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Jeti DS-12

Old 02-13-2021, 05:44 PM
  #476  
CARS II
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I thought I did, well here they are.




Last edited by CARS II; 02-13-2021 at 07:21 PM.
Old 02-14-2021, 10:14 AM
  #477  
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Originally Posted by CARS II View Post
We maiden my friend's T1 this passed weekend and this what we saw when we were performing the vibration checks, the picture shows the most significant vibration out of all 3 axis, it looks like this is the spot where the receiver picks up the most vibration and at around 90 to 100% throttle.
Hello,
300Hz is equivalent to 18,000 RPM, I'm not sure what RPM is full throttle, but it's not uncommon to see some kind of sub harmonic less than 1X rotational speed. However, you should see some strong 1X signal in the spectrum.

Ultrasound is 20K hz or roughly 1,200,000 RPM. Ultrasound and vibration are the same thing, same spectrum, different realm. Any signatures that high in frequency will be very low amplitude. I have a hard time believing it could interfere with a flight stabilization hardware. But I do not know flight stabilization hardware....

FWIW
RP
Old 02-14-2021, 01:58 PM
  #478  
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Originally Posted by RickP View Post
Hello,
300Hz is equivalent to 18,000 RPM, I'm not sure what RPM is full throttle, but it's not uncommon to see some kind of sub harmonic less than 1X rotational speed. However, you should see some strong 1X signal in the spectrum.

Ultrasound is 20K hz or roughly 1,200,000 RPM. Ultrasound and vibration are the same thing, same spectrum, different realm. Any signatures that high in frequency will be very low amplitude. I have a hard time believing it could interfere with a flight stabilization hardware. But I do not know flight stabilization hardware....

FWIW
RP
The noise of a jet engine has nothing to do with mechanical vibration of the engine so you cannot simply try to equate rpm to Hz. The noise is made by oscillations in the airflows. Have you never heard the very high pitch screeching of air at the front of a jet engine?
Old 02-14-2021, 04:05 PM
  #479  
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If noise didn’t cause vibration your ears couldn’t work
Old 02-15-2021, 11:01 AM
  #480  
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Originally Posted by HarryC View Post
The noise of a jet engine has nothing to do with mechanical vibration of the engine so you cannot simply try to equate rpm to Hz. The noise is made by oscillations in the airflows. Have you never heard the very high pitch screeching of air at the front of a jet engine?
I didn't say anything about noise. The post was about the vibration spectrum. And yes, Hz can be converted to RPM.

RP
Old 02-15-2021, 02:25 PM
  #481  
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Originally Posted by RickP View Post
I didn't say anything about noise. The post was about the vibration spectrum. And yes, Hz can be converted to RPM.

RP
The whole issue has been about noise, not mechanical vibration in the low frequencies shown in the Assist vib analyser which is aimed at airframe vibration in the frequencies caused by piston engines. Perhaps you have not read the thread, all along it has been about ultrasonic acoustic interference of MEMS gyros. The noise is caused by the airflow, not the movement of engine parts.
Old 02-23-2021, 07:11 AM
  #482  
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Jeti USA Press Release!!!

We would like to announce that February 23, 2021 the Federal Communication Commission and Industry Canada, Granted Equipment Authorization (FCC), and Certificate of Acceptance (IC) to Jeti USA (Esprit Model Inc.) for the Jeti Rsat 900NG 900MHz Receiver!!!


All USA orders will go out in next day or two, unfortunately Canada will have to wait till next week.

Please do not forget to Update your Transmitter and Rsat 900NG Receiver once you get it.

Zb/Esprit

https://www.espritmodel.com/jeti-dup...-ds-16-g2.aspx

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