Throttle cut

[Diamond Geezer]

Hi guys

can anyone tell me why the throttle cut switch is operating the wrong way on hi tech optic 6 tx.

[Frank Skilbeck]

What's the right way?

[FlyinFlynn]

Tx switch wired or positioned backwards?

Edited March 24, 2022 by FlyinFlynn

[Denis Watkins]

A servo can be either way, so reverse the channel

Also, this only works at 50% or lower throttle

 

[Diamond Geezer]

Well Frank it’s opening the throttle instead of closing it.

[Outrunner]

Reverse it then?

[Diamond Geezer]

Outrunner

I have done that but obviously the throttle now closes when it should be open.

[Nick Cripps]

When setting up the throttle cut function, you need to set the servo throw percentage which can be positive or negative. Adjust that setting to get the servo to the position you require.

See page 27 of the manual here.

[Outrunner]

3 hours ago, Diamond Geezer said:

Outrunner

I have done that but obviously the throttle now closes when it should be open.

What I'm getting at is reverse the throttle cut function like Nick described.

[Keith Berriman]

Untill you really understand the America way with words you have to experiment  the throttle cut set up 

You will see a little chart that you need to set to the negative side and throttle setting on movement allowed so complicated to explain in words

[Manish Chandrayan]

Resurrecting an old thread.

I am facing a similar issue with my JR DSX9 (this is the DSM 2 Radio)

If the throttle servo is in normal mode, the throttle cut does what it is supposed to do. That is, override the idle and further close the throttle barrel to kill the engine. However due to orientation of throttle servo, if the servo needs to be reversed, when the throttle cut switch is operated it further opens up the throttle. In the throttle cut function menu on the Tx , there is an option to select + or - values for the throttle cut but selecting either still has the same result, that is, the throttle is opened more .

What is the best workaround (other than repositioning the servo itself) ? 

[Denis Watkins]

Oh flip Manish, I don't know if I can explain this, but will try, as you remember how we did this before computer radio.

Hopefully, you can see down the barrel of the carb, and you can see the servo arm. Now, try to use the outer hole of the throttle arm, and an outer or next 1 hole in of the servo arm.

Open your barrel to half way, and turn your servo arm to centre, and make sure your pushrod fits from throttle arm outer to at least 2nd hole from outer of your servo.

All being well, you are mechanically about the middle with both.

With the Tx switched off, put your throttle stick to the middle which is upright to the sky.

Now be prepared to observe as you switch the Tx on.

There should be very little difference between switching between the two.

Now observe the barrel is just fully open at full stick and

Slightly open at closed stick.

Use your end points to achieve correct barrel position high and tickover.

Now your throttle cut should do its job, and you can check on your Tx monitor too.

Edited May 10, 2023 by Denis Watkins

[Frank Skilbeck]

Make sure you have not accidentally reversed the stick action rather than the servo.

[Manish Chandrayan]

3 hours ago, Denis Watkins said:

Oh flip Manish, I don't know if I can explain this, but will try, as you remember how we did this before computer radio.

Hopefully, you can see down the barrel of the carb, and you can see the servo arm. Now, try to use the outer hole of the throttle arm, and an outer or next 1 hole in of the servo arm.

Open your barrel to half way, and turn your servo arm to centre, and make sure your pushrod fits from throttle arm outer to at least 2nd hole from outer of your servo.

All being well, you are mechanically about the middle with both.

With the Tx switched off, put your throttle stick to the middle which is upright to the sky.

Now be prepared to observe as you switch the Tx on.

There should be very little difference between switching between the two.

Now observe the barrel is just fully open at full stick and

Slightly open at closed stick.

Use your end points to achieve correct barrel position high and tickover.

Now your throttle cut should do its job, and you can check on your Tx monitor too.

Denis, thank you. I can cut the throttle by trimming it. i.e by using the trim button. What is eluding me is the electronic solution. There ought to be a way to do it. 

 

[Manish Chandrayan]

30 minutes ago, Frank Skilbeck said:

Make sure you have not accidentally reversed the stick action rather than the servo.

Frank thank you. Is it something that can be achieved on a DSX9? I am not aware of this function. Anyway, the throttle servo was reveresed from servo reverse function 

[Frank Skilbeck]

Manish, not sure you can do this on the DSX9, but I can on my MPX Royal Pro and Profi so thought I would suggest it.

Edited May 11, 2023 by Frank Skilbeck

[Manish Chandrayan]

Frank, I will check if I can on my Tx. 

[Engine Doctor]

Have a Look at page 21 in manual under throttle cut .

[Peter Jenkins]

Hi Manish

 

On my DSX9 I went to THRO TRIM and then selected the THRO Cut and clicked on the INH that turned it to ACT.  The scroll down to the next line and set the figure there either to + or - , that will determine the direction of travel of the throttle servo when you use the Trainer Switch to activate the function.  With my DSX9 set as -12% the throttle servo cuts the engine.  You cannot use THROT Cut and Memory TRIM together.

 

The alternative approach is to use one of the PROG Mix and mix THRO to THRO.  That can be assigned to any switch and not just the trainer switch.  Always embarrassing when handing control to a pupil to find the engine stops as well!

 

You can use the MONITOR screen to check that you have the throttle servo going in the right direction before trying the servo itself. 

 

Hope that helps

 

[Manish Chandrayan]

"On my DSX9 I went to THRO TRIM and then selected the THRO Cut and clicked on the INH that turned it to ACT.  The scroll down to the next line and set the figure there either to + or - , that will determine the direction of travel of the throttle servo when you use the Trainer Switch to activate the function.  With my DSX9 set as -12% the throttle servo cuts the engine.  You cannot use THROT Cut and Memory TRIM together."

 

Hello Peter, 

Thank you for chipping in. The method you describe above is what I normally do to set up the throttle cut. However, in the instant case because I reversed the servo the throttle cut function does not work. That is even when I set the values to + or -.  

Was too hot (and windy too) this past Sunday so gave flying a miss. Hopefully will try out the throttle to throttle mixing the coming weekend.   

[Manish Chandrayan]

On 11/05/2023 at 12:38, Frank Skilbeck said:

Manish, not sure you can do this on the DSX9, but I can on my MPX Royal Pro and Profi so thought I would suggest it.

Frank, 

Checked the Tx and oh yes!, there is this function. Never used so never knew the Tx had such a function. Thank you for that👍

That also springs an idea in my mind that I need to try out to solve the issue at hand.

Will let you (and others) know how that goes  

Edited May 16, 2023 by Manish Chandrayan

[Peter Jenkins]

32 minutes ago, Manish Chandrayan said:

Hello Peter, 

Thank you for chipping in. The method you describe above is what I normally do to set up the throttle cut. However, in the instant case because I reversed the servo the throttle cut function does not work. That is even when I set the values to + or -.  

Was too hot (and windy too) this past Sunday so gave flying a miss. Hopefully will try out the throttle to throttle mixing the coming weekend.   

Hi Manesh

 

I've just reversed my Throttle Servo and the Throttle Cut works in the correct sense without changing it.  Have you tried setting up a new model and checking the Throttle Cut function works there?  If that works then you could try copying your model to a spare memory and seeing if that works..

 

These things sometimes have a hissy fit!

[Manish Chandrayan]

17 hours ago, Peter Jenkins said:

Hi Manesh

 

I've just reversed my Throttle Servo and the Throttle Cut works in the correct sense without changing it.  Have you tried setting up a new model and checking the Throttle Cut function works there?  If that works then you could try copying your model to a spare memory and seeing if that works..

 

These things sometimes have a hissy fit!

Will do that over the weekend and see what results I have👍 

[Brian Cooper]

On 10/05/2023 at 13:07, Manish Chandrayan said:

Resurrecting an old thread.

I am facing a similar issue with my JR DSX9 (this is the DSM 2 Radio)

If the throttle servo is in normal mode, the throttle cut does what it is supposed to do. That is, override the idle and further close the throttle barrel to kill the engine. However due to orientation of throttle servo, if the servo needs to be reversed, when the throttle cut switch is operated it further opens up the throttle. In the throttle cut function menu on the Tx , there is an option to select + or - values for the throttle cut but selecting either still has the same result, that is, the throttle is opened more .

What is the best workaround (other than repositioning the servo itself) ? 

If the throttle servo direction has been reversed, try rebinding the radio. 

This should be done anyway to make the failsafe work properly but it might also affect the throttle cut function. 

[steve too]

On 10/05/2023 at 13:07, Manish Chandrayan said:

I am facing a similar issue with my JR DSX9 (this is the DSM 2 Radio)

If the throttle servo is in normal mode, the throttle cut does what it is supposed to do. That is, override the idle and further close the throttle barrel to kill the engine. However due to orientation of throttle servo, if the servo needs to be reversed, when the throttle cut switch is operated it further opens up the throttle. In the throttle cut function menu on the Tx , there is an option to select + or - values for the throttle cut but selecting either still has the same result, that is, the throttle is opened more

 

I just dug my DSX9 out of the back of the workshop and tried this with a clean memory. It works as I would expect and not how you describe. Perhaps you have a corrupted memory.