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Old Dec 10, 2012, 08:19 AM
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Brighton UK
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Originally Posted by jbarchuk View Post
I'm working on a flour-based electric powered smoke system. Someone posted a purely passive system that used simply airspeed to create airflow to move the flour, but it worked fairly unspectacularly. I spent a couple of hours writing up why it didn't work so well, trying to rearrange things for it to work. Eventually I decided though that there really wasn't enough 'air power' to make it work and it'd be 1000x easier to add some electric power.

So I'm using two small motors, one is an air pump and one is a fan. Both brushed. (They -could- be operated off one channel and one simple switch but for this prototype I'd -prefer- to operate them off two channels and two tiny brushed ESCs. (ESC vs switch is pretty close to the same price anyway.))

Part of the reason for using dual channels and dual ESCs is that I -may- want to use LD and RD to vary the speed of the motors. It may not be necessary or even useful but I want to leave that option open.

I want to use SC to control both motors such that pos-0 leaves both motors off, pos-1 turns on one motor, and pos-2 turns on both motors.

After reading through a bunch of posts here I have two P-mixes very close to working but not quite. I've got the mixes and SC assigned such that in the P-mix screens the setup -does- say the switch is turning on the mixes correctly, but I'm having difficulty 'sending the command to the channel.'

Here's what I've got:

In Link - Function I have 'nothing' assigned to Ctrl or Trim for Aux1 and Aux2.

In Mdl - Prog Mix screen 1 I have:

1 [On/Off] Aux1 -> Aux1
2 [On/Off] Aux2 -> Aux2

In both P-mixes, screen 2, I have the SC correctly set up with OFF-ON-ON and OFF-OFF-ON, such that when I toggle the switch the ACT indicator in screen 2 and the on/off indicator in screen 1 behave correctly. That's good. (I've had enough experience setting up surfaces with triple rates to figure that out.)

But in the Servo screen I see no activity because I don't know how to assign the output of the mix to a channel -except- for the Function menu.

In both P-mix menu screen I haven't changed anything else, Linear, Link, Trim, and it may be something in there that I need. I hacked around a bit with Points and Offset but gained no new insight so changed them back to default.

-If- I assign CH 5 and CH 8 to SC in the Function menu, the Servo screen -does- react, but not as desired. Both pos-1 and pos-2 of SC turn on -both- channels, first from -100 to 0 (half speed) and then to +100 (full speed.)

I need pos-0 to leave both motors off, pos-1 to turn one motor full on, and pos-2 to keep the first motor on and also turn on the second motor.

So the Q is, if not the Function menu then where do I assign the output of the mixes to control the channels?

Thanks much for clues. 'Film at 11' if it works well enough.

There are several ways of doing this but the following method will work and it does leave you the option of being able to control the motor speeds via the rotary dials.

Start by assigning AUX1 and AUX2 in the Function Menu but do not assign controls or trims.

Create a new PMix. On screen 2/2 activate the mix but do NOT assign a switch.

Scroll to MASTER and select H/W (Hardware) and then select SC.

Scroll to SLAVE and select AUX1.

Return to PMix screen 1/2 . Scroll to the bottom left of the screen and change LINEAR to POINT. Set values 5, 4, 3 and 2 to +100. Set value 1 to -100.

Switch SC will now leave the AUX1 servo up (+100) when it is in its upper and middle positions and down (-100) when it is in its lower position.

Now create a second similar PMix. Again activate it without assigning a switch and set MASTER to SC.

Scroll to SLAVE and, this time, select AUX2.

Return to screen 1/2 where, this time, we want SC to generate -100 when it is in both its middle and lower positions. Accordingly change the mix from LINEAR to POINT and set value 5 to +100 and values 4, 3, 2, and 1 to -100.

Check with the servo monitor that everything is working correctly.

If you wish to be able to adjust the speed of the motors via LD and RD you will need two further PMixes.

Create a new PMix and, on screen 2/2, activate it and set SC as the on/off switch with settings OFF, OFF, ON.

Set MASTER to LD (via H/W) and SLAVE to AUX1.

On Screen 1/2 leave the mix on LINEAR and set both values to -100. (This counters the effect of the first mix). Set the Y OFFSET to +100.

The AUX1 channel will still be activated by switch SC but the amount of movement generated can be adjusted with LD.

Finally create another mix similar to the one above but assign the SC switch settings as OFF, ON, ON. Assign RD as the MASTER and AUX2 as the SLAVE. The screen 1/2 settings remain at -100 with Y OFFSET +100.

Hope that helps.
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Old Dec 10, 2012, 08:24 AM
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United States, FL, Pembroke Pines
Joined Aug 2008
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Quote:
Originally Posted by jbarchuk View Post
I'm working on a flour-based electric powered smoke system. Someone posted a purely passive system that used simply airspeed to create airflow to move the flour, but it worked fairly unspectacularly. I spent a couple of hours writing up why it didn't work so well, trying to rearrange things for it to work. Eventually I decided though that there really wasn't enough 'air power' to make it work and it'd be 1000x easier to add some electric power.

So I'm using two small motors, one is an air pump and one is a fan. Both brushed. (They -could- be operated off one channel and one simple switch but for this prototype I'd -prefer- to operate them off two channels and two tiny brushed ESCs. (ESC vs switch is pretty close to the same price anyway.))

Part of the reason for using dual channels and dual ESCs is that I -may- want to use LD and RD to vary the speed of the motors. It may not be necessary or even useful but I want to leave that option open.

I want to use SC to control both motors such that pos-0 leaves both motors off, pos-1 turns on one motor, and pos-2 turns on both motors.

After reading through a bunch of posts here I have two P-mixes very close to working but not quite. I've got the mixes and SC assigned such that in the P-mix screens the setup -does- say the switch is turning on the mixes correctly, but I'm having difficulty 'sending the command to the channel.'

Here's what I've got:

In Link - Function I have 'nothing' assigned to Ctrl or Trim for Aux1 and Aux2.

In Mdl - Prog Mix screen 1 I have:

1 [On/Off] Aux1 -> Aux1
2 [On/Off] Aux2 -> Aux2

In both P-mixes, screen 2, I have the SC correctly set up with OFF-ON-ON and OFF-OFF-ON, such that when I toggle the switch the ACT indicator in screen 2 and the on/off indicator in screen 1 behave correctly. That's good. (I've had enough experience setting up surfaces with triple rates to figure that out.)

But in the Servo screen I see no activity because I don't know how to assign the output of the mix to a channel -except- for the Function menu.

In both P-mix menu screen I haven't changed anything else, Linear, Link, Trim, and it may be something in there that I need. I hacked around a bit with Points and Offset but gained no new insight so changed them back to default.

-If- I assign CH 5 and CH 8 to SC in the Function menu, the Servo screen -does- react, but not as desired. Both pos-1 and pos-2 of SC turn on -both- channels, first from -100 to 0 (half speed) and then to +100 (full speed.)

I need pos-0 to leave both motors off, pos-1 to turn one motor full on, and pos-2 to keep the first motor on and also turn on the second motor.

So the Q is, if not the Function menu then where do I assign the output of the mixes to control the channels?

Thanks much for clues. 'Film at 11' if it works well enough.
I'm don't have my radio right now so I haven't tested this but I'm taking a stab in the dark see if it helps. First however, I would recommend you try this with only one function/motor/channel, once you get it to work you can then replicate it on the second one. Anyway, my suggestion is that instead of using an Aux to Aux mix set up an Aux to Vc (Virtual channel) or vice-versa mix, whichever works. What you want to try is to have the behavior of one of them stay flat (-100 or whatever) no matter the controls and then mix in (or add) the other channel when the correct switch is mixed in. One of the signals would not have a control assigned to it and thus you may be able to make it flat.

Again, I haven't tested this but hope it helps.

Regards,

- Birger
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Old Dec 10, 2012, 08:25 AM
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United States, FL, Pembroke Pines
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Quote:
Originally Posted by bdelapen View Post
I'm don't have my radio right now so I haven't tested this but I'm taking a stab in the dark see if it helps. First however, I would recommend you try this with only one function/motor/channel, once you get it to work you can then replicate it on the second one. Anyway, my suggestion is that instead of using an Aux to Aux mix set up an Aux to Vc (Virtual channel) or vice-versa mix, whichever works. What you want to try is to have the behavior of one of them stay flat (-100 or whatever) no matter the controls and then mix in (or add) the other channel when the correct switch is mixed in. One of the signals would not have a control assigned to it and thus you may be able to make it flat.

Again, I haven't tested this but hope it helps.

Regards,

- Birger
And of course, Malcolm posted while I was typing, do what he says first, he's the guru.

- Birger
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Old Dec 10, 2012, 11:00 AM
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France, PACA, Aix-en-Provence
Joined Dec 2007
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Quote:
Originally Posted by TimBle View Post
Dont look away at something else...

But you can also tuen the antenna vertical /upwards which is better than turning it downwards vertical..
Unfortunately, looking away is quite commonplace during F3J and F3K.

I never liked the vertical/upwards position, as my natural way of holding the transmitter is horizonta/slightly tilted forward, which is not favourable for the typical location of the aircraft, for this reason I always reckoned tilting it downwards gave me a mor perpendicular angle...
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Old Dec 10, 2012, 12:12 PM
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Brighton UK
Joined Dec 2010
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jbarchuk

Just a further thought. You could do this without using PMixes if both the Throttle and Motor Functions are available. Assign RD to one and LD to the other in the Function Menu. You can then set SC as required to kill the throttle via the Throttle Curve Menu and also to kill the motor via the Motor Menu.
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Old Dec 10, 2012, 03:00 PM
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South Africa, WC, Cape Town
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Originally Posted by Belginique View Post
Unfortunately, looking away is quite commonplace during F3J and F3K.

I never liked the vertical/upwards position, as my natural way of holding the transmitter is horizonta/slightly tilted forward, which is not favourable for the typical location of the aircraft, for this reason I always reckoned tilting it downwards gave me a mor perpendicular angle...
You could remove the antennae plug at the top, turn it through 180 degrees and...
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Old Dec 10, 2012, 03:52 PM
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Thousand Oaks, CA
Joined Mar 2004
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No, you can't. The antenna only goes in one way. And while it should be oriented downward for optimum reception this is not necessarily the best position for several reasons. First, if you do go out of range there will be no warning/recovery. Second, if you hold the TX up like we do when out of range you'll make it worse by pointing the null at the plane. Third, bending the antenna around every time you fly puts the cable at risk. My advice is to put the antenna sideways and leave it alone. Unless you fly with a tray, in which case you may want it pointing up to get away from the tray. I sure wish they would just build these antennas into the case/handle so we wouldn't have to deal with them.
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Old Dec 11, 2012, 12:58 AM
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Originally Posted by vespa View Post
No, you can't. The antenna only goes in one way. And while it should be oriented downward for optimum reception this is not necessarily the best position for several reasons. First, if you do go out of range there will be no warning/recovery. Second, if you hold the TX up like we do when out of range you'll make it worse by pointing the null at the plane. Third, bending the antenna around every time you fly puts the cable at risk. My advice is to put the antenna sideways and leave it alone. Unless you fly with a tray, in which case you may want it pointing up to get away from the tray. I sure wish they would just build these antennas into the case/handle so we wouldn't have to deal with them.
Good stuff, thanks Vespa. That makes sense. Yes, having a multidirectional fixed antenna would take away that issue. I have never had any issues with my antenna horizontal, even flying very far / low, so have confidence in this setup, I was just wondering whether my setup was optimal. Like you say, using it horizontally also means you dont have to twist the antenna around all the time. This is also the way it stores in my case.

Happy flying.
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Old Dec 11, 2012, 05:09 PM
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Originally Posted by rc man View Post
s-fhss is a good feature but with all those low cost frsky fasst receivers it may mot be worth selling your 8fg and getting an 14sg.

.
+ 1
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Old Dec 11, 2012, 08:18 PM
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Deep in the Heart of Texas
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Quote:
Originally Posted by vespa View Post
14SG has telemetry and works with all Futaba 2.4 receivers: cheap FHSS, old FASST, and new FASSTest. No other major differences exist but a number of minor ones do (vibrator, SDHC, etc.)
Just a note. One of the main reasons I am contemplating the 14SG is the vibrating timers. As an old timer, my hearing has gone the way of a few other things and when other aircraft are flying, or running on the ground, I can't hear my timers. I have flown a competing brand with a vibrating timer and loved it. Made me think of jumping ship... So in my case, the vibrator isn't in the 'minor' column . I'll most likely be selling my 14MZ and ordering a SG when they are released.

Later;

D.W.
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Old Dec 14, 2012, 06:56 PM
I live my life 12oz at a time
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United States, FL, Miami
Joined Nov 2011
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Question (ok, 2).

- If I have 10 up trim clicks in a 48" Edge, would you consider that negligible or is that indicative of flying with incorrect CG?

- Do you change the default trim size steps? The default is 4 and that is what I have been using...

Thanks!
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Old Dec 14, 2012, 08:09 PM
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Cg is a personal preference. There is no right or wrong per say. I like a neutral plane so l normally have to put in some elevator for level flight.
Your trim steps are another personal thing too. I haven't had the need to change from defaul
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Old Dec 15, 2012, 07:02 AM
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Sure. I am just trying to figure out if "10 clicks" is considered a lot or not to the point that it means I should change the CG.

Like you I am shooting for "neutral". Technically though, wouldn't the best practice be to move the CG back instead of the up elevator or at least some of it?

In an ideal world, if the plane was perfectly balanced and neutral almost no elevator should have been required no?

Interestingly enough all this trim was needed to be added when I switched from my DX7s/AR8000 to the 8FGS. Same setup, same plane, the only thing that was swapped is the Spektrum Rx. Unfortunately, I didn't measure how many mm 2 or 3 clicks of spektrum trim is. It could be that 3 spektrum trim clicks are the same as 10 8FGS clicks since they are smaller steps. Not sure just guessing. It is also assuming both Rx weigh the same and one didn't influence the CG more than the other.
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Old Dec 15, 2012, 12:53 PM
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The best way to know is fly the plane trim out the elevator and land, take a look to elevator surface and if is not parallel with the non moving part of the elevator you need to adjust the cg, if after so triming the elevator is now in neutral position parallel with the rest of the non moving area you need to adjust your linkage, with too much trim you will have more travel to one side than the other, the trim dont change servo neutral position , just give input to one side or another


Quote:
Originally Posted by arnav View Post
Sure. I am just trying to figure out if "10 clicks" is considered a lot or not to the point that it means I should change the CG.

Like you I am shooting for "neutral". Technically though, wouldn't the best practice be to move the CG back instead of the up elevator or at least some of it?

In an ideal world, if the plane was perfectly balanced and neutral almost no elevator should have been required no?

Interestingly enough all this trim was needed to be added when I switched from my DX7s/AR8000 to the 8FGS. Same setup, same plane, the only thing that was swapped is the Spektrum Rx. Unfortunately, I didn't measure how many mm 2 or 3 clicks of spektrum trim is. It could be that 3 spektrum trim clicks are the same as 10 8FGS clicks since they are smaller steps. Not sure just guessing. It is also assuming both Rx weigh the same and one didn't influence the CG more than the other.
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Old Dec 16, 2012, 08:04 PM
I live my life 12oz at a time
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United States, FL, Miami
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Originally Posted by DaxFX View Post
The best way to know is fly the plane trim out the elevator and land, take a look to elevator surface and if is not parallel with the non moving part of the elevator you need to adjust the cg,
Sorry, but I don't get this. If this is a brand new plane, then by default I would start with the elevator parallel to the horizontal stab (sometimes with a few clicks up for safety). That means that by definition if you make any changes in the air you will no longer be parallel....

Quote:
Originally Posted by DaxFX View Post
if after so triming the elevator is now in neutral position parallel with the rest of the non moving area you need to adjust your linkage, with too much trim you will have more travel to one side than the other, the trim dont change servo neutral position , just give input to one side or another
Or you can adjust through sub-trim...

Btw, this radio saved my Plane today (or at least an unnecessary dead stick landing). A couple stopped by while I was making adjustments after I landed and wanted to see me fly. Eager to please I completely forgot I haven't switched the old battery out. Luckily I set the second timer to go off 30 seconds after the time I usually set to land. That is, if a timer/alarm goes off 30 seconds into the flight it specifically means I forgot to switch the old battery out. It only happened once before, and today it did again, so I am happy I set it as it saved my butt...
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