it in the aircraft and the receiver seemed to be functioning okay without. Is this bad news?
Just for interest for those who would like to know, I managed to get up to my flying field today after a few weeks lay-off due to the HS2 archaeological survey being carried out. I took two of the four of my aircraft recently converted from 35MHz to 2.4GHz. This was the first time that I was able to do an airborne test of the telemetry numbers. They were 4 successful 5 minute flights (2 each) both with an IC engine.
Aircraft 1 - Receiver Orange R620X V2 Aircraft 2 - Receiver Spektrum AR6600T
Aircraft 1 flight 1: A - 256, B - 36, Frames - 25, Holds - 0
Aircraft 1 flight 2: A - 211, B - 9, Frames - 6, Holds - 0
Aircraft 2 flight 1: A - 93, B - 0, Frames - 93, Holds - 0
Aircraft 2 flight 2: A - 113, B - 0, Frames - 113, Holds - 0
The antennas in both aircraft have been placed at 90 degs to each other and in the best places possible given the constraints allowed.
In looking at the telemetry figures whilst doing a range check on reduced power, it was a bit of a joke with the numbers dancing all over the place including picking up a couple of holds. That ignored, the control surfaces seemed to be working fine. Anyway, a good day for me, especially as one of the aircraft was even on it's maiden flight.
brokenenglish: I'm inclined to agree. We tend to get blinded by all the technology with all these wonderful statistics to look at, but the bottom line is are our sticks controlling the aircraft. The old type range check has always stood the test of time for me so maybe that's the way I will continue.
Steve: I do take your point about the telemetry being useful to check whether an antenna is best placed, which does give us the opportunity to move it if necessary.
Steve: Thank you for the info.
Cuban8: Like I mentioned to Don (above), I am in danger of over-thinking this and it is probably a case of too much information. Especially when we can't get a solid answer (even from the manufacturers) as to what it all means as to what is good and what is bad. Thanks for the information.
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