Upgrading transmitter / receiver to 20th century ;)

[Camano]

I'm looking for specific recommendations on how to bring my Dodgson Camano (built in 1991) into the 20th century. I want to replace the 72 MHz setup (channel 18, anyone?) with a modern transmitter and receiver. Here's my current wish list:

1. Continue to use my existing Airtronics analog servos.
2. Use a "square" battery pack for the receiver (no bigger than 4 AA cells).
3. Very good range because there are times when I may have the opportunity to safely fly at very high altitudes.
4. Telemetry: vario, battery level, signal strength
5. Easy to add more receivers (other models) in the future.

Since I have never used anything more modern than my 4-channel Airtronics transmitter from 1991, there may be other things that I don't even know about that I should add to this list -- suggestions welcome!

Some motivation / explanation for the items above:
1. The Camano has a mechanical mixer (AFART) that gives elevator / mixed rudder-aileron / flaps / trailing edge reflex (camber adjust) using just three unmixed channels and only three servos. It works like a charm, but it's complicated and I really do NOT want to try to rebuild it with new servos! (I did borrow a modern receiver and was able to confirm that these old servos did indeed work with it once I carefully convert to modern connectors.)
2. The 4-AA square pack is all that will fit.
3. No explanation needed.
4. Vario -- Besides the obvious, I think I would also enjoy being reminded of my old hang gliding days (and it would be nice to be able to program the sounds accordingly). Battery level -- I hear that digital drive to analog servos consumes significantly more power than the old analog drive did; will I be able to fly for a couple of hours on 4 AA cells? Signal strength -- Anyone who has flown long enough has had to make repairs (or get a new model) because of signal strength issues.
5. Neither DLG nor electric was really around in 1991, but they look like fun!

I'm already thinking FrSky (which is why I'm posting here); how do I decide which transmitter and receiver to get? Other info: I'm willing to pay for upgrades that I will enjoy if someone will explain them to me , I haven't ever done any contests (I know very little about it), but just joined a local club that does a lot of that stuff; I would prefer battery recharging to be straightforward (i.e., not removing battery pack).

Are there other questions I should be asking?

Thanks.

Darrell

 

[Konrad]

Dodgson was a great innovator of gliders. He really stressed the move away from polyhedral (bent wing disease). Back then in the 20th century, I too loved his mechanical mixers.

Ok, to be clear we did have a lot of high powered electric gliders. I've been flying high powered electrics since 1986 when I moved away from the 7 cell trap. The europeans had a lot of great gliders back in the late 80's and early 90's. Look up FAI F3E which later became F5B, I think they still had the 27 cell cell limit back then. I think DLG was also around in the early 90's I recall flying a DJ Aerotech Monarch back then.

To your issues (questions), your analog servos can be used in most RX application. BUT you must make sure that the refresh rate is kept down to a slow speed, something like 22 milliseconds (maybe as fast as 18 milliseconds but no faster). Most FrSky TX's allow for this slow a refresh rate. but you must select it as part of your binding process.

2.4 gHz does NOT have the range of the old 72 mHz radios. So you will want to bias all your 2.4 gHz purchases towards range. Look at some of the modern "X series" of receivers or the old L9R receivers. Also the use of the 900 mHz band might be useful. (To be honest 2.4 gHz still gives me more range than I can comfortably see a 3.5 meter glider).

FrSky Long Range

The FrSky long range system lets you go further. Want more range from your FrSky system? These long range receivers are just the ticket. Allowing twice the range, or even more. This is a great way to extend your range without breaking your bank account. No need to buy new modules, if you have a...

alofthobbies.com

Glad you are aware of the issues with the old Airtronics connector.

Power consumption is not any worse than it was in the old days, as long as you are keeping the refresh rate down and are not transmitting telemetry. You should find that with today's chemistry that 4 cell 550 mAh "AA" battery now has 4 time the energy you had in 1991. But should you move over to a modern digital servo you should see a bit of an increase in power consumption as a result of the higher refresh speeds.

Unless you have some control bind you should not see a "significant" increase in the power demands on the battery. FYI; with the mechanical mixers you might have more idle current draw than you would have with a modern radio with its programable mixes.

Now the kicker, FrSky is a great radio system with OpenTX, but it has almost nothing in common with the Master/Slave concept on mixer we have with most other brands of radios. What I'm trying to say is that there will be a learning curve trying to get the radio to do even the simplest of things, like setting up dual rates. This is much like the great radio we had in the 90's if you used or saw the Multiplex Profi 4000 mc. This really isn't an issue but be aware that it will take some effort on your part. But, once you understand the programing architecture you will find that OpenTx is a lot more freeing than the very limiting idea of master slave mixing.

I strongly recommend that you down load OpenTX Companion and practice setting up programs. There are a lot of good videos that will make this a much faster transition.

Along with the videos you can get a lot of good information from these manuals

Taranis Q X7 & X-lite OpenTX User Manual

The Taranis Q X7 Open TX 2.2 user manual is intended be a hands on, in the field or in the shop reference guide.Author, Lothar Thole has done an excellent job presenting the Taranis X7 and OpenTX in a comprehensive and concise format, rich with graphics a

alofthobbies.com

Welcome the the 21st century.

P.S.
The DJ Aerotech Monarch was still a Javelin launch but with ailerons.

 

[Camano]

Hi Konrad,

Wow, thanks for the very informative comments! I love it!

So it sounds like I was wrong about the history -- there actually were some electrics around when I started (mid-80's, northern CA), even though I don't remember seeing them. (Maybe too expensive for my group of friends? ) After I moved to semi-rural TX in 1990, I didn't see many other gliders at all for years. I definitely didn't see any DLG's in person until this century, but I guess they've been around too. One good thing about semi-rural TX in the 90's: if you wanted to fly to 3000-4000', nobody cared as long as you avoided all air traffic -- which was easy to do.

Thanks for the heads-up on the refresh rate; I will set it at 22 msec. And if 2.4 GHz is enough range for you to reach your comfort limit for a 3.5 m glider, then it should be plenty for my 2.5 m -- which I will definitely not be taking as high as I used to fly. If I went with the L9R, I would be giving up telemetry (unless I add more components, which probably won't fit). You mentioned X-series; would the G-RX6 Vario Rx be a good choice?

I've heard about the OpenTX learning curve, so I actually downloaded the OpenTX manual a couple of weeks ago and have been studying it. (As one of my friends says, "I are an inguneer," so the programming part seems like fun. But I will definitely practice with the Companion before putting my glider at risk.) And since I've never had a transmitter with any mixing at all, or even dual rates, I don't have anything to unlearn.

Am I on the right track?

Looking forward to the 21st century....

 

[jvaliensi]

I am curious; if the glider has functional mechanical mixers, and you want to keep the servos, then why do you need a OpenTX radio? It seems for this particular glider the programmable radio will not be used.

 

[Camano]

You are right -- I don't need OpenTX for this glider. Neglecting any future glider purchases for now, if all I need is telemetry (vario, battery level, signal strength), what would you suggest?

 

[Konrad]

If moving over to 2.4 gHz it would be wise to get more radio than you need. Besides OpenTX is a much more logical programing architecture than just about any other Tx program. It is also one of the less restrictive programs (read more powerful). But to some it is also more complicated.

I'm often hesitant to recommend OpenTX to raw beginners, as there is a lot to learn up front just to get the radio to work, unless they have a mentor near by. But as you know how to fly I think you would have the drive to spend a few hours to understand the basics of the radio.

There is a down loadable OpenTX manual? I hope it isn't a rip off of the fine hard copy that Aloft sells. DIYRC and Scoot Page both have some great tutorials for using OpenTX. Please be aware that there was a huge change in nomenclature awhile back that can make following these video difficult. Try to find tutorials that are based on the same firmware you have, 2.2.x. I think 2.3.x is coming out soon. Unfortunately most videos are done using 2.1.9 or earlier.

OpenTX University

A Brave New World

open-txu.org

I for one hate telemetry other than being used for signal strength. I don't like "Bitching Betty" telemetry other than during test flying of models. I like it to get in-flight data like current draw, motor and battery temperatures. But after I make sure the flight system is stable I usually kill the telemetry. I don't like varios as I tend to find myself flying the tone rather than the flying the sailplane.

Have you flown with a vario? Back in the day I too had varios. Here is a photo of my old Ace Thermic Sniffler.

I do use the G-RX6 Vario and G-RX8 Vario Rxs'. I like the G-RX8 Vario Rx a it allows me to set up 6 servo electric gliders,( 7 ch models). I do use the G-RX6 Vario Rx for my F3-RES and smaller hand launch gliders. For my larger gliders (1.8 meter plus ) try to use a second (redundant Rx) like the XM+. The G-RX6 Vario and G-RX8 Vario Rxs' allow for this redundant Rx. Please note the varios found on the G-RX6 Vario and G-RX8 Vario Rx's are not very good as altimeters. They are good at telling you the rate change but not the actual altitude.

FrSky GRX8 Vario Rx With UNI-RX

We are grateful to FrSky for entertaining our idea for a specialized glider receiver. After ?much/months? back and forth working out the design considerations, the basic plan for the G-RX8 had been laid out. The G-RX8 design features really help it to sta

alofthobbies.com

FrSky XM+ - Micro SBUS Full Range Receiver

This is the XM+. Teeny tiny and weighs just 1.5 grams. It is an excellent choice for building a micro quad. The XM can be soldered into your flight controllers wiring harness or you can solder on the included header pins so that you can connect to your fl

alofthobbies.com

If you have the space I like the RX8R pro with the XM+ Rx

FrSky RX8R PRO

An upgraded version based on the RX8R receiver, it has all the same features including redundancy. The Pro version has higher precision and lower latency. It’s deviation of PWM is reduced to 0.5us, and the delay of PWM output is 9ms less than that of the

alofthobbies.com

If you want a vario you could add this unit.

FrSky High Precision Vario ADV

FrSKY High Precision Vario Sensor monitors atmospheric pressure and reports altitude and changes in pressure, indicating lift for glider pilots.

alofthobbies.com

Yes, you are correct the L9R does not have telemetry, this is a plus in my book.

Most of my gliders are flying 2.4gHz but if I was to do a lot of cross country type thermal flying I'd look into using 900 mHz. There are a few, actually a lot of, FrSky radios that allow for the addition of a 900 mHz module.

All the best,
Konrad

 

[Konrad]

Back to your original question; What Tx to get?

Not sure what this module form is called, but I think it is going to be the new standard for FrSky. I don't know this but I think the JR module bay form is going away. (JR [Japan Radio] is no longer a viable radio manufacture {they went bankrupt}).

So if looking at Txs', look for ones that have this form of module bay if purchasing a new radio.

FrSky R9M Lite

Designed specifically for the X-Lite, the R9M Lite gives your X-Lite transmitter extended range, low latency and high precision.900MHz signals circumvent obstacles and propagate through the atmosphere far better than 2.4GHz. Using the 900MHz band allows for a stronger radio link when when your...

alofthobbies.com

 

[Camano]

Thanks -- a lot more great info; I really do appreciate it.

I do intend to get more radio than I need, and FrSky should fit the bill for that. As you say, I'm not a raw beginner (either at flying or programming), so OpenTX should be fine. I got the downloadable manual direct from www.open-tx.org; it's specifically for the Taranis, but I presume the high-level principles still apply. I won't worry about details until I get my own setup, but then I'll study the appropriate documentation / videos very carefully.

"Have I flown with a vario?" Only when I used to hang glide in the Sierras, where the thermals are so big that a little lag will not cause you to miss the core. I've never used one in a model, and honestly I never expect to use one routinely in RC flying; as you say, it is a distraction from actually flying the model. So why do I want one? Because on those days when the lift is plentiful and it is possible to fly as high and as far as you want, it would be nice to switch the vario on and pretend I'm back up there where I used to be. If I can make the audio sound like my hang gliding vario, all the better! Accurate altitude is not that important to me; I would much rather have a more responsive vario. (The altimeter I used to use on my hang glider came from AutoZone; it cost $12 and was probably good to about +/- 200 feet after you thumped the dial.)

Thanks for the specific receiver and vario suggestions; I will look at how much space I have inside the fuselage and see what will fit. I'll see what I can learn about the module bay options for transmitters; I was not aware that FrSky may be changing their standard.

 

[HENNY]

Hello from Australia.
Camano I have been flying using FRsky for several years now. I love the product and like some other brands the FRsky product is bullet proof. The new range of G-X6R or G-X8R with in built barometer will allow you to use the vario function, altitude indicator and with the correct small resistor interface board you will have flight pack voltage for a powered glider. The L9R does not have telemetry. Unless you plan to fly out of visual range the X series receivers have more than adequate range, just ensure the antennas are thru the fuselage on a carbon fiber model. You will also received voice alerts if you set them up for Alt, flight pack voltage and RSSI. There is tons of videos on Opentx on Youtube some just for glider setup.

I have the X10S and love it. There is so much free software out there including model images etc.
Hope you enjoy the new experience.
Henny

 

[Camano]

Hi Henny, thanks for the response. I have no intention of flying out of visual range -- I almost did that once by accident and never want it to happen again! So it sounds like the X-series receivers are what I should be looking at, especially since you and Konrad have both recommended them. Fuselage is fiberglass and wood, so I won't have to worry about carbon fiber unless I also get a glider from this century.

If you had to give up your X10S for a QX7, what would you miss the most? Since (as jvaliensi noted above) my current glider doesn't need even the full featureset of a QX7, it's hard for me to know what I might need for my hypothetical next glider -- I have no experience with all of those thingamajiggers.

Konrad, if you don't mind, same question for you as well -- any advice on how much sophistication I should be looking for in the transmitter? Even if I acquire more models, I'll probably be sticking to gliders (perhaps electric); so how much future-proofing should I invest in? And a random observation -- on the Thermic Sniffler, I'd swear the knob was identical to what was on the old Hammarlund radio receivers from the 50's and 60's.

Thanks again to everyone for the inputs.

Darrell

 

[HENNY]

Hi Darrell
The QX7 will do the job but being a mature aged flyer I did not like the QX7 really small screen and lower quality sticks. I already had a X9D+ and the X10S or even the X10 for me was the choice. The X10 series just has the best screen in the radio world.

Good hunting

Henny

 

[Konrad]

I'm recommending the new X Series RX. These are the ones with redundancy capabilities.
Stay away from the stabilized Rx's. (You might have noticed that their thread is the longest by far with all the issues they have).

The strong points for the Horus 10s is that it has diversity antennae and side sliders. I don’t like large screens as they add weight and battery drain. Yes the sticks are nicer but as you come from an entry level Airtronics the gimbals on the QX7 are more than adequate. (I do like the hall effect gimbals and have upgraded all my FrSky TX’s to use them). What I’d miss using the QX7 is the side sliders.

The QX7 is more than enough radio. Many guys are using them with their high end FAI F3F 3 meter racers.

https://alofthobbies.com/frsky-horus-x10s.html
https://alofthobbies.com/frsky-taranis-q-x7.html
https://alofthobbies.com/m7-hall-effect-gimbal.html

To enhance the user experience I really like neck straps or trays
https://alofthobbies.com/frsky-transmitter-harness.html

For the added $300 the Horus just doesn’t have the value of the QX7. But if I find a customer returned Horus 10S I’d be tempted to get it.

FYI: I fly the X9D+ and X9E radios

All the best,
Konrad

 

[Konrad]

For under $100 the X9 lite is a great deal! I like that it has the scroll roller (rather than the buttons of the X9D+) and it uses the new module configuration.

It also has the new ACCESS protocols.

Taranis X9 lite

Wow a $70 entry level TX with real performance, out of the box! While the title says "X9" I don't see in the sales page how many channels can be mapped? Are there more than 4 or 5 proportional channels? What are the switch configurations? I do like the small size, this helps a lot with the...

forum.alofthobbies.com

 

[Camano]

I'm a little nervous about the X9 lite for a few reasons -- besides the low price point, it seems to be the first to use ACCESS and also the first to ditch the standard JR module configuration for something new and not yet well-supported (at least, as far as I can tell). Since FrSky says that other radios will be upgradeable to ACCESS in the future, might it be safer to get something tried-and-true and upgrade later after the bugs are worked out?

Currently the X9E is looking interesting to me -- I fly "pinch" style and a tray design has some appeal. Any comments on X9E compared to X9D+ since you have experience with both? Does either include any sort of indication of antenna problems? (I had an antenna connection come loose inside the transmitter one time -- no idea how it happened, but it didn't end well.) I ask because FrSky lists "Antenna Status Detection" for both, but Aloft doesn't say anything about it, so maybe that's a translation thing. (I intend to buy from Aloft -- good stores need to be supported.)

Thanks again for your advice.

Darrell

 

[Konrad]

A wiseman once said: Do not be the first upon which the new is tried.

In tech new is defined as months not years. The “new" module bay is a tried design, as it has been out for over a year with the Taranis X-Lite.

FrSky Taranis X-Lite

Welcome to reality gaming. FrSky has done it again. Essentially, they have crammed the guts of a QX-7 into a game controller sized package. Many people have been asking for a smaller and lighter RC transmitter. The new generations of pilots are hiking out

alofthobbies.com

Yes, all modern FrSky TX's have RSSI warnings (signal strength).

ACCESS is a new protocol. And it will be the standard for FrSky for a while. I don’t think there will be a business case to offer an upgrade option for the older TX models. Because to get the full functionality of ACCESS I think there needs to be a hardware change.

I’m all but positive there won’t be an ACCESS upgrade for the X9D+ or the X9E.
Some discution on ACCESS;
https://forum.alofthobbies.com/index.php?threads/access-for-horus-x10s.958/#post-7620
And after post #51
https://forum.alofthobbies.com/index.php?threads/frsky-new-protocol.836/page-3

I hope an upgrade for the higher end radios will be offered, but I'm sure there will be a significant cost.

My take on the X9E
https://forum.alofthobbies.com/index.php?threads/x9e-getting-to-know-you.238/

All the best,
Konrad

 

[Camano]

I didn't realize that the X-Lite paved the way; that's very good to know, and it does change my opinion.

I know all the TX's have RSSI; but in the case of the antenna connection issue I had, the signal was adequate at close range, but not at the end of the hi-start launch. Besides RSSI, the X10S and X12S also support "antenna malfunction detection" and report SWR issues, which would have prevented that accident; but I guess those capabilities just come on the Horus radios.

Your writeup on the X9E hit all the right points for me, and I was about ready to commit, regardless of whether it ever gets ACCESS compatibility, because it sounds great for my flying style. But then you pointed out that it's not a good idea for DLG, which I hadn't thought of (I've never flown DLG, but it looks like fun). Dang -- I guess I can't have everything I want in one transmitter. And I never considered that "future-proofing" (making sure that I could use the radio for future needs as well) might require me to get a less sophisticated radio!

You are a fount of useful info!

 

[Konrad]

Standing Wave Ratio (SWR) is a way to measure how much energy is being radiated off the antenna, or more to the point how much power is not being transmitted and hence heating up the output stages of the tx. Here, I think this is measured assuming a 50ohm impedance. A poor connected antenna changes this value. I think this measurement (report) has been dropped in the later firmware. I recall at one time X9E having this SWR screen.

As to sophistication OpenTX is the key to the sophistication/programing power of the FrSky radio as far as programing flexibility. If using OpenTX what we are left when looking at TX selection, is the bells and whistles ( weight, screen size, switch/pot placement, ergonomic fit etc.).

As to DLG get another dedicated TX for DLG. You and I come from a time when the TX was expensive. Like I said I spent $1200 in 1990 dollars for the Multiplex Profi 4000mc V2 and was happy to pay it. But today with so many great TXs at the $100 price point, it is practical to own /use more than one tx. I fly 1/2 a dozen TXs!

What I like with OpenTX is that I can use the same programing logic across all these FrSky Txs.

All the best,
Konrad

 

[Konrad]

...
You are a fount of useful info!

Thank you!

But I think you can find a lot of folks that would disagree. Most of these are marking and sales folks (read forum owners and moderators). This does not seem to apply here as Wayne of Aloft Hobbies hasn't complained (well he has yet to complain to me)

All the best,
Konrad

 

[Camano]

Hey Konrad, I'm curious -- What do you use the side sliders for with a glider? Maybe camber adjustment?

The QX7S is the TX I'm thinking I will get; you said you would most miss the side sliders, but since I can't figure out what I'd use them for, I guess I won't miss them! I think I'll keep flaps on the left stick (where I've always had it) and put trailing edge reflex on a switch (I treat reflex as "all or nothing" anyway, so I'd rather put it on a switch than try to have fine control).

Here's the setup I'm considering. Any comments? Am I missing anything, or any upgrades that I should consider? I'm starting with just a glider with installed servos, and will purchase this:

• QX7S
• RX6R receiver (although I am considering the G-RX6 for better future flexibility)
• XM+ for redundancy
• FVAS-02H high-precision vario
• 4 x AAA NiMH battery pack (1000 mAh)
• Charge switch
• Maybe (or maybe later): GPS sensor

Do I need a separate sensor for RX battery voltage? It looks like that is built-in if I'm reading it correctly. And the RX will also report signal strength, right?

I wonder if the XM+ is overkill since there's not a speck of carbon fiber in this old glider -- all fiberglass and wood. But I guess it's cheap insurance.

Happy flying!

Darrell

 

[Wayne]

When I had a radio with side sliders I would occasionally have some flap control on there for hand launching - this helps avoid a tip stall on faster/heavier planes.

But on electrics that had both throttle and flaps I would use a side slider for CROW mix.

When I was flying slope gliders in So Cal I had flaps on my throttle stick and spoilers (ailerons up) on the side slider.

Now that I fly with an X7 I use a special mix for my gliders that has the flaps on the first half of the throttle stick, and the second have feeds in the brakes. Works well. If I should fly an electric that also has flaps, I will just use a 3 position switch. Has not been needed yet.