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kgfly

05-10-2007, 09:55 AM

I agree that many companies provide inflated claims to market their products and perhaps XPS is in that group.

However using the guidelines and figures from MaxStream's own website here (http://www.maxstream.net/support/knowledgebase/article.php?kb=90) we get:

Tx power = 20dBm
Rx sensitivity = -100dBm (at least for the stock XBeePro module)
Antenna gain = 2.1dBi x 2 (I think)
So margin = 20 - (-100) + 4.2 = 124.2dBm

It clearly shows, according to MaxStream, that the XbeePro is easily capable of a range in excess of 1 mile ground-to-air. Perhaps the Tx power is 18dBm and the antenna gain only 2dBi, but even then, the margin is over 120dBm which according to their table gives over 5 miles range. MaxStream further recommend allowing another 10-20dBm for other losses which brings us back into the 1 to 5 mile range and quite in line with XPS's specification which says "up to 5 miles". This is all just so long as RF LOS is achieved which MaxStream define as:

RF LOS is different that visual LOS. Visual LOS is present when one can stand next one antenna and use binoculars to view the other antenna. RF LOS requires not only a visual sight line between the antennas but it also requires that a football shaped area between the two antennas be free of obstructions.

I think that MaxStream are sensibly conservative in claiming only 1 mile range for the XbeePro in the datasheet, especially since typical usage will be ground-to-ground and they don't want to be accused of inflated claims :wink:

However I am confused about your concern that XPS claims anything other than LOS operation. I don't recall them claiming their system was not LOS. In their comparison table for "specified range" they list "line of site" for DSM2 and FASST products since that is the only information Spektrum and Futaba provide. Neither Futaba nor Spektrum specify a range. For their own system in this short form table XPS claim "up to 5 miles" which appears to be consistant with the MaxStream reference data. In their more detailed specifications they say:

Range (6 channel receiver)

* Up to 500 feet ground based, line of sight.
* Up to 5000 feet ground to air, line of sight.

Range (8/10/16 channel receivers)

* Up to 1 mile (5200+ feet) ground based, line of sight.
* Up to 5 miles (26,000+ feet) ground to air, line of sight.

So as far as I can tell, their claims are for LOS operation with ranges consistant with MaxStream's specifications and guidelines. All seems above board and reasonable to me. :dontknow

ClayK

05-10-2007, 01:36 PM

Maybe because they aren't using a totally stock Xbee module?

Do we know this definitively or are we speculating?

5000 feet isn't 5 miles. Why would the 6ch RX have a different specification than the others?

While I might concede the '5 mile range' (however, I am not), my problem is with the omission that their receiver is not subject to basic RF principles with regards to LOS. By the format of their comparison chart (which is missing the updated information on their competitors) they make a point of tagging their competitors as LOS restrictive, when their product has the same limitation.

I'm not a noob to RF engineering, planning and saturation. I realize that signal is not a physical LOS, I stated earlier that the signal degrades or is shadowed by objects, in some cases rebounded as in the case of some radios. My experience comes from cell platform design, placement and construction. I disagree with the argument of 'sensibly conservative' from MaxStream. Would this imply that XPS is neither sensible or conservative?

I also realize that the range is doubled based on some factors, but I haven't seen defined specs from XPS yet to help me validate/understand their claims.

Keep in mind I am awaiting the system for the 14mz, I'm neither close minded about their product, nor am I sipping the KoolAid.

fireup

05-10-2007, 04:08 PM

5000 feet isn't 5 miles. Why would the 6ch RX have a different specification than the others?

6ch RX uses a lower wattage module (1mW) while the others RX uses 100mW modules, that's why they have a higher range.

spork

05-10-2007, 05:55 PM

6ch RX uses a lower wattage module (1mW) while the others RX uses 100mW modules, that's why they have a higher range.

I'm confused. I'm not familiar with any correlation between wattage and reciever sensitivity. Obviously a higher TX wattage will give longer range. Am I misunderstanding something.

Motions

05-10-2007, 06:04 PM

ClayK

05-10-2007, 06:29 PM

kgfly

05-10-2007, 06:29 PM

kgfly

05-10-2007, 06:37 PM

6ch RX uses a lower wattage module (1mW) while the others RX uses 100mW modules, that's why they have a higher range.
I think your completely confused. The transmitter module is 100mW, not the receiver. The 6ch Rx uses a surface mount antenna rather than the dipole which reduces the range.

Ok, now I'm confused. The manual for the XPS system says to set the transmit power from the TX module by pressing and holding the PROG button (page 21 of 22). So what determines the power output, the receiver or the transmitter? I'm also confused because I can't find anywhere on XPS' site that specifies the 6ch RX uses a lower wattage module.

Do Spektrum tell you on their website why the AR6000 is "park flyer only" but the AR7000 is "beyond visual range". Why should XPS be obliged to tell you on the product datasheet the differences in electronic design ? That they have shared so much internal detail on the fora is unique and impressive IMO. In general most manufacturers do not tell you how the product works, just the specifications of different items and you choose those that best suit your application. Why single out XPS for criticism in this way ?

XPS/XL is a *bidirectional* system, both Tx module and Rx module are transceivers so you have to set the power level on both units except for the 6ch where the power is fixed. The only reason the power levels are adjustable is to comply with differing national limits on max radiated power for DSM devices. This is an issue that has caused Spektrum problems in Europe.

I would certainly agree that the XPS user manual needs a lot of work. XPS have already included several changes suggested by users and no doubt there will be further improvements.

ClayK

05-10-2007, 07:04 PM

The XPS system is unique amongst announced solutions in that it is fully bidirectional. Every packet sent by the Tx is ACKed by the Rx. If an ACK is not received within ~900us the packet is retransmitted, this is repeated until the next frame data is ready. The ACK carry information about packet loss and signal strength at the Rx as well as noise floor values for all other channels. If the packet loss rate gets above a threshold value, the Tx initiates a switch to the best available channel (as determined by the noise conditions at the Rx). The switch takes under 1ms to occur. Of all the current schemes (Spektrum=DSSS, Futaba=FHSS) this seems the best design so far. The downlink will also carry telemetry data from up to 255 daisy-chained on-board sensors.

I haven't quite made a decision on what the best design is so far because I haven't had all three in my hands yet. I do like the telemetry option, but it's not a make or break portion of the equation for me. I'm curious why you (Kenneth) believe it to be the best design so far? Besides the telemetry portion. The Futaba and Spektrum both seem to have adequate systems, but that's my opinion at this point.

To save weight, size and cost, the 6ch "ParkFlyer" Rx does not have the extra power amplifier carried by the other Rx. It also uses a lower gain chip antenna rather than a whip antenna.

I couldn't find that information anywhere, I'm sure it's posted on a forum. It's not the XPS site, at least as far as I could find.

It seems kind of harsh to interpret the XPS claims as misleading when they clearly state that the system is LOS and clearly state a difference between their 6ch Rx and larger Rx. So your big beef is that in a summary table they didn't mention LOS ? Really ?

My point is the omission from XPS that their system was a line of sight system when they were clearly pointing it out as a limitation of their competitors. Yes, I do have a beef with that. I also have a beef with the fact that they haven't updated Futaba's information or any pertinent Spektrum information. I believe it to be misleading, so I certainly believe it to my personal pet peeve. I can't understand why more people that know as much as they do, fail to find fault with this type of discrepancy.

Take a look at Spektrum's website and the many, many pages for DX6, DX7 and Air Modules. They never mention anywhere that I could find that these are LOS operation. They say that range is "more than enough" for the DX6 as a ParkFlyer system and "beyond visual range" for the DX7 and I couldn't find any range statemens for the modules but I stopped looking after wading through quite a few pages. Will you tar them with the same brush for being devious and misleading ?

They don't specifically list a comparison to their competitors, they also don't exclude information from their competitors that might hurt their market share. This is my opinion Kenneth, but Futaba and Spektrum don't claim questionable specifications, compare themselves with their competitors touting their superiority while omitting information or fully disclosing the specifications for each component or explain the differences and why. The difference, I think, between your view and my view is I am not blindly accepting claims or defending a product without a substantial basis to take that particular stance.

I fly Spektrum and think it's great. I applaud XPS for their innovation and so far their product looks even better. I don't believe everything I read and am waiting to see how the units perform in the field.

I am interested about all the systems either coming to market or currently in the market. If you read my posts, I am interested in XPS and considering purchasing it. I am concerned about all the hearsay floating around when it's not specified on the manufacturer's website. This discussion reminds me in so many ways about a stock called CMKX not so long ago. Investors claimed they knew this or they knew that. In reality, no body knew anything, it was all conjecture. The company never released anything. I'm not blindly putting faith into something when I can't justify or verify certain claims. I am simply questioning the claims and bringing to light MY concerns.

I do find it odd how folks seem so eager to read negatives into anything XPS present. So you are skeptical about their claim of "up to 5 miles" then fair enough, wait and see how it pans out in user's hands. I don't see any solid reason to accuse them of anything evil just from the summaries and detailed specifications on their website. So far there is no evidence that their claims are false. :dontknow

I already stated I am contemplating conceding the "5 mile" range claim, but not completely. Information from the manufacturer, listed on the site would answer such questions/concerns/etc. The manufacturer can display the specification without revealing their "secrets". I fail to see how revealing the component specifications and test data would jeopardize their "trade secret". I think it's important to point out that XPS is a newcomer to an established market. JR/Spektrum, Futaba and Airtronics have proven continuously that they are here for the long haul. They haven't "just" come out of the "woodwork" in the last couple of years. In that respect, I feel they need to prove something, substantiating their claims with the requested information would go a long way in "good faith". Like I stated earlier, I am already considering the system, so I am not "burning XPS at the stake" but merely bringing my concerns to light. JR/Spektrum, Futaba and Airtronics already have my trust and don't need to prove anything to me. Like I also said, I'm neither touting the manufacturers claims nor am I burying them for it. I simply want my questions answered. I'm sure others have either similar questions or different ones.

Motions

05-10-2007, 07:21 PM

I think the biggest problem IS that Jim and crew offered technical information about their product, probably more than they should have. This gives ammunition to the naysayers and started all the debates. If they had kept all their technical data to themselves, there probably wouldn't be all the heated debates.

You won't see ANY other company provided that much proprietary information anywhere. And you can also see there's not such heated debates on other 2.4GHz products.

ClayK

05-10-2007, 07:31 PM

The manufacturer can display the specification without revealing their "secrets". I fail to see how revealing the component specifications and test data would jeopardize their "trade secret". I think it's important to point out that XPS is a newcomer to an established market. JR/Spektrum, Futaba and Airtronics have proven continuously that they are here for the long haul. They haven't "just" come out of the "woodwork" in the last couple of years. In that respect, I feel they need to prove something, substantiating their claims with the requested information would go a long way in "good faith". Like I stated earlier, I am already considering the system, so I am not "burning XPS at the stake" but merely bringing my concerns to light. JR/Spektrum, Futaba and Airtronics already have my trust and don't need to prove anything to me. Like I also said, I'm neither touting the manufacturers claims nor am I burying them for it. I simply want my questions answered. I'm sure others have either similar questions or different ones.

Proprietary information is not the same as test data or detailed specifications. Proprietary data is how you make a particular component. I'm not asking for what circuit board is hooked up, nor am I asking how. I work for a government contractor and releasing our specifications and test data is a requirement. Your statement would be analogous to a car company stating certain claims, but then not telling you the displacement, suspension, brakes, etc. Basically, it's just a car company asking you to "trust" them. Whenever a car manufacturer brings some "new" technology to the market, they explain it sufficiently (use Vtec as a reference if you will). Last I heard, when Kia's and Hyundai's came to the market, they had to prove quite a bit. Posting test data and the technical differences (like the low wattage RX mentioned before) is not proprietary data.

As mentioned before, the other manufacturers have already established themselves. Should I also note that Futaba has been in the business for decades. Same goes for JR. Spektrum was critically evaluated when they first came out, support from JR helped them a bit. How is this any different with XPS?

Why is everyone up in arms about my questions? Is it because there isn't any specific information to answer my questions or is it because they are scary?

Motions

05-10-2007, 07:44 PM

Clay, XPS is brand new and basically unproven so the attacks are easy. To tell you the truth, I think XPS is actually learning the specs of their product as time goes on. Look at the antenna mod for example. I honestly think that there is no concrete data at the moment or at least not that Jim will reveal yet until it is concrete.

If you happen to follow the enormous bashing thread on RCG, it's easy to see why XPS is weary to cough up too much to the public.

kgfly

05-10-2007, 08:02 PM

OK, thanks Clay, I understand your point of view more clearly now :hug:

I'm curious why you (Kenneth) believe it to be the best design so far?
Spektrum's solution uses frequency, antenna and spatial diversity to ensure a robust link. It is unidirectional and locks on to two fixed channels at power-up. If the model encounters sustained noise on both of those channels it has no next-level response. The need to scan through 80 logical channels and lock on to the two in use by the Tx means that their Rx reboot/reacquisition time is long (several seconds) so brownouts typically lead to catastrophic failure. The majority of evidence from the field is that power-supply failures are the leading cause of lost models flying Spektrum radios. While this is highlighting that the problem is primarily with the power supplies, the slow recovery of the Spektrum Rx makes them much more susceptible to the problem than the FM Rx they are replacing or the XPS Rx (see below).

Futaba uses FHSS rather than DHSS and two antenna for diversity. They have not released any technical details AFAIK nor have I seen much info about their response to brownouts so for now they are mostly an unknown. I believe that while gaining frequency diversity with FHSS you lose some processing gain compared to DHSS which translates to lower sensitivity, but I could be wrong about that detail.

XPS uses as-needed frequency diversity based on dynamic and continuous monitoring of the RF conditions *as experienced by the Rx*. That seems superior to Spektrum which selects its channels at power-up time based on the RF conditions experienced by the Tx which may or may not be representative of what the model is seeing once it is in the air.

XPS allows for the use of multiple Rx to achieve antenna and spatial diversity should the individual modeler feel it is needed, although so far XPS have not found a case where it has been required.

Being bidirectional, XPS is able to use ACKs to drive retransmissions. If Spektrum or Futaba lose a single packet then that frame is lost and at best the aircraft will receive the next frame resulting in at best a 40ms gap between updates vs the expected 20ms. With XPS a lost packet will be known to be lost and a retransmission is sent in under 900us. So at best the frame update will be achieved in 21ms compared to the expected 20ms. Now I am not sure if all three use exactly 20ms updates between Tx and Rx but this is a convenient baseline to illustrate this benefit of the bidirectional link.

The key is that the bidirectional link used by XPS gives them the combination of the higher sensitivity (as I understand it) benefits of DSSS while their "intelligent" hopping gives them the frequency diversity benefits of FHSS. In addition, since their Rx only has to scan 12 channels and acquire one, their reboot/reacquisition time is only 90ms (recently qualitatively but not yet quantitatively confirmed by end users) which means brownouts tend to lead to hiccups rather than crashes.

And of course there is the yet-to-be-released telemetry feature.

So in theory the XPS solution appears to offer:
* The sensitivity of DSSS
* The frequency diversity of FHSS
* The option of antenna and spatial diversity
* Dynamic channel selection based on RF conditions at the Rx in flight
* A higher probability of achieving the best possible frame update rate (via re-transmission)
* Very fast reboot/reacquisition
* Telemetry

That is why I think it appears to be a better design than Spektrum or Futaba.
---------

It is quite true that I have not been able to confirm all these differences myself. I don't have the resources to do that and am relying on information from the large and diverse body of end users sharing their experiences with these various products to help me decide which manufacturer's claims to believe.

---------
Clay I will certainly be very interested in your assessment of all of the spread spectrum solutions that you choose to buy and evaluate.

ClayK

05-10-2007, 09:18 PM

I tried to read the rcgroups thread, but found the thread to be more argumentative than inquisitive. I'm looking for answers, that's all I want.

Your explanation of the retransmit and clarification of the baseline example was extremely helpful. I suppose the question is, what is everyone's transmit cycle? I'm curious on what Futaba's and Spektrum's 2.4 signal cycle is. This would allow me to compare it to XPS' transmit speed. The only other question, in addition to the others mentioned previously, is why doesn't XPS list this type of information on their site? If it is on the site, where is it? (I can't find it)

I'm interested in the latency results between all the manufacturers. I'm equally interested in what Futaba modules/receivers will use 2048 resolution. From the statements on their site, one can infer that only the big dog 14 channel receiver will have that capability, however, I can't confirm that yet. That's a mark in the con column as far as I am concerned, if the latency is the same between all the receivers for XPS, that's a pro in their favor (provided it's low overall). Some may say that latency is an advertising gimmick, but I know the difference between my model on a 14mz and an identical model on a 9c.

Bottom line, I just want to be an informed consumer. I've made mistakes in this hobby as well as in other facets with regards to financial decisions, I prefer not to make that mistake again. I ultimately want the best system for my money that meets my requirements. One of my requirements at this point, is answers to my questions, from all manufacturers.

DavidH

05-10-2007, 10:35 PM

To tell you the truth, I think XPS is actually learning the specs of their product as time goes on. Look at the antenna mod for example

So does that mean that the customers that paid money for the product is also the Beta Testers?

David

Motions

05-10-2007, 10:55 PM

Now tell me what RC product doesn't do that. Hell, look at Align, everybody that owns a Trex is a beta tester so they can make new upgrades every week. :mrgreen:

fireup

05-10-2007, 11:04 PM

The only other question, in addition to the others mentioned previously, is why doesn't XPS list this type of information on their site? If it is on the site, where is it? (I can't find it)

The comparison table is at the bottom of the main page: http://www.xtremepowersystems.net/

Some of the comparisons are misleading... such as the Resolution. I doubt XPS is capturing the PPM at 16 bits and spits it back out at 16 bit also.

I suppose the question is, what is everyone's transmit cycle? I'm curious on what Futaba's and Spektrum's 2.4 signal cycle is. This would allow me to compare it to XPS' transmit speed...

I'm interested in the latency results between all the manufacturers...
.

The transmit cycle depends on how big the packet size are. As far as transit speed, XPS sends out at 256Kbps while DSM2 is 128Kbps. All claims that one cycle time is within one frame rate (16ms - 20ms) (except DSM1). But the big advantage XPS has is bi-directional communication. This means if a packet is lost, the packet can be retransmitted again within the same frame rate. DSM2 and Futaba require multiple antennas to get redundant data. If all the data don’t get through to all the antennas, then it will have to wait for the next frame, which will affect latency.

6ch RX uses a lower wattage module (1mW) while the others RX uses 100mW modules, that's why they have a higher range.
I think your completely confused. The transmitter module is 100mW, not the receiver. The 6ch Rx uses a surface mount antenna rather than the dipole which reduces the range.

Yes, the transmitter module uses the 100mW module. The 8 ch and higher RX also use this module, but the 6ch RX uses a less powerfull module.(I'm assuming of cource base of the photo of the recievers below). Looks like the 6ch uses xBee (1mW modules) and 8ch and up uses xBeePro (100mW modules). Also, I don't see the chip antenna for the 6ch you're talking about? Do you have an updated picture of the 6ch version?

spork

05-10-2007, 11:07 PM

So does that mean that the customers that paid money for the product is also the Beta Testers?

Companies prefer to call these folks "early adopters". They are generally a very special crowd in that they're very enthusiastic about the technology, will pay more, and are far more understanding of things like recalls for antenna re-design, poor documentation, poor UI... And they're typically more willing to figure some of the issues out for themselves.

This is one of the reasons the Ipod only worked on Apple computers at first. Until it was fully wrung out, they wanted to limit sales to a friendlier (to Apple) crowd. I think they handled that very well.

kgfly

05-10-2007, 11:23 PM

Clay - Finding the detailed information is indeed difficult, it is buried in amongst about 15,000 posts across RCG, RR, RCU and HF. I think I have read them all but I might have missed a couple :wink:

I agree that having more insight into the details helps with comparisons, but of course that's not what any of the mfrs want and so none of them really publish the kind of detail you are seeking, except where they feel a given aspect differentiates them from the competition.

As for latency, well indeed that's an interesting one. The first batch of XPS performed worse than their claimed PPM+2.5ms but the updated firmware which they say has a fix for this has yet to be tested. As always, keep an eye no the first post in this thread for JohnK's CCPM latency measurements: http://www.runryder.com/helicopter/t172571p1 It will be fascinating to see how the Spektrum and Futaba modules stand up in this comparison.

"what is everyone's transmit cycle" - well darn it I did see that somewhere but now I cannot find it. The answers are out there... :lol:

Some of the other feature benefits of XPS over Spektrum and Futaba include:

* 16-bit (65535) resolution (exceeds the abilities of current Tx but it's there)

* Failsafe programmable per-channel as either Hold or Preset

* Channel mapping in the Rx. This lets you decide which plug will be which channel (can be helpful if you have servo cable length issues) or associate multiple plugs with one channel (eg have multiple servos per control surface without Y-cables).

* The next version of Tx-modules and Rx (probably some months out) will be field upgradable so future firmware upgrades will not require return-to-mfr. XPS have offered a free hardware upgrade to anyone that buys first generation units if they send them in.

* The 16ch Rx is slated to have full matchbox features and be configurable via the onboard OLED display.

David - To a degree yes, but it would be naive to think that doesn't happen widely or that no matter how much testing a mfr does, problems will not still be found once a radically new product gets into users' hands. I understand the 14mz had serious problems at first release and went through 2 or 3 firmware upgrades very early in its life. Similarly the G3 Rx. The AR6100 Rx was found to have a problem in the first few weeks of wide distribution and has had a firmware upgrade. The CC escs had serious bugs in their first generation.

This is not suprising for any of these new products and the real question is how the vendor handles it. XPS have been very open about the problems, advertising them widely as soon as they were found, creating fixes within days and offering free upgrades to all existing customers. I would say they have responded to the issues extremely well.

IMO anyone that chooses to be an early adopter should expect problems and if that doesn't suit then instead they should wait for a later generation of the product which is likely to have the wrinkles ironed out.

kgfly

05-10-2007, 11:47 PM

I doubt XPS is capturing the PPM at 16 bits and spits it back out at 16 bit also
Why do you doubt that if that is what they say they do ? Do you also doubt that Futaba do it to 15-bits in their Tx module ? Remember these bit-counts are the resolution of the channel data sent between Tx and Rx, not necessarily the resolution of the host Tx.

The CPU XPS use (sorry, I have forgotten the part number) certainly has fast enough counters to do 16-bit resolution on the PPM pulse measurements. Remember they are not doing A/D conversion, simply sampling a PPM pulse to measure it's length. That is not hard to do at the claimed resolution.

However no matter how precise the sampling of the pulse, the resolution of the Tx that sampled the sticks and created the pulse is the limiting factor. This ranges from 8-bits on an Optic6 to 12-bits (I think) on a 14mz. XPS address this issue in their FAQs. If they build their own Tx they can then choose to give it 16-bit resolution from the sticks all the way to the Rx.

Looks like the 6ch uses xBee (1mW modules) and 8ch and up uses xBeePro (100mW modules). Also, I don't see the chip antenna for the 6ch you're talking about? Do you have an updated picture of the 6ch version?
Correct, the 6ch uses the xBee and the Tx modules and other Rx use the xBeePro. In all cases XPS claim that there are some undisclosed/proprietary modifications and that these are not the stock MaxStream modules. There is no photo of the new 6ch Rx with the chip antenna since it is still in development. XPS are saying a few more weeks. One area where they have a track record of failing to meet their promises is release dates (hardly unique to them though!) so don't hold your breath. I am sure it will be released but it might not be soon.

ClayK

05-11-2007, 08:25 AM

"what is everyone's transmit cycle" - well darn it I did see that somewhere but now I cannot find it. The answers are out there... :lol:

This is the type of information that I would expect on the comparison chart. That and updated information on the competitors. Much like Progressive Insurance lists their price and the price of their competitors without any embellishment. If, in reality, the product is better it will show on that chart.

I attempted to read the 700+ page thread(s) and it was terribly frustrating. I'm not trying to bust on you, but I remember hearing "the answers are out there..." on the CMKX roller coaster, when no such information actually existed. Rather than attempting to piece together definitive information from forums (much like CMKX), I'd rather hear it from the horse's mouth. Having this information on the manufacturers site makes it empirical, there can be no question in my mind, especially if the comparative analysis is qualitative. I am sure you and others have important information and it may be valid, but seeing it from the company makes it "more real". I suppose there is some sort of accountability if it were listed on a specifications/results page on the XPS site. One would think (and maybe this is just me) that if people were asking you (the manufacturer) questions, rather than answering them on the forum exclusively, the manufacturer would post those answers and possibly those questions on their site for easy accessibility. One-stop shopping if you will. This would inform the consumer directly rather than relying on "some forum" to maintain that data. Much like my questions on Spektrum modules and Futaba modules, I want to have comprehensive results with a comparative analysis. I am sure I can pony up a little bit of money to "test" the 14MZ module and receiver, but I'm not going to convert my fleet (7 models) until I can cover all my bases.

capebob

05-11-2007, 03:21 PM

After a nasty bout with the flu I finally got my XPS system in the air today and it performed flawlessly in my R50 and I didn't have to wait for my frequency. I flew the helicopter as far away as I dared and I noticed no unusual characteristics. Guys, I think that's the bottom line. You all can go play with your numbers all you want, I'm going flying. :D

Bob

spork

05-11-2007, 05:47 PM

You all can go play with your numbers all you want, I'm going flying. :D

The hobby is different things to different people. Electronics, RF, mechanical, aero, scale, building, tuning, even flying, are all good aspects of R/C helis. That's one of the things that make it so fun.

capebob

05-11-2007, 06:56 PM

That's what I said. You can go play with your numbers all you want, I'm going flying. We have a member in our club that doesn't fly anything, but he still enjoys being around the hobby. I didn't mean it as a put down.

Bob

spork

05-12-2007, 12:50 AM

I didn't mean it as a put down.

Sorry, I thought it was intended as "sort of" a putdown. I jumped the gun.

On a separate note, I grew up just a few miles south of you (in Naples). Kind of miss it.