Mixing Computer Radios for Steering- Vector and Traditional

[Stu :)]

I've got two computer transmitters (Futaba 6EXA and a Hitec Eclipse 7) and it's time to start exploiting all those nifty functions.

I'm wondering is it possible to 'mix' traditional rudder steering with vector based steering using two separate drive motors?
It would pan out like this- one channel for the rudder and a channel for each motor; a total of three channels in use. The idea being when the model is traveling straight while pushing the throttle stick forward and you moved the rudder stick to turn the model, the prop on the inside of the turn would either slow down/stop/reverse and the outside motor may either remain constant or increase.

Possible? Yes/No :confused: If 'Yes'... how???

The plan is to use it for a 1/350 battleship and maybe in the future Lindberg Fletcher "take two" project, as two previous 1/350th builds of mine and talking to others who have converted 1/350 kits, we've all suffered from the most horrid turning circles. Yet I've seen cheap-ish RTRs of similar size using vector based steering that seem to magically spin on the spot :eek:

Also of note, as 1/350th battleships don't need powerful motors, even less if your using one motor direct-drive per shaft/prop; so I'll be using 180 or equivalent sized motors and being low power motors I'll be using a servo circuits as my ESCs.

Many thanks,

Stu :)

[AndyKunz]

I have a Hitec Eclipse 7 and yes, it is possible.

I think the exact set up you want is:

Set throttle to 90% EPA, set it to be throttle + 100% of rudder. Set rudder EPA to 50% or so, then mix in throttle at 100%. You adjust the amount of mix by changing the EPA of each. The radio will take care of the > 100% for you.

It's fun to play around with these radios. They can do a lot more than the manual suggests, but you have to think outside the box a little to get it to happen.

Andy

[CaptLee]

Stu Like yourself I have been studying how to mix throttles on a computer radio, have a Polk's Tracker II and do not have it figured out yet. Am using the Dual Rate for the rudder on my single screw and it helps a bit in the smooth running out at sea, and still works great in the harbor manuevers. Have got the mixing working to trim some rudder at full speed to eliminate the torque drift, seems to help there a bit. Will follow this thread so can quit using my mixer to solve the problem on twin screw units.

[Shaun Hendricks]

You guys using the ground channels module in your Eclipse 7's? I have one as my air radio and have toyed around with the idea of ordering the module in the ground frequecies but HiTec says this is a no-no on their website and voids the warranty.

[mfr02]

If using the servo electronics as ESCs I would use the servo motors. They are already paid for when you bought the servo, and you can be sure that they are within the capacity of the servo card output stages.

[AndyKunz]

You guys using the ground channels module in your Eclipse 7's? I have one as my air radio and have toyed around with the idea of ordering the module in the ground frequecies but HiTec says this is a no-no on their website and voids the warranty.

I don't see that warranty voiding on the site (got a link to it?), but it would probably only be a protection from liability.

I use a Spectra module for planes and a Channel 75 module for surface with the same transmitter body. It's not an issue for wide/narrow issues either - both are well within spec.

The Spectra just gobbles the electrons. That's the only downside of it.

Andy

[Kmot]

Andy, maybe you could install one of those regulators like in the Spektrum (Dimension Engineering) and decrease your electron consumption time two or three fold.

[AndyKunz]

Tom,

I'll trade you a Hitec-compatible Spektrum module for a couple boxes of batteries (more are coming) and Sermos connectors ;)

Andy

[Shaun Hendricks]

I don't see that warranty voiding on the site (got a link to it?), but it would probably only be a protection from liability.

I use a Spectra module for planes and a Channel 75 module for surface with the same transmitter body. It's not an issue for wide/narrow issues either - both are well within spec.

The Spectra just gobbles the electrons. That's the only downside of it.

Andy

You're right, it's not there anymore, but I also asked them this in an email when I asked them why they didn't offer the surface module as an accessory for the Eclipse 7. I'll see if I can find that email, but they said the surface one wasn't for the Eclipse, and even though it fits, it would void the warranty.

[Ghost 2501]

right, the 6exa, if you want to use mixing on-board, you need to have the motors on the right stick, (pitch/roll) stick, then select "ELEVON" mixing, then put the rudder on channel 4, using P-mix, slave the rudder channel to the roll axis channel, off hand I cant remember which one that is on the right-hand stick. this will then give you mixing control and rudder input. its what I have done with my Yamato.

[Kmot]

I don't think there is a Spektrum module for a Hitec radio except the Lynx 3D?

But that shouldn't matter to you. I'm sure you could figure a way to get that regulator in there some how! :D

[Stu :)]

Andy- Something must be lost in translation because it did not work. Maybe I missing a step/s or something. Anyhow, you're right about how much 'more' computer radios can do, I'll properly eat these words in the future, but I'm NEVER going back to Two Channel solid state radios again. I'm really looking forward to building and driving a seven channel tug in the future.

However...

Ghost- Perfect! It worked a treat. Perhaps this is what I need to do to the Eclipse 7?

The setup for the 6EXA goes like this: The radio is physically configured for Mode 2 (left stick vertical for throttle) but electronic setup for the sticks is Mode 3. Just have to remember to not hit the Throttle Cut when out and about with the park flyer :eek:

Also found a test subject for the setup in the local toy store for 20 kiwi pesos; an Academy 1/350th Bismarck. And!... it comes with the mythological gear box and motor... which won't get used :( Typical.

Stu :)

[Shaun Hendricks]

Gobbling electrons...

I custom made a 2800mah pack for my Eclipse 7... runs for hours. Then I switch to factory while the 2800 charges. Then back to the 2800... repeat ad-naseum...

[Ghost 2501]

stu are you using 6exa (nz surface band) or 6EX (2.4ghz - multi band?),

[Stu :)]

stu are you using 6exa (nz surface band) or 6EX (2.4ghz - multi band?),

I'm using a 72MHz versions of both the 6EXA and Eclipse 7. The great thing for me is I can use cheap and light park-flier receivers for my boats.

Down here our Air/Surface rules are very different from everywhere else. The rule of thumb is basically 'first in line, first served'.
The only dedicated air frequencies in New Zealand are- 35.000 to 35.300MHz and 40.510 to 40.790MHz. 50MHz and 75MHz are illegal to use as there are used for something else. This stopped me buying a Bristol Bay a few months ago when the US$-NZ$ was good. Other than that everything else is fair game.
One current issue we are having is with certain wireless hearing aids, as they have started using 72.000 to 72.250MHz band range. We have started to complain through official channels to the government agency that governs frequency allocations, but one RC club near a retirement home who are sick of the complaints from the staff, have all but declared war.

The really big frequency issue is 2.4GHz, especially in the built up areas. Every cordless phone sold down here is 2.4GHz, a recent survey found that 3 out of 5 boardband routers are wireless (2.4GHz again), a large amount of remote security/surveillance equipment runs on 2.4GHz... it getting pretty crowded. The first time I saw a Spektrum set used, it took three attempts before the servos would actually respond to the transmitter, the other times soon as the Rx switch was flicked, everything plugged into the receiver went crazy.

Stu :)

[Stu :)]

Gobbling electrons...

I custom made a 2800mah pack for my Eclipse 7... runs for hours. Then I switch to factory while the 2800 charges. Then back to the 2800... repeat ad-naseum...

A really easy way to make a custom battery pack for your Eclipse 7 is- buy eight high amp AA batteries (I've been told not to go higher then 2500mAh) and get yourself a "Alkaline Battery Holder for Lynx/Focus SS"; Hitec part number PN-58101. Put batteries in the holder, plug holder into transmitter, charge, then you're off, no soldering, no heatshrink, no fuss. I've got two sets with 2000mAh batteries, goes and goes and goes...

It is a good idea between battery swaps to unplug the Spectra and let it cool.

Stu :)

[Ghost 2501]

so 40.925 is surface legal? yet 40.695 isnt, odd

[Stu :)]

You're are half correct. There is no 40.925 down here, but 40.930 is surface legal. Again no 40.695, but there is 40.710 and that's for model aircraft only.

http://www.nzmaa.org.nz/frequencies.asp
http://www.rsm.govt.nz/cms/licensing/types-of-licence/general-user-licences/short-range-devices/

odd

Welcome to the balmy colonies of the south Pacific....

Stu :)

[Ghost 2501]

up here in the uk, its 40.xx5 605 615 625 635 ------995 etc, why is new zealand 40.xx0?

[Stu :)]

up here in the uk, its 40.xx5 605 615 625 635 ------995 etc, why is new zealand 40.xx0?

Beats me, I just checked two LHS's websites and the only 40MHz crystals for sale are in the 20KHz steps 40.610, 630, 650, 670, 690, 710 etc etc. 72Mhz goes in 20KHz steps too.

I could find out WHY for you if you really want to know.
Are you planning on moving down here or something?

Stu :)

[Ghost 2501]

im curious thats all,