Shiftyeddie

My Feedback: (9)

I have a few orangerx satelittes and was wondering
if anyone has tried plugging them into Spektrum
receivers?

I have a ar9000 dsm2 Receiver with 2 satellite ports.
If the Orange rx would work it would save me having to
buy a spektrum satellite.

allans

My Feedback: (11)

I have never seen one that could pass a range check. Be careful

Mpizpilot

My Feedback: (45)

All I fly is orange rx's now and have never in over several hundred flights had a single issue.

JWQ500RC

My Feedback: (2)

I have two planes using the orange satelittes, and have no problems in well over a year of use. Both are used in AR7010 receivers.

Aerocal

DSM2(kinda sorta wannabee) sats on a DSMX main Rx.[X(] What does your FL data look like?

Franco2fly

I'll bet that an Orange Sat rx plugged into a Spektrum DSMX receiver is NOT providing the RF diversity.  I'm not even sure I would trust the Fade and Hold output readings.  Now it MIGHT work if the Spektrum Rx is a DSM2 receiver.  My feeling is that if you are comfortable flying DSM2 just go ALL Orange....  I've never had a glitch with any Orange product.

KKKKFL 

Len Todd

What the heck has RF Diversity got to do with it? I have been a ham for almost 40 years and never heard of that term being used in this type of situation.

It all boils down to Rxer sensitivity. If you have a 2.4 Ghz RF signal generator/RF monitor, technically one could accurately determine the Rxer's sesitivity. Unfortunately, this particular RF equipment is still fairly expensive. Also, w/o the Rxer's schematics, it would take some detailed and intricate investigation to identify the correct test points on the Rxer. So, we in the field are typically limited to a full scope range check before the flight and looking at Flight Log Data either during or after a flight.

If the Rxer sensitivity is down on an Orange Rxer, the Fades, Frame Losses and Holds would increase at or near the what was typically the frindge of the Transmitter's range. Given the collective nature of the Flight Log data, it is most-likely complied at the Main Rxer. So, if the Orange Remote Rxer was not working up to snuff, you would see that fairly quickly in the Flight Log.

Bottom line: If you can fly the plane out as far as you used to before the Orange Rx, then you are good to go with one.

Personally, if I am flying small planes, the orange Rxers may do just fine. Small planes typically fly in close. Of course, we typically tend to not put in multiple remotes, etc. on small planes because of the lack of space and we are flying in close, etc.. However, when I am flying $4K Giants, way out there, then I personally tend to shy away from any unnecessary unknown variables, which an Orange Rxr is to me. But,... the fact is; there are those of us out there that would risk an expensive plane, just to save a $, and it is a free country. I know those people are out there. I used to be married to one.

AndyKunz

On HAM bands you don't have to worry about antennas being shadowed. The wavelengths you are accustomed to are many times what 2.4gHz users are utilizing. Thus, your HAM experience and knowledge may not transfer directly across, although it certainly helps some.

As for sensitivity, I guess you could say that if 2.4gHz rx's were so sensitive that they could still detect a signal that normally might be -100dB and suddenly it's -200dB then yes, you could probably say it's all about sensitivity. In that case, it's blatantly obvious that multiple receivers, physically diverse in their locations and orientations, could provide a signal path despite N-1 antennas being shadowed.

Andy

Len Todd

With all due respect Andy, 2.4 Ghz is also a UHF ham radio band. One particular application that comes to mind is our Moonbounce activity. However, with moonbounce we are typically dealing with Rxers that appear to be more sensitive than a RC Remote Rxer. Then, we add in pre-amps, and phased arrays of high gain directional antennas, etc.. We also add in RF diversity as some of this type activity using satilites uses one band to receive and another to transmit on. This is not to say RC Rxers are bad, because they are not. From what I have experienced, Spektrum’s remotes are also pretty darned sensitive. By the way, what is the Sensitivity Spec for one of Spectrum's Remote Rxers anyway?

In the past, I have designed, installed, tested and maintained public warning systems using digital RF communications with error checking protocols, etc. on UHF frequencies. I used to have access to the type of test instruments I mentioned, which I used to install and troubleshoot with in the field for a living.

As a Ham, I was into X.25 and other protocols, with error free digital communication on UHF and VHF bands in the early 1970s, long before it was even known as digital communications and there was a number on the protocol. We used to design and build our own wire wrapped boards in those days. You could not buy a black box that could digitally communicate to save your life. Eventually we called it "Packet Radio."

There are also several other bands of ham UHF and VHF frequencies below 2.4 Ghz that are affected by "shadows" and other such effects. I was the State Frequency Coordinator for several of these bands and also had several repeater installations that I designed, built, maintained, owned and/or operated, both using digital and voice modes. We designed these with remote Rxers to overcome the effects of shielding and shadowing of mobile and portable units. Only our remotes had RF links back to the main signal processors versus hardwire networks. So, please do not discount my RF experience. I am kind of thin skinned about that tonight for some reason. I was not challenging anyone. I just was trying to learn about what the poster was getting at with “RF Diversity.” Maybe I need to work on my delivery?

As to your technical comments: Last I knew, PHYSICAL diversity, which you brought into this, and RF Diversity are two different aspects of RF reception. I believe in Physical diversity. That is why both my Giants have AR 9210s. You guys have me convinced on this. It not only addresses physical shielding as you suggest, but also addresses cross-polarization of antennas (i.e. cross-polarization at these frequencies typically reduce the signal by ~30 Db.) But physical diversity is not what was mentioned. Maybe you were thinking Spread Spectrum is RF Diversity, which in a way is correct. But really it is only a single transmission mode. I was thinking one would have to use more than one mode or band (versus Frequency) to achieve true RF diversity. But maybe not. I guess RF diversity could be kind of relative.

As you know, a loss of signal of 100 db is relatively “astronomical” considering 3 db is a 50% reduction in signal strength. It certainly does not take a 100 dB of signal loss to initiate a Fade. A Hold, I could understand a 100 db change being appropriate. I could be wrong here, as I have not made physical measurements. But, some common RF sense tells me I am probably correct.

Personally, I correlate a Fade as being recorded every time the main processor is forced to vote (i.e. switch Rxers). I view that vote as being caused by a slight reduction in the currently chosen Rxer’s captured signal and an alternate Rxer simultaniously having a stronger signal present. Consequently, the fade is recorded and the stronger signal is used. We have done it in the RF world this way for 3 decades only we really do not bother naming or counting the fades. But we did occasionally analyze the voting to determine if a particular Rxer was losing sensitivity, etc.. It may not be in your terms, Andy. But that is how I can correlate what is going on in our black boxes, based on my experience. Is this a valid correlation to what is going on in our RC receivers with remote Rxers?

While Spektrum sees physical diversity as an answer to reducing the effects of signal loss, antenna system gain and increased Rxer sensitivity could also be answers for further improvements. For example: Given the same placement of a remote Rxer (Spektrum or Orange) with the same antenna configuration and placement, the Rxer's sensitivity is the most-likely RF variable left to dabble with. Or, antenna configuration could also be changed to increase gain (e.g. using collinear arrays versus a ¼ wave or dipole antenna.) Of course there are physical limits to all aspects involving RF (e.g. you can only get so much gain out of any RF component, etc).

I have seen what I feel was reduced RC remote Rxer sensitivity in the field. No matter how or where my friend placed one remote Rxer, it consistently recorded nearly three times the fades. It would bind and the system did not show a hold, etc. Just the fades on that one Rxer were up. We replaced it and the fades were then fairly consistent with the other remote. Given that it would still bind and appear to be working, my conclusion was the replaced remote Rxer was simply losing sensitivity. He may still have that Rxer. If you like, I could maybe ship it to you for further testing.

Bottom line: You are right that physical diversity (i.e. antenna placement and polarization) can help our casue. But no matter how you package the data, no matter how or where you place the antenna(s), if the Rxer is not sensitive enough to hear the captured signal, it can't decode the data. In other words, decreased Rxer sensitivity = decreased usable range, and that is where I thought this thread was heading (i.e. differences between the Spektrum and Orange Rxers’ ranges). After all, the end user can match any remote Rxer’s placement and antenna orientation, but the Rxer’s sensitivity is the only RF variable we as endusers can not change. So if the placement and antenna config is the same and a Rxer's range is shorter, the casue is most-likely the Rxer's degraded sensitivity.

So much for the RF 201 course!

AndyKunz

Sorry, Len, I thought you were over-simplifying things by the "It all boils down to Rxer sensitivity" comment. My comment was in the vein of "yes, sensitivity is important, but immaterial if there's no signal to be sensitive to" which should explain why I dragged physical diversity in (which as you correctly noted takes care of both shadowing and polarization and multipath issues). Both frequency diversity and physical diversity are important, but they address different issues and complement one another when both are used.

As for RF 201, I tested out of it in college Electronics was another of my hobbies growing up.

Andy

Len Todd

Good to know who knows what and what they are thinking when they say whatever. Eh?

I could see where my comment might have needed further explanation, so I took the time to do that. Thank you for doing the same!

Unfortunately, with RF there seldom is an easy short answer. Especially among the tech types.

Also, when trying to pass on an answer to some of these questions or question comments, Speed Killsssssssssss.

I do not envy your position. As always, thanks for responding.

Shiftyeddie

My Feedback: (9)

I hooked up the satellite to the receiver and it locked on immediately. I have an additional spektrum

Rob2160

Now you have...

This was an Orange RX - 2.8 kilometers and working perfectly... My experience is the Orange RX's (Both Spektrum and Futaba versions) have identical range to the original items.

I am pendantic and obessive compulsive about my range checks and check every new item this way before I trust them in aircraft or Helicopters..

[youtube]http://www.youtube.com/watch?v=PPIWgfgvxAU[/youtube]

The only drawback using an Orange Satellite is that they are only DSM2, if you want to take advantage of the DSMX protocol you will need the Genuine Spek Satellite (DSMX is far superior to DSM2)

Rob2160

I think he means that the satellite might be sitting there dumb and idle and not actually doing anything...

I can vouch for the advantantage of diversity of multiple aerials with satellites, I did some extensive testing (non technical testing - real world range tests out to 5000 meters, and with an RX and satelltie arrangement with 4 receiving aerials, you only need a single aerial to have reception and the whole system works..

I did this by sheilding all aerials at extreme range and exposing each one individually thereby assuring myself that each aerial was actually working.

The stuff works.. I like the idea of satellites, especially with carbon fibre helicopter frames, with satellites I can arrange the placement so that at least one aerial is fully visible (usually two) at any orientation..

Len Todd

As I understand it, the system really only uses one Rxer at a time (i.e. It does listen to all of the Rxers, compares the signal qualities and then uses the signal with the best signal quality.) If it was using the signals from more than one Rxer at a time, the harmonics could render the system unreliable. When it sees a better signal than the one it is currently using, it records a fade and switches to the Rxer with the better signal. In the RF world we call this swap "voting." We do not bother recording fades. But for RC purposes, the Flight Log data is priceless to monitor our systems RF performance. We can see and measure it w/o an expensive test instrument.

I belive very strongly in multiple Rxers. I have AR 9210s (3 Rxers) on both my Giants.

Rob2160

That's interesting,I didn't know that.. Thanks for clarification..Most of my testing is non technical, just looking for results in the real world...I figure if it worksat 5000 meters, in all orientations then its good enough for me...

Len Todd

Rob2160:

I agree with your thinking, up to a point. It is nice to get less expensive products that will do nearly the same things. However, here are some alternate thoughts:

One of the key reasons we can not get good documentation on our Spektrum stuff is Spektrum/Horizon are afraid that someone will come along and copy their products. With the documentation in hand, it would be really easy and cheap to not only copy the hardware, but figure out how the software works. Consequently, we pay a heavy price every time someone buys a cheap knock-off (i.e. None of these manufacturers are willing to provide good documentation on their products.)

Also, I have almost a couple dozen different planes and helis. I have had a few problems with a couple of them. Horizon Hobby (HH) has been wonderful ensuring that my problems are solved, my broken stuff is fixed in a timely manner and good working order, etc. etc.. They also do really well stocking and shipping replacement parts. If most of us started buying knock-offs all the time, how long would you expect HH's current level of service and supply would last?

Also, last but not least, I have bought from Hobby King (HK) once. I had a problem with a servo. I ended up just throwing it away. Where do you even go for service with HK? Back to China? I know you are a bit closer, but your are still a long ways from "Orange Country." But then the Oranges Rxers are so cheap, I guess you could just throw it away when it fails, and buy another knock-off. Right?

<o></o>

Disclaimer: I know things are different in each different country. The above is just how I personally feel about all these knock-off products that are taking our technology and jobs and making a quick dollar off our research and design work. Without adequate documentation, I can't even verify what I previously told you was 100% correct and that kind of irritates me. And, ... as long as we keep buying the knock-offs, these rouge manufacturers will continue providing them.

Just some food for thought!