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  #1  
Old 06-09-2010, 11:04 AM
jaxrotor
 
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Thumbs up Heli setup info JR/Spektrum based part1

Generic CCPM setup, I presume -- 3 servo, 120 degree swash control.

You need to plug the three servos that move the swash into the correct channels on the RX, you need to enable 3 servo 120 degree mixing in your transmitter, then you need to get the directions set correctly for the three servos individually, and when you get THAT correct, you need to make sure the three servos work together to give you the correct movement when you move the sticks....

...Here is a step-by-step process that works every time to get your swash moving correctly:

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Enable the 120 degree, 3 servo CCPM feature in the transmitter before you do anything else.

Once you enable the CCPM feature, you should then be able to select 120 degree CCPM mixing, and the SWASH menu should be available to set the mix percentages for elevator, aileron, and pitch.

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The three servos will plug into the AILERON, ELEVATOR, and AUX 1 (PITCH) locations of your receiver.

Channel 2 is AILERON for a JR/Spektrum system
Channel 3 is ELEVATOR for a JR/Spektrum system
Channel 6 is Auxiliary 1, and also happens to be the COLLECTIVE PITCH servo channel for a JR/Spektrum System

Channel 1 is AILERON for a Futaba system
Channel 2 is ELEVATOR for a Futaba system
Channel 6 is Auxiliary 1 for a Futaba system, and also happens to be the COLLECTIVE PITCH servo channel

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Generic 120 degree CCPM swash control setup:

Whatever brand radio you use -- the receiver plugs are most likely labeled Aileron, Elevator, and AUX 1 -- the collective pitch channel.

Plug your servos into the correct channel on the RX. You have three servos controlling the swashplate. One servo connects to a ball that is either on the front or the rear of the swash and on the heli's centerline. The servo controlling this ball plugs into the ELEVATOR channel of your RX.

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The remaining two servos connect to the remaining two balls on the swash which are 120 degrees apart from the ball that is on the heli's centerline. One ball will be on the left side of the heli, the other on the right side of the heli. These connect to the AILERON channel and PITCH channel of the RX. It doesn't matter which servo plugs into which channel, as long as one goes to AILERON, the other goes to PITCH.

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Set all trim settings to zero, no trim in any direction.

Go to the SWASH mix menu, and set ELEVATOR, AILERON, and PITCH numbers to +65.

This is only a starting point, we'll fix the SIGN of the number (+/-), and the SIZE of the number (bigger/smaller) later on down the page.

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Ignore the direction of the servos for now. We're about to fix that:

Two servos in CCPM mix work to tilt the swash left and right (the servos plugged into the AILERON and PITCH channels of the RX). This is the AILERON function. The third servo (plugged into the ELEVATOR channel on the RX) must NOT move at all when you move the stick side to side.

For ELEVATOR (fore/aft) control, all three servos work to tilt the swashplate fore and aft.

For COLLECTIVE PITCH, all three servos work to move the swash up and down.

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Go to your servo reversing menu in the TX.

Move the AILERON stick to the right. The servos plugged into the AILERON and PITCH channels must move in opposite directions -- one must move UP, the other must move down. If they both move up, or both move down, reverse the direction of only ONE of them (AILERON OR PITCH) at the transmitter channel reverse menu. It doesn't matter which one at this point.

Don't worry if they don't seem to move the swash in the correct direction at this point, just make sure that they go in opposite directions when you move the stick left and right. You only need to reverse one servo, as the point here is just to get one to go up, one to go down at the same time.

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Now, move the stick for fore/aft cyclic. The servo connected to the ELEVATOR channel on the RX needs to have its direction set so that when the PITCH and AILERON servo move UP together, the ELEVATOR servo moves down (and when the ELEVATOR servo moves up, the other two move down). Use the ELEVATOR reversing function in your TX to make this happen. Don't touch the reversing for the AILERON and PITCH channels.

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At this point, the swash will tilt left and right when you move the AILERON stick, it will tilt fore and aft when you move the ELEVATOR stick, and it will move up and down (while remaining level) when you move the THROTTLE/COLLECTIVE stick.

The swash directions may be reversed at this point, but at least the servos move correctly with respect to each other.

Now to get the swash moving the right direction with respect to the stick.

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Move the AILERON to the right. The right side of the swash should tilt down. If it does, fine, move on the the elevator setting. If the AILERON control is reversed (tilts left for right stick), go the the swash mix menu and change the Aileron number from +65 to -65. Changing the SIGN of the number in the swash mix menu REVERSES the FUNCTION (in this case, Aileron).

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Move the ELEVATOR stick forward (away from you and toward the top of the transmitter). The front of the swash must tilt down. If it does, fine, don't touch anything. If the front tilts UP, reverse the ELEVATOR function by going to the swash mix menu and changing the ELEVATOR number from +65 to -65. Changing the sign of the number in the swash mix menu REVERSES the FUNCTION (in this case, ELEVATOR.

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Move the THROTTLE/COLLECTIVE stick full open (away from you, toward the top of the transmitter). You should get more positive pitch (leading edges of the blades tilt up). If the collective pitch function moves correctly, fine. If the collective pitch is backwards (you get negative pitch when you command full positive) go to the swash mix menu and change the PITCH number from +65 to -65. Changing the sign of the number in the swash mix menu REVERSES the FUNCTION (collective pitch in this case).

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Playing musical chairs with the servo reversing function at the same time you mess around with the swash mix will drive you nuts.

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With a linear 0 to 100% pitch curve, set your collective stick to its midway setting (middle). A nifty trick I learned while looking at Ron Lund's HeliProz South store is to set your pitch curve to 0-50-50-50-100 (five point curve example) so that you have a big, wide spot in the middle of the collective stick travel's range where the pitch setting will be at 50%. This makes it easy to get the zero pitch setup that comes next.

The three servo arms controlling the swash should be in the middle of their travel range. Due to the way the splines on the servo shafts are designed, you'll have to try different positions of the servo arms on the shaft to achieve this. In addition, you may also need to mess with sub trim to get the servo centered with the collective at its midpoint. The arms are either going to be horizontal or vertical, depending upon servo arrangement (unless your heli has some odd pushrod geometry).

With all trims set to neutral, all sticks at neutral, and your throttle/collective stick set to somewhere in that big flat 50-50-50 part of your pitch curve, the swash should be horizontal, and perpendicular to the MR shaft. Adjust the pushrods supporting the swashplate to make this happen.

At this setting, your blades should have ZERO pitch, the washout arms and the pitch mixing levers should be horizontal. Adjust pushrods to achieve this setting. The pushrods up on the head generally go in pairs. Make each pushrod in a pair the same length -- follow the helicopter build instructions to get the proper length of each pair of pushrods.

The swash should be in the middle of its up and down travel distance at this setting. Adjust the pushrods supporting the swashplate to achieve this setting.

So, with a linear pitch curve, at mid collective, the swash is level, the servo arms are in the middle of their travel range, the washout and pitch mixing levers are horizontal, the swash is in the middle of its travel range and the blade pitch is zero degrees (check both blades and adjust as necessary).

At this point you can select the various flight modes you are going to use and customize your pitch curve settings to match the flight mode.

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Remember -- to get the servos moving in the correct direction with respect to each other, you use the individual channel reversing menu on the transmitter.

To get the servos moving together in the proper direction with respect to the STICK, use the swash mix menu. Changing the SIGN of the number REVERSES that function.

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If you need more overall COLLECTIVE pitch travel, increase the value of the number for pitch in the swash mix menu. If you need less overall pitch travel, decrease the value of the number for PITCH in the swash mix menu.

If you need more Aileron CYCLIC pitch, increase the size of the AILERON number in the swash mix menu. If you need less Aileron CYCLIC pitch, make the AILERON number in the swash mix menu smaller.

If you need more Elevator CYCLIC pitch, increase the size of the ELEVATOR number in the swash mix menu. If you need less ELEVATOR CYCLIC pitch, then make the ELEVATOR number in the swash mix menu smaller.

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TR setup:

At neutral, and neutral trim, the servo arm for the TR is vertical, in the middle of its travel. The bellcrank at the rear is 90 degrees to the tail boom as shown in the manual.

As for the RUDDER setup, when you command a RIGHT turn (will make the NOSE of the heli turn to the right), the servo must PULL the TR pushrod forward, toward the nose of the heli.

For Left turn, the TR servo must push the TR pushrod toward the rear of the heli.
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  #2  
Old 06-09-2010, 11:05 AM
jaxrotor
 
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Thumbs up Part 2

Once you have the servo moving the correct direction, hook up the gyro. Pick up the heli and turn the nose to the LEFT while watching the TR servo arm. The gyro must command a RIGHT turn, pulling the TR pushrod forward, toward the nose. If it is backwards, and if the gyro has a reversing switch, change the direction of travel here. Go back and make sure the rudder stick still moves the servo in the correct direction.

Looking at the heli from its right side, nose to your right, tail boom to your left, the TR assembly turns COUNTER CLOCKWISE. The TR blade on the right is going UP, leading edge UP, control ball link on leading edge.

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While you're at it, here's some more in-depth reading on WHAT the SWASH mix numbers do, how to set them, and what to do with the endpoint settings and other fun stuff:

SWASH MIX and Other Fun CCPM setup notes:

The numbers in the SWASH MIX menu do nothing more than control HOW MUCH TOTAL MOVEMENT you will get for AILERON CYCLIC, ELEVATOR CYCLIC, and COLLECTIVE PITCH.

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If you were flying a standard mix, non-CCPM helicopter, if you needed more or less aileron or elevator CYCLIC movement of the swashplate, you would adjust the ENDPOINTS/ATV for the AILERON or ELEVATOR channel. If you needed more or less collective PITCH, you'd adjust the ATV/Endpoints for the collective pitch channel. If you needed to REVERSE the servo movement for one or all three of these channels, you would do the reversing in the REVERSE menu of your TX, for the channel that needed to be switched.

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But, since you have a heli whose swashplate is setup for 120 degree CCPM control, it requires that three servos work in unison to move the swashplate correctly. The individual control adjustments take on new meaning, as you have to deal with the electronic mixing that is occurring in the radio.

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The electronic mixing requires a few things to work differently in your transmitter. First, the channel reversing function in your TX ONLY affects one of the three servos, not the action of all three. The channel reversing feature in your TX ONLY allows you to get the three servos moving correctly, with respect to each other, and has nothing to do with them moving correctly with respect to the function they are controlling.

For instance, for aileron control, two servos need to move in opposite directions, one up, one down. The third servo does nothing. But if your servo reversing switches are in the wrong position, those two servos may both move up, or both move down. Fix THAT using the reverse function for ONE of the TWO servos.

Elevator requires that two servos move up (or down) in unison, while the third moves opposite (generally the elevator servo). IF all three move UP (or down), you reverse the elevator channel.

Collective requires that all three move up, or down in unison. Generally, if you get the elevator and aileron channels moving correctly with respect to each other, the collective takes care of itself.

BUT -- you may find that although the servos move correctly with respect to each other, they may move opposite of the direction required for the FUNCTION.

This is where the SWASH MIX/SWASH AFR menu comes into play. By simply changing the SIGN of the aileron, elevator, and/or pitch function, you reverse that function instead of messing with the channel reversing stuff.

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The ATV/Endpoints no longer adjust the travel of the FUNCTION, they only adjust the travel of an individual servo. So, if you find your swashplate level at mid collective/zero degrees, but that it tilts as it goes full up or full down, you use the individual endpoint/ATV settings to correct the movement of the individual servo that is moving too far, or not enough. You don't affect the other two servos in this manner.

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The SWASH MIX/SWASH AFR menu is also where you control how much total collective travel you get (full stop to stop) with the SIZE of the pitch number, and how much aileron and elevator CYCLIC pitch you get by adjusting the SIZE of the AILE and ELEV numbers in the swash mix menu.

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Finally, the numbers in the swash mix menu do NOTHING to center the swashplate in its travel range for that zero degree setting.

This is accomplished by making sure your servo arms are where they are supposed to be AT NEUTRAL (generally horizontal, parallel to the ground unless your pushrods have some weird geometry). When you have all three SERVO ARMS properly positioned at NEUTRAL (mid-stick on both sticks), you adjust the pushrods controlling the swashplate to get the swash not only level, but in the center of its overall travel range.

When you have accomplished THAT, you then adjust the pitch links up on the head generally to get all mixing arms level, and ZERO degrees pitch in BOTH blades.

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A big help in setup is to temporarily set your pitch curve to a big FLAT LINE at 50%. I picked this idea up from Ron Lund's Heliproz South website. If you have a 5-point pitch curve radio, set points 2, 3, and 4 at 50%, and point 1 at 0, point 5 at 100.

In doing so, as long as the collective stick is anywhere between points 2 and 4, the servos will be centered (neutral) and you can make your pushrods to level the swash, and center it in its overall travel range. You can set the rest of the pushrods to level the various mixing arms, and to set ZERO degrees pitch in both blades.

Finally, you can go to points 0 and/or 100 to set the overall pitch travel using the PITCH number in the SWASH MIX/AFR menu.

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To figure out what the AILE and ELEV numbers "should" be, use your pitch gauge to figure out what your cyclic pitch is.

If you turn the head so that the flybar is perpendicular to the sides of the heli (main blades -- one in front, the other over and parallel to the tail boom), set your collective stick to the ZERO degree setting, you can measure CYCLIC PITCH values for the AILERON function.

Put the pitch gauge on the MR blade sticking out front, about mid-way on the blade. MOVE THE AILERON stick side to side. Go full LEFT (or right) and measure the amount of pitch from ZERO degrees that the blade moves. Adjust the AILERON number in the SWASH MIX/AFR menu to get +/- 6 or 7 degrees of aileron cyclic.

Turn the head 90 degrees, keeping the collective at the ZERO degrees pitch setting. The flybar is now over and parallel to the tail boom, and sticking out in front, the MR blades are perpendicular to the sides of the heli.

This time, move the ELEVATOR stick to its full extreme, measuring the amount of pitch the MR blades get as you do. This time, set the ELEV number in the SWASH MIX/AFR menu to get that same +/- 6 or 7 degrees of cyclic.

If you've made it this far:

1. Your servos move correctly with respect to each other, even if you swapped the plugs at the RX for the Aileron and Pitch servos.

2. The servos move correctly with respect to the stick movements.

3. Your swash stays level from full negative pitch to full positive pitch.

4. You have adjusted your linkages to get the swash level and centered at mid stick.

5. You have zero degrees pitch in both blades at mid stick.

6. You have set the full positive and negative pitch values and know how to adjust the COLLECTIVE number in the SWASH MIX/AFR menu to increase or decrease overall travel.

7. You have set the maximum cyclic values for aileron and elevator and know how to set these using the AILE and ELEV numbers in the SWASH MIX/AFR menu.

8. You understand what the ATV/Endpoint settings do for a CCPM head and can use this to keep the swash level throughout its travel range.

9. You understand what the channel reverse settings do for a CCPM head. Next time you build a CCPM heli, you will be able to get things moving correctly in a matter of minutes.

10. You understand how to reverse the pitch, aileron, and elevator movement by changing the SIGN of the value associated with the function (AILE, ELEV, PITCH). The next time you set up a CCPM heli, you will be able to get the three functions following the stick correctly in a matter of minutes.

Go to the individual pitch curve settings and using your pitch gauge, set your normal and idle up pitch curves.

If you've gotten your gyro and tail properly set up, you're ready to go hover, track the blades, and fine-tune your pitch and throttle curves.

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If you haven't quite had enough, here's what your DX7 can do for a gyro setup:

Part 3

It tells you everything you need to know about the DX7 and gyros setup.

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This single post tells you how to set up a CCPM radio, what those numbers you're setting MEAN, and how to set up a gyro with a DX7. Can't beat that, and the price is right.

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* Making the World a Better Place -- One Helicopter at a time! *
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  #3  
Old 06-09-2010, 11:20 AM
jaxrotor
 
Posts: n/a
Thumbs up Part 3

The DX7 Gyro Sense menu. When using the Gyro Sense feature to control your gyro, you have two options to control the Gyro's gain:

1. If you select "AUTO" as shown in the picture, Gyro gain is controlled by the FLIGHT MODE SWITCH. The switch is on the top-left, front-corner of the transmitter in a heli version of the transmitter. It's a three-position switch. NORMAL mode -- the switch is positioned toward the rear of the transmitter. STNT1, the switch is centered, STNT2, the switch is toward the front of the transmitter.

STNT1 would be "Idle up 1", STNT2 would be "Idle up 2".

2. Instead of "AUTO", you can elect to use the RUDDER DUAL RATE (RUDD D/R) switch to control the gyro's gain. If you opt to use the RUDD D/R switch, JR/Spektrum refers to this as "MANUAL MODE". The RUDD D/R switch is located on the top-right, front-corner of the transmitter. (This switch normally functions as the Throttle Hold switch. If you choose to use this switch to control Gyro Gain, you'll have to reassign the Throttle hold stuff to a different switch).

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The Gyro Sense function can be user selected to use channel 7 (AUX 2 of the RX) to control the gyro's gain, or channel 5 (the GEAR channel of the RX) to control the gyro's gain. This is a cool feature if you have a six-channel receiver as it gives you more options to control your gyro instead of forcing you to use the GEAR switch and channel 5 for gain control. You can use the flexibility afforded by the Gyro Sense menu in a 6-channel RX.

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The INPUT SELECT menu is used to choose which channel -- channel 5 (GEAR), or channel 7 (AUX 2) -- will be used as the gyro gain control channel under the control of the Gyro Sense menu.



If you enter GYRO under the AUX 2 location, the Gyro Sense functions are slaved to channel 7 (AUX 2) and the gyro's gain lead MUST be plugged into channel 7 of your RX.

If you enter GYRO under the GEAR location, the Gyro Sense functions are slaved to channel 5 (GEAR) and the gyro's gain lead MUST be plugged into channel 5 of your RX.

In either case, the Flight Mode Switch (AUTO mode) or the RUDD D/R switch will control the gyro's gain, and the gains will be chosen based on the settings in the Gyro Sense menu.

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If you skip the Gyro Sense menu altogether, and simply plug the gain lead into channel 5 and use the GEAR switch, the Gear Switch controls gain, the Endpoints of the gear channel set the gain, and you get one gain for HH mode, and one gain for normal mode, as the switch only has two positions. The entry under the GEAR part of the Input Select menu MUST be set to GEAR in this case.

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Back to the Gyro Sense menu, and AUTO mode and the position of the FLIGHT mode switch.

The Flight mode switch has three positions...normal, Stunt 1, Stunt 2. On the right-hand side of the Gyro Sense Menu, you'll see

NORM:0
STNT:0

If you have THROTTLE HOLD enabled, you'll also see:

HOLD:0

on the right-hand side of the screen.

On the left-hand side, you see:

RATE:

0: 50%
1: 50%

The numbers in the RATE section select HH mode (numbers 50 to 100), and they select Normal mode (numbers 0 to 50).

If rate selections "0" and "1" are both less than 50, you can only get normal mode operation. If rate selections "0" and "1" are both greater than 50, you can only get HH mode operation.

If one of the numbers is greater than 50 and the other is less than 50, you can then set up your radio to select normal OR HH mode, depending upon the flight mode selection.

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Going back to the Right side of the screen, where you see:

NORM:0
STNT:0
HOLD:0

If you have:

RATE:

0: 75%
1: 25%

the "75%" setting will apply to the NORM, both STNT1, and STNT2 positions of the Flight Mode switch, and to throttle HOLD, when the switch is ON. That means all four flight modes would have HH mode selected.

If you have:

NORM:0
STNT:1
HOLD:0

and

RATE:

0:75%
1:25%

Then when the flight mode switch is in normal mode (towards the rear of the TX), it will select the "0:75%" setting, and HH mode.

The middle position of the switch (STNT1), and the forward STNT2 position (towards the front of the TX) will select Normal mode operation (the 1:25% setting).

HOLD, when active, will select the "0:75%" value, and HH mode.

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The "0" or "1" in the NORM/STNT/HOLD portion of the screen selects the gain value associated with the "0" and "1" values of the RATE portion of the screen.

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When using the Gyro Sense Menu, as noted above, numbers in the 50 to 100 range select HH mode, and numbers in the 0 to 50 range select normal mode operation.

If your gyro is the GY401, and you use the Gyro Sense menu, the following explains what gain is selected:



RATE 0:xx% or 1:xx% Values 50 to 100, 0 to 100% HH gain. 50% setting gives 0 gain, 75% setting gives 50% gain, 100% setting gives 100% gain.

Rate 0:xx% or 1:xx% Values 0 to 50, 100 to 0 normal mode gain. 0% setting gives 100% gain, 25% setting gives 50% gain, 50% setting gives 0% gain.

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If you elect to use RUDD D/R instead of AUTO, all of the above is still valid, except the position of the RUDD D/R switch determines the gain choice, not the Flight Mode Switch. The RATE and NORM/STNT/HOLD stuff works the same.

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If you simply decide to not use the gyro sense menu (INHibit it), use the GEAR switch and RX channel 5 for gain control, you have the following options:



GEAR channel endpoints (Travel Adjust menu) select gain.

The GEAR switch UP towards the top of the TX will select HH mode, DOWN towards the left stick will select NORMAL mode operation. (You can change that by reversing the GEAR channel in the reversing menu).

In the TRAVEL ADJ menu, under GEAR -- the first number (goes from +0 to +100) will select gain for HH mode. The second number under GEAR (goes from -0 to -100) selects gain in NORMAL mode.

For numbers 0 to 10 in either travel adjust window, the 401 will not like you. For numbers greater than 90 in either travel adjust window, the 401 will not like you. Calculating the gain:

End Points set to +/-100, anything greater than 100 is a waste of time.

+/-0 to +/-10 is no man's land. +/-91 to +/-100 is no man's land. The usable range is 10 to 90 (HH mode), and -10 to -90 (normal mode).

Based on that chart, you can set your gain as low as 11, or as high as 100%.

A setting of "10" yields gain = 11, a setting of "90" yields a gain = 100%, a setting of "45" yields a gain = 50.

In the example, the value of "72" sets the gain to 80.

You can figure out what gain the number will yield by solving the following equation:

(Desired Gain) x 0.9 = End Point Value

In the examples given in the manual:

(80) x 0.9 = 72 and (60) x 0.9 = 54

As you have found, positive numbers give you HH mode (and you need to apply power to the gyro with the switch in this position, for it to work correctly), and negative numbers give you Normal (rate) mode operation.

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Hope that helps you figure out what you really want to do with your gyro.
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  #4  
Old 06-16-2010, 12:57 PM
FORTY PERCENTER FORTY PERCENTER is offline
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Nice job, lots of work, you must sleep with your radio. I hate doing helicopter rigs (full scale)
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  #5  
Old 06-16-2010, 08:48 PM
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Motions Motions is offline
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So where did you copy and paste that from?


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  #6  
Old 06-17-2010, 05:58 AM
jaxrotor
 
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It took like 6 clicks to paste all that!! Good Info
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Old 07-22-2010, 11:16 PM
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floridaheli floridaheli is offline
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Robert,

Great write up. Learned a little that I did not know.

Thanks,
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Old 07-23-2010, 04:30 PM
r/c flyer r/c flyer is offline
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need to give me some pictures, i cant read it without picture... a pictures worth a thousend words....lol


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