Andy Stephenson Posted February 17, 2023 Share Posted February 17, 2023 My own view is that 35MHz gear may have been vulnerable to mobile phone signals but a 2.4GHz transmitter has a very similar level, frequency and type of modulation of RF to a mobile phone signal floating around inside the case which means that in order to work reliably it must have immunity to itself. So why would a mobile phone cause a problem. 2 Quote Link to comment Share on other sites More sharing options...
Andy J Posted February 17, 2023 Author Share Posted February 17, 2023 Mike is there any connection between the NFL issue and uncontrolled servo demands which was an issue some years ago? The reason I ask is that on the first flight after I had purchased the Horus X10S which was just before they went obsolete is that I swore I had an uncontrolled elevator pitch down demand which was proceeded by a loss of telemetry warning. Luckily the model was only about 6ft from the ground on a landing approach so little damage was done. Given this issue I changed my Tx RF Sw to avoid the problem and have not had any further issues other than loss of telemetry alarms on a glider which I suspect was due to voltage drops caused by the motor being operated. Quote Link to comment Share on other sites More sharing options...
RottenRow Posted February 17, 2023 Share Posted February 17, 2023 After Mike's posting yesterday, I read through the RCGroup's thread about the suspected NFL issue (10 pages of it..) and it's clear from what was written that this is a different issue to the uncontrolled servo movement issue that was corrected with the V2 RF firmware. On that RCGroups thread, several people have carried out ground testing but not been able to replicate the issue. Very interesting to read even though I don't understand a lot about this subject. Brian. Quote Link to comment Share on other sites More sharing options...
Mike Blandford Posted February 17, 2023 Share Posted February 17, 2023 As far as I know, the NFL issue and the USM issue are not related, but the NFL issue cause is not known while the USM issue is fully understood, and is a problem in the Rx. Mike Quote Link to comment Share on other sites More sharing options...
Andy J Posted February 28, 2023 Author Share Posted February 28, 2023 Been thinking that this is not the first time this particular Rx had an uncontrolled elevator demand. Just prior to building the Playboy I built a bird of time which during an early trimming flight went into an uncontrolled loop followed by a dive. Thought at the time it was due to a sticking elevator cable, but perhaps not as sure I used both the rx and both servos in this model. Will try doing a soak test to see if I can get it to replicate the problem on the bench. Quote Link to comment Share on other sites More sharing options...
Chris Walby Posted February 28, 2023 Share Posted February 28, 2023 Might be worth checking the servos as recently I found out what causes (well I think so!) my Versa delta to just plummet to the ground. A rather long story, but in brief its met the ground around 4 or 5 times and once stuck in a tree. It did manage to eject the battery a couple of times, but once plugged back in everything worked ok all be it a bent motor shaft and plenty of one or none bladed prop hubs! Checked servos for smooth and full travel - ok Check RX range (test and flying outside of the field), crashes are either in the flying field or just outside - OK Replaced ESC in case the UBEC was dying after 4 minutes, WOT and just tootling did no produce the fault Replaced the motor while I was getting another shaft to replace the bent one Then it crashed again and its sitting on the bench...blades of the prop hub in my pocket! I just stand there stirring the sticks (as it has elevrons) contemplating whether it is worth another foamboard nose and motor mount and after a good 3 minutes....result! Does no not do it until the servos have been exercised for a good 3 minutes.... then one of them either travels to its extreme or does not move from its neutral position, but it then stays in that position for a couple of seconds and then returns to normal duty (the little toad). Can say that's the first servo I have found with that type of fault as it needs to be worked some time before it fails. If you can't find a fault would be worth splitting the components and using the RX in something else and bench testing the servos under load for a good period. Thing is if I had just left mine on test cycling I would not have spotted the fault, it was only because I was watching the elevrons moving that I saw one not follow the other. Good luck with the investigation and keep us all posted Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted February 28, 2023 Share Posted February 28, 2023 What make are the servos and are they genuine? Try disconnecting the good servo and see what the suspect one does then. Quote Link to comment Share on other sites More sharing options...
.thumb.JPG.051c5bb1d446ab8af8a2c911cbae321b.JPG)
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.