RE: CA Jets 2010 photos etc.
Rick's Victory has a Graupner G-booster G-160, JR8711 servos for all surfaces, carries over 1 gallon of Jet-A, and uses HUGE Nicad packs in the nose to obtain the proper CG. AUW is 47 pounds - wet.
Posted on: 10/4/2010 12:39 AM by Author "JimDrew" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=10045833

RE: BEST IN THE WEST JET RALLY!!!!!!!
Hey Lowell, Scott and I will be there with both kero and electron burners. We want to attend the banquet.
Posted on: 9/16/2010 1:05 AM by Author "JimDrew" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=10005737

RE: BEST IN THE WEST JET RALLY!!!!!!!
Well, if you are going to stick with facts, then let's do so. Due to our 400 foot ceiling (an FAA requirement because of being so close to the Chino Airport), we had to use a race track pattern for our speed runs. At E-Jets they used a 800 foot split-S dive to obtain their speeds. Yes, there were prop planes! I flew several large 3D planes, along with my Habu, S2 Cub, and other toys we brought. It was a great time! I look forward to hanging out at the Best of the West, seeing the Col. again, and giving to a great cause! Cheers to Joe for putting this one on!
Posted on: 9/15/2010 5:28 PM by Author "JimDrew" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=10004726

RE: A123's straight into receiver
I looked up the part number of the LDO regulator they use in the 6014, and it has a maximum input voltage rating of 16v. No calculations required. :)
Posted on: 6/25/2010 3:22 AM by Author "JimDrew" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=9825708

RE: A123's straight into receiver
I talked with Bill about it the issue, because we are a distributor of A123 products in the U.S. I posted the link because others also got the same answer. Call Futaba service yourself if you want to hear it with your own ears. :)
Posted on: 6/25/2010 1:05 AM by Author "JimDrew" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=9825583

RE: A123's straight into receiver
http://www.rcgroups.com/forums/showthread.php?t=1248090&highlight=a123+futaba#post15152541 Contact Bill Baxtor, head of Futaba service for Hobbico. Interestingly enough, the voltage regulator used in the 6014s we have here will handle 16v, which is why our specifications chart shows this as Futaba's max input voltage being 16v.
Posted on: 6/24/2010 1:49 PM by Author "JimDrew" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=9824392

RE: A123's straight into receiver
We have been a U.S. distributor for A123 products for over three years. In that time we have had only three packs (two 2300mAh and one 1100mAh) fail. All three failed CLOSED (not open circuit), so the voltage appeared as "low". I do not know if they always fail closed, but these three did. Out of thousands of packs we have sold, I would say this is an incredibly good reliability rate. A123 packs work with MOST (but not all) servos and receivers. Futaba has issued warnings about using more than 5v with their 2.4GHz receivers. Futaba owners might want to check into this before investing in A123 packs. A123 packs can be paralleled by plugging them directly into the receiver bus without any type of regulator. All ground (-) and power (+) pins on receivers are tied together. We recommend plugging one into your "battery" port, and another into an empty channel (or through a Y-cable if no empty channels are available). This does two things: adds redudency, and doubles the current capability of your servo bus. Keep in mind that servo pins are only good for about 5A, and the connection really depends on how many insertions/removals you have done. Yes, there is a life cycle on the female connector that plugs into a receiver. So, if you have a jet that uses 14 servos and each draws 1A, you have technically exceeded what the servo bus can supply (before experiencing some amount of voltage drop), even with two A123 packs. The A123 packs themselves will never be an issue for power. Your wiring would burn up long before the A123 packs ever got remotely warm. Considering you can start your car in the dead of winter with the A123 packs (there is a video of that on YouTube), you don't need to worry about the A123 packs being inadequate. I would NEVER use any type of regulator system, and A123 packs allow you to avoid unnecessary hardware that is prone to failure. We don't use switches either. We use a pair of Deans connectors. You plug in the Deans as your "switch". All of our jets (and we have a lot of them, EDF and turbine) all use dual A123 setups.
Posted on: 6/23/2010 12:06 AM by Author "JimDrew" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=9821046

RE: RADAR Speed Guns
We use a Stalker Pro for our testing. It has incredible range, which is the key to accurate radar performance. If you can radar the plane safely with nearly zero angle, you will have the highest degree of accuracy. The Stalker Pro sees 1/8th scale and larger jets fromn well over 100 yards away. You can watch the speed change in real time, with the peak speed also shown on the display.
Posted on: 6/2/2010 1:14 AM by Author "JimDrew" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=9774347

RE: CA Jets 2010 photos etc.
We have not been back since 2007 due to date conflicts with Toledo. Thank you Kenny for switching the date so that manufactures could come back to the best jet event in existence! It was nice hanging out with people we met years ago and getting to know them better, as well as meeting new people. Jill was still the amazing and ever patient registration coordinator. Dave and Kenny shared some stories that we will never forget! Doug Anderson, Ron Long, David Searles, etc. etc. it was great to see you and watch fly. Mr. Joe McBride - thanks for letting me call for you (although I love to watch the A10, helping protect it from getting smacked was an honor). Paul Reese - nice chatting with you! I can't wait to see the next CA Jets video! I would like to say a special thanks to David Shulman who threw on one of our shirts and flew our super fast (203MPH) EDF during the noon-time demo! The reaction of the crowd told the story! The awards presentation format was absolutely outstanding! The nominee and winner format really makes a lot more people than just one feel like winners! I just can't say enough about the event. We will definitely be back, and hope to come back to the Willow (with our turbines this time too) whenever an event is scheduled. Thanks again to all!
Posted on: 3/28/2010 11:12 PM by Author "JimDrew" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=9620054

RE: Heads up JET JOCKS!
[quote]ORIGINAL: AndyAndrews They couldn't outlaw them without legislation. And even then the states would have to chime in. Moreover, there would be grandfather clauses and the like. It would be no easy process but I guess it could be done if they tried hard enough. Still, good luck enforcing it on a state by state basis. [/quote] I got news for you... if the office of Homeland Security (which has juridiction over nearly every major branch, including the FAA) says that turbines are banned, then they are banned. No type of legislation will be required. Much like they can close any airport at will. We have been in contact with the Homeland Security office for nearly 5 years because of our radio system. When you have 5 miles of range and bi-directional communications capabilities, it causes a red flag, and they contact you. We are required to report any person requesting extended range, certain types of telemetry sensors, contact from certain countries, and other "things" that we can't talk about. About 2 years ago, there was a push by the FAA to limit the control distance of model aircraft to a maximum of 3000 feet. After testing was conducted, it was clear that all full range systems were working well over 1 mile, so that makes it difficult to have some sort of blanket policy, however, that is still being talked about. We have known about the potential turbine ban now for about a year, as the FAA has it on their list of things "to do". When the FAA presented the idea to the AMA, the only argument the AMA had against the ban was that "it might cause a hardship for some businesses". We are the U.S. distributor for Graupner turbines, and although it won't cause a problem for our business, this will cause a problem for our hobby.
Posted on: 3/11/2010 11:55 AM by Author "JimDrew" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=9572900

RE: Desert Jet Storm Photos
It was great to see some familiar faces. It seems like every jet event in the last 3 years has conflicted with a trade show. This year, nothing conflicts! Joe McBride - always an honor seeing you fly. Ron, UJ, Jake, Al, Terry, Jim, Bob, Tim, Daroll, et. all, great to see you guys again. Shui, I will put something together, if not for Florida, then for some other event. :) Speedworld was incredible, and the event staff was great! Thank you so much! We had never been to that facility before (due to conflicting schedules). We will be back!
Posted on: 2/15/2010 9:55 AM by Author "JimDrew" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=9506074

RE: For the record....
Nice job, Dave. We had no doubt that this airframe was able to obtain these speeds safely.
Posted on: 1/25/2010 7:07 PM by Author "JimDrew" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=9447644

RE: Aero Works P-51?
By the time you buy the TopFlight and a set of Sierra gear, you are not far off from the Aeroworks pricing. Of course, you would be missing the sequencing gear doors and retractable tail wheel too! We typically pay about $150 to have our jets setup with the gear and gear doors pre-installed at the factory. This is the biggest headache and worth every extra penny! With this Mustang, it's completely installed, plumbed, and ready to use. Flight times with the 12S 5000mAh setup depends on how you fly. We fly about 5 minutes agressively (nothing but full throttle burners down the deck). With 6400mAh you could fly some scale and some burners for over 8 minutes. If you want to putt around the sky, then quite a bit longer. The plane takes off at 1/3rd stick and flys just fine on 1/4 stick. We did the Solo 24" 4 bladed prop on the TopFlight version. We learned really quick that electrics have substantially more torque than gas will ever have. You can easily spin this prop, but the P-factor is so great that stabbing the throttle WILL rotate the fuse on the prop! It makes it a handful for takeoff, and forget stabbing the throttle to abort a landing - you'll be upside down before you can blink. You could put a delay in the throttle to simulate a gas engine and that would greatly help. The prop looks incredible while flying, but the reduced speed and the potential for disaster if you stab the throttle is not something that we wanted.... and we wouldn't ever add a delay to the throttle! :) The hatch was easy. Just cut two vertical slots and then cut the hatch horizontally . We use a Monokote hinge, and currently tape the hatch closed. We are going to add a simple hatch latch that can be opened from the cockpit or one of the fake exhaust pipes. We made a battery tray, and we can laser cut those for anyone who needs one. The motor mounts to the firewall with the standard DA50 spacers, retaining the same thrust angles. It was easier doing the electric conversion than the gas setup because there is no tank or associated plumbing, ignition stuff, etc.
Posted on: 1/13/2010 11:56 AM by Author "JimDrew" in the forum "Aero-Works Support"
http://www.rcuniverse.com/forum/fb.asp?m=9412310

RE: Aero Works P-51?
We are using 2 of our XPS Pro 6S 5000mAh packs. The weight is 23 pounds ready to fly WITH batteries. We think the plane is actually too light, so we plan to load it up with 6400mAh batteries (which fit quite easily). That would put the weight right at 25 pounds. Our TopFlight Mustang had a similar 12S 5000mAh electric setup and weighed 28 pounds, and did not have split gear doors or retractable tail wheel... it also did not fly anything like this plane. The Aeroworks version is nimble and tracks like it is on rails (as you can see from the videos).
Posted on: 1/12/2010 11:43 PM by Author "JimDrew" in the forum "Aero-Works Support"
http://www.rcuniverse.com/forum/fb.asp?m=9411330

RE: Aero Works P-51?
My company, Xtreme Power Systems, did the electric conversion of the Mustang. Not only does the electric setup sound much like a real Merlin going by, the speed difference over gas is dramatic. We are spinning the same size propeller at 9,000 RPMs, and this is a relatively mild electric setup from what it could be. This model is not only everything you ever wanted in a Mustang, it's also everything you ever wanted in a model that comes out of a box! We were so surprised when we simply plugged the gear sequencer into the retract channel on our receiver, added air, and watched the landing gear (and doors) go up and down without having to do anything more! The fit and finish is excellent. We simply can not find anything wrong with the model. The electric conversion offers these advantages: Lighter setup... same weight at the gas version (without fuel). No change in CG... there is no fuel to burn. Faster acceleration, higher top speed. Motor never dies in flight. No tuning required for altitude changes. Easily rips the prop! Sounds like a Merlin and not a chainsaw engine. :) Thanks to Rocco and the rest of the Aeroworks crew for the great time we had at the AMA Expo. We look forward to doing more electric conversions of the great aircraft that Aeroworks produces!
Posted on: 1/12/2010 8:04 PM by Author "JimDrew" in the forum "Aero-Works Support"
http://www.rcuniverse.com/forum/fb.asp?m=9410776

RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
Tom, if you mounted a thin (.031") PCB the full length of the drive shaft length, you could use a simple (yet effective) trick to read the position of the shaft by measuring the capcitance/inductance of the PCB traces as a small nut (attached to the shaft) moves back and forth on the shaft. I designed a servo for our new pico series receivers that uses the same technique. It works well enough to act as a pot for a servo position control, so it will be more than adequate for this application.
Posted on: 12/13/2009 10:26 PM by Author "JimDrew" in the forum "RC Robotics and Autonomous Robots"
http://www.rcuniverse.com/forum/fb.asp?m=9328718

RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
[quote]ORIGINAL: TOMAPOWA [quote]ORIGINAL: JimDrew I think you misunderstood my intentions on timing. If you time the duration and subtract a certain amount you can use that as a reference point of where to slow down the motor to finish the remainder of the cycle. This eliminate potential damage if a bind were to occur at the end of the cycle, and this completely removes the need for spinning
Posted on: 12/10/2009 9:40 PM by Author "JimDrew" in the forum "RC Robotics and Autonomous Robots"
http://www.rcuniverse.com/forum/fb.asp?m=9320537

RE: 2.4ghz lockout today
[quote]ORIGINAL: hyperdyne Actually I believe you are incorrect. The patent states that the change-over circuit constantly monitors the incoming data. I mean, if it just did it once and chose an antenna - that would be trivial. Certainly comparing signal strengths and choosing an antenna is not worth much of a patent. If you re-read the patent, it explains how the change-over circuit monitors the correlation peak (assuming from the prompt correlator) and uses that to make a decision on which antenna to use. For those who are versed in SS, multipath fading directly effects the correlation triangle and reshapes it into something less ''pretty''. The circuit could easily monitor one (or more) correlator outputs and detect when the triangle starts going wonky. The preamble stuff is so they can make a decision and toss the packet if need be. So this algorithm was made to run in real time. If you are doing the same thing, congrats. But you are admitting that you just figured out what Futaba actually did last decade.[/quote] Correlation peak comes from the peak signal strength in the preamble. This is the main portion of the patent claim: "A receive antenna for receiving a packet is selected during a period of time for which a preamble section of the packet is received, to thereby keep change-over between packets from being carried out [b]during receiving of the packet[/b]. This eliminates a situation that a packet must be nullified due to [i]generation of a bit error by change-over between receive antennas [/i][b]during receiving of the packet[/b], to thereby keep transmission efficiency from being deteriorated even in a multipath environment." The patent has two merits, 1) that the antenna with the most peaks is the one selected for use, and 2) the antennas are never switched during the course of reading the data portion of the packet. Trust me, lots of lawyers were involved in deciphering of this one.
Posted on: 12/9/2009 12:31 PM by Author "JimDrew" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=9316514

RE: 2.4ghz lockout today
[quote]ORIGINAL: hyperdyne I was able to look at several radios today on a spec-a. I have some screen shots I need to upload. The results are interesting, particularly in the way Spektrum chooses the two frequencies to put the DSSS signals. It makes me believe there is NO Rx inside the transmitter analyzing the band. And if there is, then Spektrum can still do a terrible job in selecting the 2 freqs. I was quite surprised. [/quote] There is definitely an Rx in the Spektrum transmitters. They use the Cypress 693x transceiver chip. Incidentally, I agree with your comments on wider bandwidth usage and the spreading advantages. This is why we chose a long time proven 802.15.4 protocol, having a bandwidth of around 1.9MHz with 5MHz channel spacing. We also use CCA (collision avoidance) by checking for a busy frequency before transmission and holding off until it is free (or eventually switching to another frequency). There is also a random backoff exponent that prevents the packets from being sent at the exact same interval, every time. That with all packets being ACK'd by the receiver (with automatic retries on failure), makes our system quite resiliant to noise.
Posted on: 12/9/2009 12:22 PM by Author "JimDrew" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=9316534

RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
I think you misunderstood my intentions on timing. If you time the duration and subtract a certain amount you can use that as a reference point of where to slow down the motor to finish the remainder of the cycle. This eliminate potential damage if a bind were to occur at the end of the cycle, and this completely removes the need for spinning the motor the opposite direction to "relax" the threads. Running full tilt until the current sensor kicks in is too late, and the reason you are having to back it up right now. If this process is repeated over and over again, something is definitely wearing out quicker. Just a suggestion... :)
Posted on: 12/8/2009 5:45 PM by Author "JimDrew" in the forum "RC Robotics and Autonomous Robots"
http://www.rcuniverse.com/forum/fb.asp?m=9314521

RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
BTW, I used the 33887 in a project about 5 years ago. It gets hot. There is a reason for that big heat sink on the bottom. RDs is 120mohm, so there is quite a bit of resistance and if you don't use a larger value than recommended for the CCP, it gets really hot. What I did not like about this part (and eventually had to abandon it) is that it is 5.0v only. You can't run it on a 3.3v micro setup directly.
Posted on: 12/8/2009 12:47 AM by Author "JimDrew" in the forum "RC Robotics and Autonomous Robots"
http://www.rcuniverse.com/forum/fb.asp?m=9312864

RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
Yes, you can fit all of those parts quite easily. The PIC10F series are 6 pin SO-23-5 packages. If you use the newer PIC10F220 you can use the built-in A/D and get rid of the cap/resistor, making it even smaller. The FETs are rated 5.9A continuous (22A pulsed), plenty enough for this application. There are new integrated packages now that are even smaller with the same current capability. Using conformal coating takes care of any environmental issues. We have had this designed for a few years, but scrapped the idea of bringing it to market when I found out about the Lado gear. We have been toying around with this again, and even have samples of some actuators from Canada that have position sensing capabilities, so they could also be used for gear doors, speed brakes, etc. If you time the duration of the retract operation ("learn mode" the first time the system is powered up and used) you can then deliberately pulse the FETs towards the end of the cycle to prevent the binding. This way you don't have to back up the motor to relax the binding situation. Besides giant scale, our focus is on the 1/2A size retracts, so small and light weight is critical.
Posted on: 12/8/2009 12:37 AM by Author "JimDrew" in the forum "RC Robotics and Autonomous Robots"
http://www.rcuniverse.com/forum/fb.asp?m=9312852

RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
You could make very simple electronics for this (I did). PIC10F with a Zetex current sensor (S0-23), two dual FETs (S0-363), cap and resistor (0603). No need for A/D, yet you can measure current using this setup. You will need a voltage regulator for PIC. You could build this entire thing for dual retracts in a space of .25" x .25" if you needed to. In my case, I mounted the board directly to the motor's power wire tabs. This eliminates wires going to the motor. The PWM input is handled by the PIC so you just have a board with a servo plug. You use Y-cables to connect all the gear together to a single channel.
Posted on: 12/7/2009 11:29 PM by Author "JimDrew" in the forum "RC Robotics and Autonomous Robots"
http://www.rcuniverse.com/forum/fb.asp?m=9312709

RE: 2.4ghz lockout today
Actually, the only claim to this patent that is really relavent is checking the signal strength between two (or more) antennas during the "preamble" phase of the packet data. The preamble is the data at the start of a packet that is used to syncronize the correlator circuitry for the spread spectrum separation. The patent states that once the best antenna is selected, the antenna is never switched during the course of the reception. Perhaps in 1997 this was a good idea with hardware available at the time. However, with today's electronics that switch in nanaseconds, it is possible to switch between antennas in real time to monitor signal strength changes and switch antennas for the optimal signal strength. Our new hardware does just that.
Posted on: 12/7/2009 11:13 PM by Author "JimDrew" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=9312664

RE: 2.4ghz lockout today
Because of 2.4GHz noise in the form of video transmissions (which use carrier waves that do not contain spread spectrum encoding) you can easily have 1/4 of the usable band wiped out with a single FPV (first person video) unit. There are 4 channels available for video transmitters, each occupying 1/4 of the 2.4GHz band. If you are flying on a fixed frequency or two fixed frequencies that are close together and a FPV unit is turned on that is operating across the same frequencies, then your system can lock out. If you do frequency hopping, channel shifting, or whatever you want to call it, there is still a good chance that 1/4 of the data you are transmitting will never reach the aircraft. Fortunately, you would never know the problem was occurring due to fast frame rates and the fact that we can fly our aircraft on about 30% packet success before you start seeing it. What happens to the packet success if there are several FPV systems turned on (not far fetched in the world of R/C nowdays)? Besides having full time hopping, our system also has an adaptive mode selectable. Because our system is truly bi-directional (the receiver ACKnowegdeS the transmitter data), we can filter out channels that are not usabe, altering the hopping algorithm in real time to avoid cluttered frequencies. The frequencies are periodically checked and put back into the table if they are usable. The end result is a much higher level of successful packets getting through by avoiding the FPV systems completely.
Posted on: 12/7/2009 6:04 PM by Author "JimDrew" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=9311694

RE: JR Spectrum Failure for Jet use.
Let me chime in on one aspect that is wrong in this thread. "Liquid" does not interfere with 2.4GHz. "Water" does interfere with 2.4GHz signals, but no type of fuel (gasoline, diesel, kero, alcohol, etc.) will interfere.
Posted on: 12/7/2009 5:47 PM by Author "JimDrew" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=9311636

RE: 2.4ghz lockout today
Frequency hopping DSSS. :) I did add more text to my last post.
Posted on: 12/6/2009 4:55 PM by Author "JimDrew" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=9308595

RE: 2.4ghz lockout today
Futaba has been in the 2.4GHz market since the mid 90's. They have manufactured 2.4GHz systems for thier industrial equipment, and the patent they have covered their systems used back then, and of course now with the R/C products. Our new hardware has diversity, and gets around the patent by always switching the antennas, even while receiving the packet data. The switch occurs so quickly (every 2us), that it simulates having two antennas full time instead of just two single antennas being selected individually. Spreading protocol is based on 802.15.4, with a bandwidth of about 1.9Mhz.
Posted on: 12/6/2009 4:46 PM by Author "JimDrew" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=9308568

RE: 2.4ghz lockout today
Edited....
Posted on: 12/6/2009 4:29 PM by Author "JimDrew" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=9308515

RE: 2.4ghz lockout today
[quote]ORIGINAL: BaldEagel Talk to anyone who had the early XPS system (IFS in Europe) the system was fundermentaly incapable of doing what it was supposed to i.e. hop frequencies when experiencing interferance, but hundreds of people had succesful flights with it until the enivitable happened, normally at a differnt site, the early system has now been redesigned and is totaly different to the original, what has this to do with Spektrum you may ask, well think about it, Spektrum was brought to the market with a design flaw, this flaw has not been designed out, it has been modified so it does not last as long???????????????????????????? I will not trust my expensive airframes to this equipment, only those that are expendable. Before you jump all over me, read the first two sentences again. Mike [/quote] We didn't "redesign" anything. We didn't change anything except for some of the firmware code. The biggest change to the newer firmware was the addition of a low voltage warning. 8 out of 10 customers who upgraded to the newer firmware, reported the warning while the plane was on the bench! Each of our receivers has 3 computers inside. Computers require constant power, unlike 35MHz/72MHz which will run on fractions of a volt.
Posted on: 12/6/2009 12:41 PM by Author "JimDrew" in the forum "RC Jets"
http://www.rcuniverse.com/forum/fb.asp?m=9308042