doublesixes

I have been using a DX7 for almost 3 years with spectacular results. My planes range from 110 watts 3s to 50cc gas with everything in between.
About the only complaint that I have is the lack of throttle curve. A big bummer

Last week I started shopping for a new 2.4 system to add, as a backup for the Spektrum, so I initiated a through research of similar or better products.
My initial interest was the brand new JR 9503. Neat radio, with sophisticated features, including a 7 point throttle curve. It looked like the likely candidate until I found the fatal flaw, a mechanical throttle trim. I will not have it any other way than all digital trims.

I was really bummed by that discovery as staying with the JR/Spektrum camp implied total compatibility with my current investment in 2.4 receivers.

Next was the gorgeous Aurora from Hitec. Great radio, but lacking 2 must-have features: modelmatch and servosync. Thanks but no thanks Hitec.

The only remaining offerings are from Futaba. A nice line of all digital radios but none of them offer modelmatch and servosync that I'm aware of so I have to decline.

It looks like the lowly DX7 remains the handicapped champion. I just wished they had programmed it with a throttle curve function. Maybe they can provide a software update to include that? I hope it could be done.

AJsToyz

Does the DX7 SE have any of the features you are looking for ?

As far as the model match goes I'm with you, I really like it but the Aurora does not broadcast until you tell it to. This gives you the time to double check to make sure you have the correct model.

With the Aurora you could pretty much assign any servo you want to just about any thing. I just double checked and was able to assign all channels to the ailerons. There is also ailer2 so the radio still controls matching your servo's but you get more functions, flap diff, flaperons, crow of your using four wing servo's, the list goes on.

Just food for thought.

Andy

BuschBarber

My Feedback: (2)

I have been flying RC for 32 years. Ever since my first Computer radio, I have had to ensure that I chose the correct Model Memory before turning on my Tx. While Model Match is a nice feature, it would not stop me from purchasing my Tx of choice, if that Tx did not have Model Match. I do not feel it is that big of a risk.

Servo Sync would be more meaningful to me. I have owned a Futaba 9CAP and I currently own a couple of JR XP9303's; one with a Spektrum RF Module. Occasionally I have noticed a lag in one of two mixed servos, for my Dual Elevators, since the Mixed channels were far apart (2 and 8). I do not fly in competition so it has not really been an important enough issue to keep me from using these radios.

airbusdrvr

I've used the X9303 for 2 1/2 years. If you like the X9503, I would think the slider trim for the motor would be very easy to accommodate. When the throttle servo is set up properly, the throttle slider makes an easy to use kill switch for glow motors.

BuschBarber

My Feedback: (2)

I have found more of my fellow pilots prefer the Analog Throttle Trim than the Digital Throttle Trim. Since we fly turbine jets, among other types of aircraft, the Throttle Trim and Throttle Stick are both used together to shut off our Jetcat turbines. Using a radio with a Digital Throttle Trim takes far too long to shut off the engine in case of an accident.

I set up Throttle Cut to Kill Glow engines and a Fiber Optic Kill Switch to Kill Gas engines.

The Digital Trim on the Throttle ensures that the setting is right where you left it from the previous flight.

doublesixes

Well, I have crashed a glow plane once because I took off in the wrong model. I was using a Hitec Flash 5 then.
That would have not happened with Model Match though.

Digital throttle trim is a must because now because I fly 7 models, each with its own throttle trim parameters, kept in memory. I have programmed at least 2 idle conditions for 5 of those planes. That would be impossible to do with ANY of the JR radios, including the 12 channel unit.

Obviously the Aurora 9 offers the most bang for the money but it lacks Model Match, which is partially offset by that broadcast selection feature Andy is talking about. Also love that voltage telemetry thing about the receiver battery. Sexy screen, good looks, etc. As a con, I'd mention the lack of really small and light receivers for my 14 oz electric. 14 grams is really heavy.

airbusdrvr

doulblesixes, you wrote:"Digital throttle trim is a must because now because I fly 7 models, each with its own throttle trim parameters, kept in memory. I have programmed at least 2 idle conditions for 5 of those planes. That would be impossible to do with ANY of the JR radios, including the 12 channel unit. "

First of all, the X9303/9503 stores the trim settings(thottle included) for each model. Secondly, if you read the X9303/9505 manual you will find that different idle positions are available with these radios(flight modes). I've seen the discussion of this in the manual but don't use that feature as I fly glow only. However, it sounds as if you have your decision made, so go with whatever transmitter you decide.

CustomPC

Doublesixes, you need to take a look at the Airtronics SD-10G.

It has digital trims and Model Match when used with the 10 channel receivers.

The 5,6,7 & 8 channel receivers don't have the model match feature yet, but Airtronics will be releasing some sometime this year.

Don't let the price fool you. (Currently $399 with a 10 channel receiver). It is an extremely capable radio. More programable than the JR 9303/9503 and Futaba 8FG/10C.

It has been measured as having the lowest latency (ie. fastest response) of any radio available. It uses 2.4Ghz FHSS like the Futaba FASST system.

AJsToyz

I wonder if you could remove the case and heat shrink the 6 channel rx to save weight? Just throwing a few idea's out there. It would be nice for some nice park flier rx's in the near future.

I know about the analog throttle trim and the Throttle Recovery option, its ok just not for me. I would much rather just set a switch for a throttle kill, had no troubles at all with this on my 7C.

No matter what, every one has there own priority, and this will dictate the final decision. I do like the Model Match feature on the JR, and the programming a little better on Futaba then JR, but overall the Hitec works best for me.

Good luck!!

Andy

Pippin

CustomPC,
What does the price say about the SD10?

The 9503 hardly cost more, depending on the dealer. In the Japanese shops the radios cost about the same. I think the SD10 is even a bit above the JR. The SD10 is a 10ch anyway.

BuschBarber

My Feedback: (2)

Only JR/Spektrum has Model Match. No one else has this feature. It is patented.

DennisD

Only the Name "Model Match" is patented.

The Airtronics SD-10G also has this feature, but it is called "Safety Link"

It is currently only available only on their 10 channel FHSS-3 receiver, but will be available on their upcoming 7 and 8 channel FHSS-3 receivers as well.

Regards,

Dennis

BuschBarber

My Feedback: (2)

Thank you!!

I was not aware of that and had not seen it mentioned on any other threads.

doublesixes

airbusdrvr, I cannot find the information you are referring to about the 9503's ability to store different throttle trim settings.

Even the display on the radio doesn't show the throttle trim. I seriously doubt that the radio has some mechanical device that would move the slider corresponding to a particular throttle setting.

I've seen sound recording studio boards that actually use servos to move the sliders but it's not something implemented in R/C, to my knowledge.

If I'm wrong, please point out where in the manual says something about saving throttle trims for any of the 50 models the radio can store.

Thanks for the feedback.

stevenmax50

My Feedback: (1)

Can you guys enlighten me please?  What is modelmatch and servosync?  I recently bought the RDS8000.  I am still pretty much a novice so I do not foresee using many of the whistles and bells for another year or 2 or 3.  But it would be nice to know what those whistles and bells are. 

BuschBarber

My Feedback: (2)

Model Match and Servo Sync are features of JR/Spektrum 2.4 radios, but not Spektrum 2.4 RF Modules.

When you link a 2.4 Tx to a 2.4 Rx it is called Binding. The Tx sends out a Unique Signature to the Rx and once the Binding process is complete, the Rx will only accept signals from the Tx it is Bound to. The Rx remembers that Tx signature.

With Model Match, not only does the Rx remember the Tx, but it also remembers which Model Memory the Tx was set to during the Binding process. This means that if you accidentally set your Tx to the wrong Model Memory for your aircraft, the Rx will not recognize the signal until the correct Model Memory is selected.

If you are using a 2.4 radio that does not have Model Match, even though the Tx is Bound to the Rx, if you select the wrong Model Memory, by accident, the Tx will still communicate with the Rx and you could lose the aircraft. It is a nice feature, but we have been using radios without Model Match for years, both 2.4 and Non-2.4, so it is just an additional safety feature.

On one of these RCU threads, someone advised me that the Airtronics SDG10 has a similar feature to Model Match only they have their own name for it.

When you are mixing channels, in a Tx, using a Programmable Mixer or a Canned Program such as Elevons, Flapperons, etc., the two Mixed channels may not be close to one another (for instance Ch3 is mixed with Ch8). When the Tx sends a signal to Ch3 and Ch8, Ch3 receives the signal first and Ch8 receives the signal second. Sometimes, there is a noticeable Delay between when the signal reaches Ch3 and when it reaches Ch8. If this were a Dual Elevator mix, you might see one Elevator half move before the other Elevator half.

Servo Sync re-prioritizes the Channel Order, for mixed channels. With Servo Sync, Ch2 and Ch8 get the signal at the same time.

Model Match is for Safety and Servo Sync is for better control.

snuts

doublesixes, I use a idle-up mix on my 10X, 10 SX II, and my 9303 J.R.'s. With the idle (warm) adjusted so that the throtle trim is set to the center detent, this is done with the low end travel adjustment. The idle-up mix is then slaved to either the 10th ch twist knob, or the left trimmer switch, which is ussually also very close to center. And easily fine tuned before each flying session. These settings are stored with the model. Therefore my trim will start out on the center detent.
I even use this idle-up mix on my small glow airframes, usually only 2-300 rpm up. Hope this helps.
-Snuts-

Iflyglow

My Feedback: (79)

Stick with JR/Spectrum, as I feel the Model Match and servo sync rival any possible advantage that any competiter might have. I have seen quite a few Pilot's take off with the wrong model, and it can still be done with All Mighty Futaba 2.4 systems.[X(]

stevenmax50

My Feedback: (1)

BuschBarber...thanks for that very clear discription.  Much appreciated.

BuschBarber

My Feedback: (2)

stevenmax50 - Thank you!!

Pippin

It happend to one of my buddies that he took of with the wrong "Model" in the Tx. We were chating when he parked his Corsair to fly his Spitfire. Since both planes had a similar set up he did not notice the mistake during the preflight check. Only in the air...

I think, Airtronics/Safety Link and JR/Model Match are nice safety features. I do not care who introduced such great feature first. But nobody should make radios without it.

doublesixes

Gentlemen,

After much consideration came to the conclusion that I will stick to my DX7 for as long as it takes for the new JR 11X to become available.

Thanks to a colleague on these forums I was able to successfully program the radio to give me a 5 point throttle curve which was the feature I was fretting about. The caveat is that I now fly my planes (from 30% gas, several glow frames down to 8s, 4s, 3s electrics, micro planes and helis) in heli mode. It's no big deal once you get used to the unusual programming sequence. Anybody interested, let me know.
It works like a charm.

Now I have Model Match, Servo Sync, airplane & heli throttle curve, all 4 digital trims, DSM2 compatibility and an overall solid radio that never let me down since Sept 07. I can wait a few more months for that X11 bad boy, provided the US version has all 4 digital trims.