Questions and Answers If you have general RC questions or answers discuss it here.

Exponential setting on TX?

Reply

Old 07-25-2010, 08:32 AM
  #1  
topwinguk
Senior Member
Thread Starter
 
Join Date: Oct 2002
Location: Yeovil, UNITED KINGDOM
Posts: 125
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default Exponential setting on TX?

I have just purchased a Spectrum DX6i radio and am just installing it in a model. The manual is extremely detailed and explains settings very simply. However when setting up the exponential function I find that the instructions state that a positive setting gives a less sensitive movement around neutral. This is opposite to the instructions for setting up exponential on my Futaba Tx's, i.e. negative values provide less sensitivity around neutral. Anybody got an explanation? Seems a contradiction in protocols!

Tony

topwinguk is offline  
Reply With Quote
Old 07-25-2010, 09:14 AM
  #2  
da Rock
Senior Member
 
Join Date: Oct 2005
Location: Near Pfafftown NC
Posts: 11,511
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Exponential setting on TX?


ORIGINAL: topwinguk

I have just purchased a Spectrum DX6i radio and am just installing it in a model. The manual is extremely detailed and explains settings very simply. However when setting up the exponential function I find that the instructions state that a positive setting gives a less sensitive movement around neutral. This is opposite to the instructions for setting up exponential on my Futaba Tx's, i.e. negative values provide less sensitivity around neutral. Anybody got an explanation? Seems a contradiction in protocols!

Tony

Explanation? Yeah, major manufacturers don't want to do things the same way their competition does it.

You set exponential with positive values on JR/Spectrums and you set it to negative numbers on Futaba. Makes no sense, but that's how Futaba wants it and how JR wants it.

da Rock is offline  
Reply With Quote
Old 07-25-2010, 12:01 PM
  #3  
ChuckW
Senior Member
 
ChuckW's Avatar
 
Join Date: Jun 2006
Location: Clovis, CA
Posts: 5,165
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Exponential setting on TX?

I started in the hobby with Futaba then switched to Spektrum. When I switched back to Futaba, I programmed positive expo into a couple planes without thinking. Boy were those fun first flights; talk about sensitive controls. Then I remembered that the two manufacturers do it differently.
ChuckW is offline  
Reply With Quote
Old 07-25-2010, 02:16 PM
  #4  
Gray Beard
My Feedback: (-1)
 
Join Date: Apr 2003
Location: Hemderson, NV
Posts: 14,380
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Exponential setting on TX?

I didn't forget they did things differently, I just couldn't remember who did what and set up a students plane Bass Akwards, the kid landed and said it was a mite touchy!!!!!!!! I can never keep it straight so I always open my Futaba book to make sure I do it right. Guess that's why they give us instructions with the radios.
Gray Beard is offline  
Reply With Quote
Old 07-25-2010, 04:02 PM
  #5  
JohnBuckner
My Feedback: (1)
 
JohnBuckner's Avatar
 
Join Date: Dec 2001
Location: Kingman, AZ
Posts: 10,419
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Exponential setting on TX?

The bottom line is with the four majors (JR & Spectrum are the same for this purpose) is:


Airtronics and JR use positive expo for soft center.

Hitec and Futaba use use minus expo for soft center.

This is important to remember if you happen to use a mix of the two which I do with one JR, to avoid an occassional wild ride on a maiden.

John
JohnBuckner is offline  
Reply With Quote
Old 07-25-2010, 05:53 PM
  #6  
Charlie P.
 
Charlie P.'s Avatar
 
Join Date: Feb 2003
Location: Port Crane, NY
Posts: 5,088
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Exponential setting on TX?

That's why Futaba gives you that little graph. ;-)
Charlie P. is offline  
Reply With Quote
Old 07-25-2010, 11:20 PM
  #7  
JohnBuckner
My Feedback: (1)
 
JohnBuckner's Avatar
 
Join Date: Dec 2001
Location: Kingman, AZ
Posts: 10,419
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Exponential setting on TX?

I can think of an awful lot of Futaba models going back a lot of years with expo and no little graph. This is not a ford and chevy argument about features but a simple caution to those who fly with any mix of brands that it is vital to be fully aware of this opposing feature in each brand and that can get them into trouble very quickly.

John
JohnBuckner is offline  
Reply With Quote
Old 07-26-2010, 01:15 AM
  #8  
topwinguk
Senior Member
Thread Starter
 
Join Date: Oct 2002
Location: Yeovil, UNITED KINGDOM
Posts: 125
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Exponential setting on TX?

Thanks for the comments guys. Just wish manufacturers were more consistent. At my age I don't need any more things to confuse me!!. Now what was I about to do next!!

Tony
topwinguk is offline  
Reply With Quote

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service