JR-9303 2.4 Field Results

[airborneSGT]

Madmax,

Thanks for the heads up; what you are saying makes sense. I think the 12x is what I will wait for. The module in my 9303 will probably be what I use for now to test out setups! Although honestly Windows is a terrible OS and its utilization of the X86 architecture is pathetic. My MAC (which is several years old) would run at the same speed as my latest PC with all the default applications.

[madmax]

Oh sweet Jeeezus! We have a mac guy among us! I have one to that I use for FCP and the video thing. Please let this be our secret.


A few more excerpts from the manual which are VERY pertinent to this conversation, and worth reading.

	Quote:
	Advanced Range Testing Using a Flight Log While the above Standard Range Testing procedure is recommended for most sport aircraft, for sophisticated aircraft that contain significant amounts of conductive/ reflective materials (i.e. turbine-powered jets, some types of scale aircraft, aircraft with carbon fuselages, etc.) the following advanced range check will confirm that all internal and remote receivers are operating optimally and that the installation (position of the receivers) is optimized for the specific aircraft. This Advanced Range Check allows the RF performance of each individual internal and remote receiver to be evaluated and to optimize the locations of each individual remote receiver. Advanced Range Testing the X9303 2.4 1. Plug a flight log (optional) into the data port in the JR R921 receiver and turn on the system (transmitter and receiver). 2. Advance the Flight Log until F- frame losses are displayed, by pressing the button on the flight log. 3. Have a helper hold your aircraft while he observes the Flight Log data. 4. Standing 30 paces away from the model, face the model with the transmitter in your normal flying position and depress and hold the bind button on the back of the transmitter. This causes reduced power output from the transmitter. 5. Have your helper position the model in various orientations (nose up, nose down, nose toward the transmitter, nose away from the transmitter, etc.) while your helper is watching the Flight Log, noting any correlation between the aircraft’s orientation and Frame Losses. Do this for 1 minute. The timer on the X9303 can be used here. For giant-scale aircraft, it’s recommended that the airplane be tipped up on its nose and rotated 360 degrees for one minute, then record the data. Next place the airplane on its wheels and do a second test, rotating the aircraft in all directions for one minute. 6. After one minute, release the bind button. A successful range check will have recorded zero frame losses. Scrolling the Flight Log through the Antenna fades (A, B, L, R) allow you to evaluate the performance of each receiver. Antenna fades should be relatively uniform. If a specific antenna is experiencing a high degree of fades, then that antenna should be moved to a different location. 7. A successful Advanced test will yield the following: H- 0 holds F- 0 frame losses A, B, R, L- Antenna fades will typically be less than 100. It’s important to compare the relative antenna fades and if a particular receiver has a significantly higher antenna fades (2 to 3X), then the test should be redone, and if the same results occur, move the offending receiver to a different location. Flight Log—Optional for JR R921 Receiver The Flight Log is compatible with JR R921 receivers. The Flight Log displays overall RF link performance as well as the individual internal and external receiver link data. Additionally it displays receiver voltage. Using the Flight Log After a flight and before turning off the receiver or transmitter, plug the Flight Log into the Data port on the JR R921 receiver. The screen will automatically display voltage i.e. 6v2= 6.2 volts. Note : When the voltage reaches 4.8 volts or less, the screen will flash indicating low voltage. Press the button to display the following information: A - Antenna fades on internal antenna A B - Antenna fades on internal antenna B L - Antenna fades on the left external antenna R - Antenna fades on the right external antenna F - Frame loss H - Holds Antenna fades—represents the loss of a bit of information on that specific antenna. Typically it’s normal to have as many as 50 to 100 antenna fades during a flight. If any single antenna experiences over 500 fades in a single flight, the antenna should be repositioned in the aircraft to optimize the RF link. Frame loss—represents simultaneous antenna fades on all attached receivers. If the RF link is performing optimally, frame losses per flight should be less that 20. A hold occurs when 45 continuous (one right after the other) frame losses occur. This takes about one second. If a hold occurs during a flight, it’s important to re-evaluate the system, moving the antennas to different locations and/or checking to be sure the transmitter and receivers are all working correctly. Note : A servo extension can be used to allow the Flight Log to more conveniently be plugged in without having to remove the aircraft’s hatch or canopy. On some models, the Flight Log can be plugged in, attached and left on the model using double-sided tape. This is common with helicopters, mounting the Flight Log conveniently to the side frame. Receiver Power System Requirements With all radio installations, it is vital that the onboard power system provides adequate power without interruption to the receiver even when the system is fully loaded (servos at maximum flight loads). This becomes especially critical with giant-scale models that utilize multiple high torque/ high current servos. Inadequate power systems that are unable to provide the necessary minimum voltage to the receiver during flight loads have become the number one cause of in-flight failures. Some of the power system components that affect the ability to properly deliver adequate power include: the selected receiver battery pack (number of cells, capacity, cell type, state of charge), switch harness, battery leads, regulator (if used), power bus (if used). While the R921 receivers’ minimum operational voltage is 3.5-volts, it is highly recommended the system be tested per the guidelines below to a minimum acceptable voltage of 4.8-volts during ground testing. This will provide head room to compensate for battery discharging or if the actual flight loads are greater than the ground test loads. Recommended Power System Guidelines 1. When setting up large or complex aircraft with multiple high torque servos, it’s highly recommended a current and voltmeter (Hangar 9 HAN172) be used. Plug the voltmeter in an open channel port in the receiver and with the system on, load the control surfaces (apply pressure with your hand) while monitoring the voltage at the receiver. The voltage should remain above 4.8 volts even when all servos are heavily loaded. Note : The optional Flight Log has a built in voltmeter and it can be used to perform this test. 2. With the current meter inline with the receiver battery lead, load the control surfaces (apply pressure with your hand) while monitoring the current. The maximum continuous recommended current for a single heavy-duty servo/battery lead is three amps while short duration current spikes of up to five amps are acceptable. Consequently, if your system draws more than three amps continuous or five amps for short durations, a single battery pack with a single switch harness plugged into the receiver for power will be inadequate. It will be necessary to use multiple packs of the same capacity with multiple switches and multiple leads plugged into the receiver. 3. If using a regulator, it’s important that the above tests are done for an extended period of 5 minutes. When current passes through a regulator, heat is generated and this heat causes the regulator to increase resistance, which in turn causes even more heat to build up (thermal runaway). While a regulator may provide adequate power for a short duration, it’s important to test its ability over time as the regulator may not be able to maintain voltage at significant power levels. 4. For really large aircraft or complex models (for example 35% and larger or jets), multiple battery packs with multiple switch harnesses are necessary or, in many cases, one of the commercially available power boxes/ busses is recommended. No matter what power systems you choose, always carry out test #1 above making sure that the receiver is constantly provided with 4.8 volts or more under all conditions. 5. The latest generation of Nickel Metal Hydride batteries incorporate a new chemistry mandated to be more environmentally friendly. These batteries, when charged with peak detection fast chargers, have tendencies to false peak (not fully charge) repeatedly. These include all brands of Ni-MH batteries. If using Ni-MH packs, be especially cautious when charging making absolutely sure that the battery is fully charged. It is recommended to use a charger that can display total charge capacity. Note the number of mAh put into a discharged pack

[madmax]

And be sure to read this section, covers everything we're talking about here:

	Quote:
	Tip on Using 2.4GHz Systems While your DSM equipped 2.4GHz system is intuitive to operate, functioning nearly identically to 72MHz systems, following are a few common questions from customers: 1. Q: Which do I turn on first, the transmitter or the receiver? A: If the receiver is turned on first, all servos except for the throttle will be driven to their preset fail-safe positions set during binding. At this time, the throttle channel doesn’t put out a pulse position preventing the arming of electronic speed controllers or, in the case of an engine-powered aircraft, the throttle servo remains in its current position. When the transmitter is then turned on, the transmitter scans the 2.4GHz band and acquires two open channels. Then the receiver that was previously bound to the transmitter scan the band and finds the GUID (Globally Unique Identifier code) stored during binding. The system then connects and operates normally. If the transmitter is turned on first, the transmitter scans the 2.4GHz band and acquires two open channels. When the receiver is then turned on for a short period (the time it takes to connect), all servos except for the throttle are driven to their preset fail-safe positions while the throttle has no output pulse; The receiver scans the 2.4GHz band looking for the previously stored GUID; and when it locates the specific GUID code and confirms uncorrupted repeatable packet information the system connects and normal operation takes place. Typically this takes 2 to 6 seconds. 2. Q: Sometimes the system takes longer to connect and sometimes it doesn’t connect at all? A: In order for the system to connect (after the receiver is bound) the receiver must receive a large number of continuous (one after the other) uninterrupted perfect packets from the transmitter in order to connect. This process is purposely critical of the environment, ensuring that it’s safe to fly when the system does connect. If the transmitter is too close to the receiver (less that 4 feet) or if the transmitter is located near metal objects (metal transmitter case, the bed of a truck, the top of a metal work bench, etc.) connection will take longer, and in some cases, connection will not occur as the system is receiving reflected 2.4GHz energy from itself and is interpreting this and unfriendly noise. Moving the system away from metal objects or moving the transmitter away from the receiver and powering the system up again will cause a connection to occur. This only happens during the initial connection. Once connected, the system is locked-in and, should a loss of signal occur (fail-safe), the system connects immediately (4ms) when signal is regained. G-26 3. Q: I’ve heard that the DSM system is less tolerant of low voltage. Is that correct? A: All DSM receivers have an operational voltage range of 3.5 to 9 volts. With most systems, this is not a problem as most servos cease to operate at around 3.8 volts. When using multiple high current draw servos with a single or inadequate battery/power source, heavy momentary loads can cause the voltage to dip below this 3.5-volt threshold, causing the entire system (servos and receiver) to brown out. When the voltage drops below the low voltage threshold (3.5 volts), the DSM receiver must reboot (go through the start-up process of scanning the band and finding the transmitter) and this can take several seconds. Please read the receiver power requirement on page G-24 as this explains how to test for and prevent this occurrence. 4. Q: Sometimes my receiver loses its bind and won’t connect, requiring rebinding. What happens if the bind is lost in flight? A: The receiver will never lose its bind unless it’s instructed to. It’s important to understand that during the binding process the receiver not only learns the GUID (code) of the transmitter but the transmitter learns and stores the type of receiver that it’s bound to. If the bind button on the transmitter is pressed at any time and the transmitter is turned on, the transmitter looks for the binding protocol signal from a receiver. If no signal is present, the transmitter no longer has the correct information to connect to a specific receiver and in essence the transmitter has been “unbound” from the receiver. We’ve had several customers that use transmitter stands or trays that unknowingly depress the bind button and the system is then turned on, losing the necessary information to allow the connection to take place. We’ve also had customers that didn’t fully understand the range test process and pushed the bind button before turning on the transmitter, also causing the system to “lose its bind.” If, when turning on, the system fails to connect, one of the following has occurred: • The wrong model has been selected in the model memory (Model Match). • The transmitter is near conductive material (transmitter case, truck bed, etc.) and the reflected 2.4GHz energy is preventing the system from connecting (see #2 above). • The bind button was unknowingly (or knowingly) depressed and the transmitter was turned on previously, causing the transmitter to no longer recognize the receiver. 5. Q: Can I use a 3-cell Li-Po pack in my transmitter A: No. All current JR and Spektrum transmitters are designed to operate using a 9.6-volt transmitter pack. A fully charged 3-cell Li-Po pack puts out 12.6 volts. This higher voltage can overload the power-regulating transistor causing damage and or failure, possibly in flight. Many of our customers have experienced failures using 3-cell Li-Po packs and their use in JR and Spektrum transmitters is highly advised against. The X9303 2.4 system will operate for over 15 hours using a 2700mAh Ni-MH battery. 6. Q: How important is it that I test my system using a flight log? A: For most sport airplanes and helicopters, the use of the flight log is unnecessary. For sophisticated aircraft, especially those that have significant conductive materials within the airframe (i.e. jets, scale airplanes, etc.), the Flight Log offers an extra measure of confidence that all radio components are working optimally. The Flight Log is an important tool that allows the confirmation that the installation (position of the internal and remote receivers relative to the conductive materials in the aircraft) is optimized and that the RF (radio) link is operating at the highest levels of performance.

[dick hanson]

[quote=madmax;297838]Mr. Hanson, I'm guilty of posting stuff sometimes when I think everyone else knows the mysterious thoughts in my head when I'm writing. My bad Hope this helps everyone who is reading.


Ask Leseberg, he re-binds many times a week.


-rebinding won't hurt -- Mark was here Saturday - but this never came up--

[Extra 1]

Today, Monday the 10th I made some changes and this is what I found.
review: Carden 260 40 % new 9303 2.4 continuing test results.
Raised JR 921...relocated / reorientation of L and R
A B L R F H
Range chk 35 0 0 0 0 0 New locations
__________________________________________________ ________
4min flt 197 339 340 301 80 0 New locations
(aggressive flying)___________________________________________ _
14 m flt 255 761 462 485 122 0 New loca. angle ex ant
(unlim fly)______________________________________________ ______
11 min flt 190 232 313 120 22 0 Orig loca. angle ex ant
(softer flying)___________________________________________ ______
Conclusion: Play around with orientation/angles/placement as they suggest.
Tim.....Not sure I like the feel any better than old system.

[GooseF22]

OMG. Mac guys amongst us? oh well......me 3..of em.

[Flyinrazrback]

I just swapped out my 9303 with the module and AR 9000 rx for the X9303 and 921. Simple swap, the only thing I was surprised at is that all my centers were off a bit than before, not sure the cause of that.

[walex]

Madmax,
Thanks for replying. I'm running 6 servos: 4 DS821's, 1 HS-645MG for rudder, 1 BMS-621MG for throttle. My battery
is 5 cell AA NiMH 2300mAh pack. I have the standard JR heavy duty on/off switch. How does that sound?

1bwana1,
I'll check out the data logger. I guess that's something that rides along in the plane?

walex

[bodywerks]

It doesn't have to. Juts run an extension out of the data port to the outside of the plane and plug the logger into it after a flight/range check and before shutting the rx off.

[Flyinrazrback]

Went out today and got 4 flights on the new X9303. Range check was flawless, and the radio worked great in the air without a hiccup. Noticeably faster than the module based version I was flying and it did feel more crisp and locked in. Impressed so far and still glad to be running 2.4

[bodywerks]

Here's my solution for keeping the main rx antenna away from any metal, electronics, or other signal absorbing media. Yes, the fuel tank is 4" in front of it, but fuel doesn't block out signals, water does - at least that is what I have read. this added a whopping 2.6 grams...

[1bwana1]

Nice idea Nick, it should help a lot. Considering that power is such a big issue with this RX, and we need to keep the antennas away from things, what we really need are power expanders designed purposely for this RX.