Go Back  RCU Forums > RC Airplanes > RC Jets
Reload this Page >

Jeti DS-24

Notices
RC Jets Discuss RC jets in this forum plus rc turbines and ducted fan power systems

Jeti DS-24

Old 02-17-2021, 07:05 AM
  #1926  
digitech
My Feedback: (10)
 
digitech's Avatar
 
Join Date: Aug 2004
Location: klimmenlimburg, NETHERLANDS
Posts: 3,646
Received 5 Likes on 5 Posts
Default

Originally Posted by JSF-TC View Post
jvaliensi,

I feel your pain. I'm done with the CB400 also.

My Buccaneer scratch-build first flight loss has pointed a finger towards the CB400 as being partially responsible. Just like the CB200 and CB220, the CB400 has poly-fuses on each servo output and a number of people have contacted me about a history of crashes being attributed to the poly-fuse tripping and shutting down a critical servo. While the CB400 is rated for 30A continuous, each poly-fuse is only rated for 4-5A. The suspicion on the Buccaneer is that the elevator servo current draw caused the poly-fuse to blow.

Just Google 'CB400 poly fuse crash' and see what you find, especially on Flying Giants.

For my next build of the Buccaneer, I plan on using 2 CB210 boxes that don't use the poly-fuses. Distributing the 2 CB210's will also save on wiring.

Paul
i am using CBxx for years and have 0 problems , if you have a jet that uses more then 5 amps on any servo its time to eather buy better servo,s , or better building...
i use servos that pull over 35 kg each and they stall at 4 amps..
so a servo that pulls more looks to me a pretty crappy servo...
anyway its always good to blame the equipment , and not the user...
Old 02-17-2021, 07:10 AM
  #1927  
JSF-TC
My Feedback: (2)
 
JSF-TC's Avatar
 
Join Date: May 2002
Location: Fort Worth, TX
Posts: 1,174
Likes: 0
Received 38 Likes on 31 Posts
Default

I only said it was PARTLY responsible, but in retrospect, why would you put a fuse on a primary flight control - if it trips you guarantee loss of control.

See the current draw profile from telemetry below;



Nearly 9A just before impact, while most of the flight it was 1-3A. Full flaps and the deflection of the unique tailplane flap configuration likely caused an increased elevator servo draw (MKS 777A) and the inability to pull out of a steepeningdive just ma
Old 02-17-2021, 07:25 AM
  #1928  
JSF-TC
My Feedback: (2)
 
JSF-TC's Avatar
 
Join Date: May 2002
Location: Fort Worth, TX
Posts: 1,174
Likes: 0
Received 38 Likes on 31 Posts
Default

I've never had a problem with either CB200 or CB400 up until now. No issues with the CB400 in my Hawker Hunter.

I only said it was PARTLY responsible, but in retrospect, why would you put a fuse on a primary flight control - if it trips you guarantee loss of control.

See the current draw profile from telemetry below;





The servo torque was well in excess of design guidelines for the surface.

Nearly 9A just before impact, while most of the flight it was 1-3A. Full flaps and the deflection of the unique tailplane flap configuration likely caused an increased elevator servo draw (MKS 777A+ - 500oz.in/ 36kg.cm) and the inability to pull out of a steepening dive just made it worse.

Going to use a MKS X8 HBL3850 servo with over 700oz.in (50kg.cm) on the elevator for next build also.


Paul
Old 02-17-2021, 07:25 AM
  #1929  
digitech
My Feedback: (10)
 
digitech's Avatar
 
Join Date: Aug 2004
Location: klimmenlimburg, NETHERLANDS
Posts: 3,646
Received 5 Likes on 5 Posts
Default

here is a correct connected system .

Old 02-17-2021, 07:36 AM
  #1930  
jvaliensi
My Feedback: (1)
 
Join Date: Apr 2006
Location: northridge, CA
Posts: 228
Received 16 Likes on 14 Posts
Default

Shouldn't there be another jumper to the Cortex Pro? Because that is how mine was set up. Perhaps the CB220 is different?
Old 02-17-2021, 07:46 AM
  #1931  
digitech
My Feedback: (10)
 
digitech's Avatar
 
Join Date: Aug 2004
Location: klimmenlimburg, NETHERLANDS
Posts: 3,646
Received 5 Likes on 5 Posts
Default

Originally Posted by jvaliensi View Post
Shouldn't there be another jumper to the Cortex Pro? Because that is how mine was set up. Perhaps the CB220 is different?
as you can see on the labels i use clone mode and not dual path.
channel 5 of the BD is not used since i dont use mixing there..
the CB is the same as the 220 as it comes to port power..
on channel 4 on the BD you can see the cable that goes to channel 13 of the cb
the CTU and CRU are conected together onto channel 15 of the CB (e1)

Old 02-17-2021, 07:52 AM
  #1932  
Didier
 
Join Date: Dec 2002
Location: Hoofddorp, NETHERLANDS
Posts: 527
Received 13 Likes on 10 Posts
Default

Originally Posted by jvaliensi View Post
Shouldn't there be another jumper to the Cortex Pro? Because that is how mine was set up. Perhaps the CB220 is different?
It is not the same. Sandor connected port 6 of the CP to RX1 of The CB220 only as gyro/rx data. Port 5 is not used. Port 4 is connected as power Port to the CB.
Old 02-17-2021, 07:53 AM
  #1933  
jvaliensi
My Feedback: (1)
 
Join Date: Apr 2006
Location: northridge, CA
Posts: 228
Received 16 Likes on 14 Posts
Default

Thx for the clarification.
Old 02-17-2021, 08:02 AM
  #1934  
Didier
 
Join Date: Dec 2002
Location: Hoofddorp, NETHERLANDS
Posts: 527
Received 13 Likes on 10 Posts
Default

Originally Posted by JSF-TC View Post

I only said it was PARTLY responsible, but in retrospect, why would you put a fuse on a primary flight control





Paul
The reason you put fuses in a system is to protect the system for overloads or shorts.
It is commen to your car, in real airplanes, in your house etc.
If your system trips during normal ops use, then there is fundamentally something wrong.

I had a elevator servo lead shortened on my Ultra Lightning 10 years ago. This was because my thrustpipe ruptured open en melted the isolation of the servo wire. Luckily my Powerbox prevented a crash due to the fuse.


Last edited by Didier; 02-17-2021 at 08:06 AM.
Old 02-17-2021, 08:49 AM
  #1935  
JSF-TC
My Feedback: (2)
 
JSF-TC's Avatar
 
Join Date: May 2002
Location: Fort Worth, TX
Posts: 1,174
Likes: 0
Received 38 Likes on 31 Posts
Default

One key difference from a house/ car is that we can't pull over and stop to sort it out...........

We have so many single point failure cases in every one of our models we can't protect them from all scenarios.

We have dual batteries and dual Rx's that help, but in most cases we don't have dual independent servo's and linkages on every critical surface. If we do (giant scale 3D is probably the most prevalent use of multi-servo surfaces), they are rarely truly independent and are mainly for torque requirements and stability on long/ flexible surfaces, rather than for flight critical redundancy.

Setting up dual servos that don't fight each other is complicated and just having 2 servos on a surface with perfect servo matching doesn't protect from a jammed servo - see recent CARF Hawk thread for a way to decouple the servos to offer some protection.

Flying our models, especially unproven scratch-built projects is a balance of risk. Having been bitten I know how I'm revising my next build, and that is to avoid poly-fuses. Once the design is proven with actual current draw data across the full envelope I may change my mind.


Paul
Old 02-17-2021, 09:56 AM
  #1936  
F1 Rocket
 
Join Date: Nov 2006
Location: Melbourne, FL
Posts: 541
Likes: 0
Received 18 Likes on 13 Posts
Default

Originally Posted by jvaliensi View Post
I just got a response form my Digitech dealer, and they will not help me get it fixed. I tested it yesterday and it works okay, and I wanted a new cover, because in the crash it got scratched and dented.

so it goes.
Who told you this?

Danny
Old 02-17-2021, 10:02 AM
  #1937  
jvaliensi
My Feedback: (1)
 
Join Date: Apr 2006
Location: northridge, CA
Posts: 228
Received 16 Likes on 14 Posts
Default

I didn't buy it from Aeropanda.
Old 02-17-2021, 10:13 AM
  #1938  
F1 Rocket
 
Join Date: Nov 2006
Location: Melbourne, FL
Posts: 541
Likes: 0
Received 18 Likes on 13 Posts
Default

Originally Posted by jvaliensi View Post
I didn't buy it from Aeropanda.
well… You should have
We can help in anyway. I have an order being placed for some stuff and I can have a case added to it easy enough.
The following users liked this post:
Bob_B (02-17-2021)
Old 02-17-2021, 10:47 AM
  #1939  
jvaliensi
My Feedback: (1)
 
Join Date: Apr 2006
Location: northridge, CA
Posts: 228
Received 16 Likes on 14 Posts
Default

Yes, I should have.
It be nice if you can get me a new cover. Pls let me know how to proceed.
Thx
Old 02-17-2021, 11:57 PM
  #1940  
digitech
My Feedback: (10)
 
digitech's Avatar
 
Join Date: Aug 2004
Location: klimmenlimburg, NETHERLANDS
Posts: 3,646
Received 5 Likes on 5 Posts
Default

Originally Posted by JSF-TC View Post
One key difference from a house/ car is that we can't pull over and stop to sort it out...........

We have so many single point failure cases in every one of our models we can't protect them from all scenarios.

We have dual batteries and dual Rx's that help, but in most cases we don't have dual independent servo's and linkages on every critical surface. If we do (giant scale 3D is probably the most prevalent use of multi-servo surfaces), they are rarely truly independent and are mainly for torque requirements and stability on long/ flexible surfaces, rather than for flight critical redundancy.

Setting up dual servos that don't fight each other is complicated and just having 2 servos on a surface with perfect servo matching doesn't protect from a jammed servo - see recent CARF Hawk thread for a way to decouple the servos to offer some protection.

Flying our models, especially unproven scratch-built projects is a balance of risk. Having been bitten I know how I'm revising my next build, and that is to avoid poly-fuses. Once the design is proven with actual current draw data across the full envelope I may change my mind.


Paul
well i strongly disagree...
if 2 controls fight each other , a fuseless connection is not the solution but a mnechanical one is...
for the hawk there are buetifull mechanical solutions to overcome mismatch.
anyway if you want to stay fuseless its your choice...
i made a nice video on youtube testing a CB210 fuseless ..
i tried all cables out there and found out that the cables are fuses now , until i used a AWG20 that finally burned the pin that guides your connectors.
so i guess they did manage to fuse it afterall ;-)

Old 02-18-2021, 07:35 AM
  #1941  
jackdiazccs
Junior Member
 
Join Date: Sep 2020
Posts: 15
Received 6 Likes on 6 Posts
Default

A couple of thoughts:

- Watching Jvaliensy connection diagram: had the REX3-900 been connected directly to the CB-200 instead of going via the Cortex Pro, most likely the system would have switched to 900 and the crash avoided. The REX 7 had no power after the overload; so, the situation would have been recognized by the transmitter.
Considering that both signals from the Cortex Pro to the CB-200 are internally bridged at the CP, both R1 and R2 ports were overloaded and burned. (don't know if the internal bridge has been changed, but since the receiver switching occurs at the CP, it makes sense that it is still that way).
My preference has always been to connect one receiver to the CP, and the other one directly to the Central Box. He might have belly landed and lost gyro and telemetry, but avoided the crash.

- Unless Jeti designers had a strong reason to limit the current output at R1 and R2 to 200mA, it is with no doubt the weakest link from a system reliability point of view, with catastrophic results. In fact, whichever reason they might have had is been overruled by power patching the Cortex Pro or the receivers anyway.
The only reason why there aren't more crashes because of this issue is because the overload and failure occurs mostly while at your shop
I power patch all my receivers, btw.


Jack
Old 03-26-2021, 10:59 AM
  #1942  
ZB
 
Join Date: Jul 2004
Location: , FL
Posts: 342
Likes: 0
Received 10 Likes on 10 Posts
Default

Ohhhh myyyy godnesssssss look what just showed up, fresh from the oven New Jeti DS-16 G2 Black Carbon
Happy weekend, I hope everybody will do tons of flying.

Zb/Jeti USA

Click image for larger version

Name:	Jeti DS-16 G2 1.jpg
Views:	53
Size:	1.34 MB
ID:	2270048
Click image for larger version

Name:	Jeti DS-16 G2 2.jpg
Views:	49
Size:	1.95 MB
ID:	2270049
The following users liked this post:
RickP (03-26-2021)
Old 03-26-2021, 11:15 AM
  #1943  
FrankFuss
 
Join Date: Aug 2007
Location: Littleton, CO
Posts: 189
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by ZB View Post
Ohhhh myyyy godnesssssss look what just showed up, fresh from the oven New Jeti DS-16 G2 Black Carbon
Happy weekend, I hope everybody will do tons of flying.

Zb/Jeti USA

Attachment 2270048
Attachment 2270049
Is this one anodized or painted?
Old 03-26-2021, 11:35 AM
  #1944  
ZB
 
Join Date: Jul 2004
Location: , FL
Posts: 342
Likes: 0
Received 10 Likes on 10 Posts
Default

Originally Posted by FrankFuss View Post
Is this one anodized or painted?
Anodized, paint is tricky on small edges.
Old 03-26-2021, 03:04 PM
  #1945  
camss69
My Feedback: (46)
 
camss69's Avatar
 
Join Date: Jul 2002
Location: Folsom, CA
Posts: 1,790
Received 31 Likes on 27 Posts
Default

Originally Posted by ZB View Post
Ohhhh myyyy godnesssssss look what just showed up, fresh from the oven New Jeti DS-16 G2 Black Carbon
Happy weekend, I hope everybody will do tons of flying.

Zb/Jeti USA

Attachment 2270048
Attachment 2270049
Are these shipping yet?
Also when will these be listed on the website?
Any other colors expected to arrive anytime soon?

Last edited by camss69; 03-26-2021 at 03:08 PM.
Old 03-29-2021, 08:59 AM
  #1946  
ZB
 
Join Date: Jul 2004
Location: , FL
Posts: 342
Likes: 0
Received 10 Likes on 10 Posts
Default

Originally Posted by camss69 View Post
Are these shipping yet?
Also when will these be listed on the website?
Any other colors expected to arrive anytime soon?
Black Jeti DS-16 G2 are in production, 2-3 weeks
We already have Gold/Black/Red Carbon and Black/Silver. No more colors are planned.

https://www.espritmodel.com/jeti-duplex-radio-systems-ds-16-2-4ghz-900mhz-line.aspx

Click image for larger version

Name:	Jeti DS-16 G2 1.jpg
Views:	11
Size:	1.34 MB
ID:	2270055

Zb/Jeti USA

Last edited by ZB; 03-29-2021 at 09:17 AM.
Old 03-29-2021, 09:42 AM
  #1947  
camss69
My Feedback: (46)
 
camss69's Avatar
 
Join Date: Jul 2002
Location: Folsom, CA
Posts: 1,790
Received 31 Likes on 27 Posts
Default

Originally Posted by ZB View Post
Black Jeti DS-16 G2 are in production, 2-3 weeks
We already have Gold/Black/Red Carbon and Black/Silver. No more colors are planned.

https://www.espritmodel.com/jeti-duplex-radio-systems-ds-16-2-4ghz-900mhz-line.aspx

Attachment 2270055

Zb/Jeti USA
Ok thanks!
Old 03-30-2021, 08:32 AM
  #1948  
CNeuhausel
 
Join Date: Jun 2018
Location: Summerville, SC
Posts: 1
Likes: 0
Received 0 Likes on 0 Posts
Default Jeti DS-24 Voice On Event

Folks:
Could use some help..
I believe there's a short cut button to tab through Voice on Event Screen without using the rotary dial? If yes, could you please share the process on how this is accomplished, I would greatly appreciate your assistance.
Thanks,
Craig

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 - Do Not Sell My Personal Information -

Copyright © 2021 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.