Len Todd

This is a nice lightweight way to address a switch. I am just not sure I am into a switch though. I typically avoid mechanical switches like the plague. But, ... I'll think about it.

Whatever I end up doing, a tiny Normally Open Push Button switch seems like a good idea. Thanks for the response!

Corsair2013

My Feedback: (2)

Sweet - thanks Andy - I will put a "Y" in my planes tonight and run some test.

Keith

ajay1

Andy, I have a DX18QQ and have updated the version 1.04 on this----I have assigned the Throttle Trim to the Left Lever--The amount of servo travel volume I get by operating this Lever is not sufficient.How can I increase the Servo Travel Volume as I understand that the 1.04 version update makes this possible.

AndyKunz

You should have a full 29+ trim available on the lever. This makes it so it now has the same range as the digital trims.

If you want more trim than than, you have to go to a mix from LLV > THR. Note that the excess will be in all throttle positions, as it is a mix of the "raw device" not the "trim-mode" amount (which varies according to throttle position).

Andy

ajay1

I am using the Spektrum DX18QQ Tx with the PowerBox Royal SRS connected to 4 Spektrum satellites[Carbon Fuselage type} located in the optimum positions of my 3 mts size Sukhoi/Extra models powered by 200 cc Gas engines.
Since years I have been writing/logging the Fades/Frame Loss/Hold of each satellite.In the 4 models I fly my Fades have NEVER exceeded 50 with NIL Frame Loss and NIL Holds.
All of a sudden this weekend my Fades are showing between 500 to 1400 with NIL Frame Loss and NIL Holds.
This has happened on all my 4 models---
The Secluded Flying Field is the same with just 2 other flyers flying on Futaba radios.No change in any other variable.
Is there any Frequeny Counter or RF Spectrum Analyser one should use to check out the environment---Any safeguards
anyone can recomend.
Can my Tx Module have lost power--If so will only the Fades increase allowing Frame Loss and Holds to remain at NIL.


http://www.micro.arocholl.com/

czorzella

I'm certain that Andy will chime in here a little bit later, but lets see if I can help you with this.

There is one flying field in my area where all of a sudden, people started to loose their airplanes; I remember once when three planes went down to the ground at same time; further analysis showed that the issue turned out to be related to strong RF interference making the 2.4gHz band unusable. Remember that those are very rare, very extreme cases, but they indicate that it is possible. There is no jam-proof RF.

This is what I would do:

1) Assuming that you have a telemetry log, you should read it to identify electric issues using a software like this at www.robo-software.com. Check the battery and/or the voltage regulator condition.

2) Do a range test and test your model in different locations at your flying field. It would have been better if you had done a range test when higher rates of frame losses was perceived so that you could compare results. This may indicate environment related issues in case that you have inconsistent results in different locations or maybe that the radio or the receiver must be serviced.

3) You could also crosscheck your telemetry readings with the ones gathered by other pilots at your flying field; If they haven't telemetry, you could use a device like this one to gather such information: Spektrum Flight Log SPM9540 http://www.spektrumrc.com/Products/D...ProdID=SPM9540

Please keep us posted about your findings. Good luck!

Carlos

AndyKunz

Good answer, Carlos.

Ajay, just because a field is remote does not mean that the field is not in a high-RF area. Microwave communications towers are still going in worldwide. They like to transmit above rural areas as you describe because the impact on human activity is minimal. They like the rural areas for the same reason modelers do!

Take your meter out to the field and check. And check at altitude, too, if you can.

You can your friends can check your transmitters on the ground to see that they are within a few dB of one another.

Andy

Corsair2013

My Feedback: (2)

Carlos, I fly in probably one of the most remote spots in the country - North of Grantsville, Utah near Interstate 80 and the great salt lake. Guys have flown there for 20 years but with the change in the weather the ground there can be muddy or even under water some years. Most guys don't come out there anymore but the past few years I have been flying there. I have lost 3 airplanes there and thought it was just me being new to the sport. Recently I was flying my L4 Grasshopper and was high enough and close enough to see and hear the engine cut then come back on. I flew the plane through this same area, higher this time, and had the same reaction. I purchased a Spektrum Data Logger and flew around and found that the microwave tower south east of the field - 1/4 mile was the issue. It is not all the time but sometimes it sends signals right across the flying field and this has caused lots of issues - 3 crashes for myself. Now that I have the area tested I know where to fly and the area to say away from. It is too bad as the microwave shoots right across our normal approach path and our turn onto final.

I wish someone made an inexpensive frequency recording/testing device that would let us map the whole area for all the different frequencies. I know they are out there but am sure they are very expensive.

Keith

Len Todd

Looking at the 2.4 ghz spectrum is a bit difficult because most RF monitors do not go that high in frequency. To do that you are talking a commercial monitor.

I would first do a range check to see if the transmitter is up to snuff. If there was any question at all, it would go back in for service.

Given that it happened to 4 planes, I would typically first suspect the transmitter. Seems to me if there was enough RF interference to cause a significant increase in Fades that eventually a frame loss or two would show up. It sounds like the transmitter output may have dropped a bit, especially if you are seeing an increase in fades on all 4 Rxers.

Corsair2013

My Feedback: (2)

I have a new DX 18 so I will take the planes out when the field is dry and see what I find. The thing is the 3 crashes were 1 with a DX 8 and the other with JR 11x and all different Rx's. I think it is just a bad area at certain times of the day.

Keith

ajay1

Changed to a NEW DX18 Transmitter and the Fades are back to below 50 from the earlier 500 to 1400 Fades with my DX18QQ. Everything else unchanged. I assume the strength of the Rf Output of my DX18QQ has reduced in the 15 months of use.
Just to be double sure flew a short 4 minute flight with my DX18QQ on the same day minutes apart and the fades were back to between 500 to 1400.
I have just ordered a Rf Spectrum Analyser --- http://www.rcgroups.com/forums/showthread.php?t=1402665 .
What is the signal strength one should look for when measuring the Rf Output of a NEW DX18.
Am most curious to compare the Futaba 18MZ as well as the top JR Transmitters specifically for this signal strength alone.
My friends keep saying that as the Futaba 18MZ is 4 to 5 times more expensive than the Spektrum, it will have a higher signal strength. Unfortunately Futaba does not display Fades--Frame Losses -- and Holds so there is no other way but to actually measure all the Transmitters at one go.

Len Todd

Just sending it back to Spektrum would insure it gets fixed correctly and is operating correctly. Seems like that would be a lot cheaper than getting a spectrum analyzer for 4.2 Ghz only to find that it needs to be sent in for repairs anyway.Most likely the repair would be free. I understand there may be shipping. But, once you analyze the signal, it should be sent back to Spektrum anyway.

ajay1

Over 15 of us at our field are flying Giant scale Prop / Jet models costing 8000 $ to 12000 $ each --- Nobody has a clue about the Rf Output signal strength of the Transmitters nor about the Rf interferrance / noise pollution levels present in the environment, past / current.

This one spectrum analyser will help all to be better informed.

czorzella

Please keep us informed about your progresses in that field of analysis.

vertical grimmace

My Feedback: (1)

I have a question about the voice feature of these radios. I am looking very closely at getting the new Stealth 18. Can you program the voice to say what you want, and then toggle it on command? The reason I ask, Is I am a competition flier, and it would be great to have that feature for calling out maneuvers in practice. Eliminates having to look down at a card.

BarracudaHockey

My Feedback: (11)

As of now, no.

AndyKunz

When we created the voice feature, one of the features we included as a stepped item intended especially for calling out maneuvers. There are two up-to-16-step sequences possible (to allow you to have known and unknown ready to use), and 32 custom voice options. We are right now running the audio package through beta testing, so it won't be too long until it comes out. When it does, you will have all you need right there.

Andy

BarracudaHockey

My Feedback: (11)

Nice!

I had heard that was in development but wasn't sure it was something I should share.

AndyKunz

I've been talking about it on RCG for a long time, but it's finally into a beta which is exciting news for me!

Andy

vertical grimmace

My Feedback: (1)

That is great news. This will be an extremely popular feature. I know guys that have fabricated such devices and attached them to their TX just for IMAC practice. This feature alone may sell you a radio or 2.

ajay1

Received my new Spectrum Analyser and measured the Rf output of my 2 Transmitters;---
a] Spektrum DX18QQ -21 Dbm [ Minus 21 Dbm]
This Tx was giving me around 1500 Fades in a flight of 10 minutes.


b] NEW Spektrum DX18 Transmitter - 10 Dbm [Minus 10 Dbm]
With the very same 4 model planes this Tx is giving only 40 to 50 Fades
in a flight of 10 minutes.

Both the Tx's have been kept exactly 12 inches from the Spectrum Analyser and scanned numerous times with Max Hold memory of the Analyser
displaying the above mentioned output readings.
Will compare the results of the readings from all the flyers at our field.

czorzella

Good work AJay,

That is an interesting finding, but it only suggests that the tested DX18QQ may be defective and should be serviced by HH.

If possible, when you test other radios in the field, please shoot a video of how you are making these testing.

Carlos

czorzella

AJay,

On a second thought, please clarify if your DX18QQ isn't EU compliant version which could explain the different power levels that you found.
It would also be interesting if you can share the graphs generated by the spectrum analyzer.

Carlos

AndyKunz

Be sure to report the RF PID as well.

Andy

Len Todd

You might want to consider trying your testing with the transmitter a bit further away to ensure against overloading the analyzer, If you get the same readings a few more feet away, then the analyzer's front-end should not be overloaded.

Good report though. When I talked with HH's Tech about my DX8, If I recall correctly he mentioned -10 being the top end (best expected signal) of their spec.