Go Back  RCU Forums > RC Airplanes > Extreme Speed Prop Planes
Reload this Page >

Just wondering, can you doppler a turbine?

Community
Search
Notices
Extreme Speed Prop Planes Discuss the need for speed with fast prop planes (Screamin Demon, Diamond Dust, Shrikes or any REAL sound breakin'''' plane)

Just wondering, can you doppler a turbine?

Thread Tools
 
Search this Thread
 
Old 09-16-2008, 03:50 PM
  #1  
LGM Graphix
Thread Starter
My Feedback: (22)
 
LGM Graphix's Avatar
 
Join Date: Apr 2003
Location: Abbotsford, BC, CANADA
Posts: 5,800
Received 59 Likes on 41 Posts
Default Just wondering, can you doppler a turbine?

Wondering how fast this pass was on my Kingcat at the Princeton rally this weekend. I know the jet has been on radar at 235mph but I think this pass was faster, not sure. Can turbines be doppler'd? The pass is at 5:44 on the video.
http://www.youtube.com/watch?v=p_WvBO4tmEc&feature=user

Jeremy
Old 09-16-2008, 04:27 PM
  #2  
z06kal
 
Join Date: Jun 2004
Location: Woodland Hills, CA
Posts: 211
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Just wondering, can you doppler a turbine?

You can dopler a turbine, but the music in this video is blaring making any dopler impossible it showed up as a bunch of noise on the spectrometer.
Old 09-16-2008, 04:47 PM
  #3  
Mike Connor
Senior Member
My Feedback: (5)
 
Mike Connor's Avatar
 
Join Date: Jan 2002
Location: Tulsa, OK
Posts: 2,025
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Just wondering, can you doppler a turbine?

I have never been able to Dobbler a turbine but I have trouble with 4 strokes too.
Old 09-16-2008, 06:02 PM
  #4  
LGM Graphix
Thread Starter
My Feedback: (22)
 
LGM Graphix's Avatar
 
Join Date: Apr 2003
Location: Abbotsford, BC, CANADA
Posts: 5,800
Received 59 Likes on 41 Posts
Default RE: Just wondering, can you doppler a turbine?

I thought the music might make it tough, oh well, just thought I'd ask thanks anyway guys
Old 09-25-2008, 02:17 AM
  #5  
nesikachad
Senior Member
 
Join Date: May 2007
Location: sturgis, SD
Posts: 102
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Just wondering, can you doppler a turbine?

Can someone explain where/how you doppler off a video?

Thanks.
Old 09-25-2008, 08:55 AM
  #6  
Mike Connor
Senior Member
My Feedback: (5)
 
Mike Connor's Avatar
 
Join Date: Jan 2002
Location: Tulsa, OK
Posts: 2,025
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Just wondering, can you doppler a turbine?


ORIGINAL: nesikachad

Can someone explain where/how you doppler off a video?

Thanks.
I use Windows sound recorder to record a 2-4 second wav file from the video.
Old 09-25-2008, 09:13 AM
  #7  
nesikachad
Senior Member
 
Join Date: May 2007
Location: sturgis, SD
Posts: 102
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Just wondering, can you doppler a turbine?

Mike,

Thanks but now I feel even dumber.

Exactly how does this work? I have no idea and middle school science class isn't booting up in my hard drive all that well.

If you could educate a dummy I'd be appreciative!
Old 09-25-2008, 09:40 AM
  #8  
liquid_TR
Senior Member
 
liquid_TR's Avatar
 
Join Date: Apr 2007
Location: ISTANBUL, TURKEY
Posts: 730
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Just wondering, can you doppler a turbine?

Open up your compatible video file in Sony SoundForge,

Resample the whole file to 44kHz

get the part you want to doppler, copy and paste it into a new file with 44kHz sampling,

resample the new part to 11kHz for the doppler software (the less samples, the easier to identify the doppler shift)

save it as .wav format, open it up in doppler software

and voila.. very accurate readings..
Old 09-25-2008, 10:16 AM
  #9  
Mike Connor
Senior Member
My Feedback: (5)
 
Mike Connor's Avatar
 
Join Date: Jan 2002
Location: Tulsa, OK
Posts: 2,025
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Just wondering, can you doppler a turbine?


ORIGINAL: nesikachad

Mike,

Exactly how does this work?
If you don't have the knowledge and software like liquid_TR you can do this.
The Windows sound recorder is under accessories, entertainment.
Place the microphone by your speaker.
While the video is playing you can record a short wav file starting it just before the aircraft reaches the camera during a close in level pass.
The recording should include the flight just before reaching the camera through just after passing the camera. Usually 2-4 seconds.
you can get the Doppler software at http://www.sprut.de/electronic/soft/scope.htm . (Goggle can translate to English)
There are several threads in this forum with info on this software.

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



Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.