Basil Posted March 6 Share Posted March 6 Hello, up until fairly recently I have been using a servo tester( Those blue things, you must have seen them.)Without mishap. I bought some new servos, lost my old tester , bought a new one, tested my servos, or rather zero them. Thing goes made, all 3 lights on , servo arm back and forth. Tried some different servos , all OK. Sent back servos as possible faulty. Came back ok. So far I have send back a number of the blue things as faulty. I am in a position where some servos perform OK whilst others as described. Been advised that some testers are likely to act up as before. Am I alone with this or not?. Can anyone suggest a tester that is ok with all (Analogue) servos not a selected few. That does not cost an arm and leg that will work with all servos. Can anyone comment about say a particular servo condition that may do this. Thanks in advance. Bas Quote Link to comment Share on other sites More sharing options...
Phil Green Posted March 6 Share Posted March 6 Is it one of these? The 'end-to-end' swing is a feature of these testers, could it be you're accidentally pressing buttons? Quote Link to comment Share on other sites More sharing options...
stu knowles Posted March 6 Share Posted March 6 I have one of those, the blue one, which has been fine for ages and then it started playing up yesterday in exactly the way that you describe. All three lights on and poor / nil servo control. It's the same today and is on my job list for tonight to look on line and find a new one. Quote Link to comment Share on other sites More sharing options...
leccyflyer Posted March 6 Share Posted March 6 That's a coincidence, I also have one of those and it's been working fine for years, then last week it threw a wobbler and refuses to work. I thought it was likely the NiCd that I use to power it and gave that a charge, but it still wouldn't work, with three different batteries. The lights are on, but no-one's at home. Tried on multiple different servos of various brands, no joy. Then, as suddenly as it had stopped working, at the weekend it started working again. Very strange. Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted March 6 Share Posted March 6 Millennium bug 24 years late? 2 Quote Link to comment Share on other sites More sharing options...
Brian Cooper Posted March 6 Share Posted March 6 I feel like the odd one out. . . my one still works. 2 Quote Link to comment Share on other sites More sharing options...
Bob Burton Posted March 6 Share Posted March 6 As a matter of interest, what functionality would an ideal servo tester provide beyond cantering the output ? Quote Link to comment Share on other sites More sharing options...
EvilC57 Posted March 6 Share Posted March 6 This is my servo tester. It is quite old, and a current Google search for servo testers doesn’t find any pictures of it. It works OK most of the time, however I have found that with some servos if the battery is a bit low the servo will go wild. So it might be worth checking the battery or power supply you’re using is up to scratch. Quote Link to comment Share on other sites More sharing options...
Brian Cooper Posted March 6 Share Posted March 6 13 minutes ago, Bob Burton said: As a matter of interest, what functionality would an ideal servo tester provide beyond cantering the output ? One of the most useful functions is letting it turn the servos from side to side. Personally, I let the tester do this to brand new servos for an hour or so just to see if they will fail. . The first hour being generally regarded as the time they will fail. Servos should be perfectly capable of doing this simple task. If they survive the first hour, they will probably give good service for many years to come. 7 Quote Link to comment Share on other sites More sharing options...
leccyflyer Posted March 6 Share Posted March 6 Aye, that's one of the uses that I'd been setting mine to do, cycling servos for an hour or so "soak" on just that basis that any failure is likely to be encountered early on. 2 Quote Link to comment Share on other sites More sharing options...
Phil Green Posted March 6 Share Posted March 6 I still use the PulStar amongst others If you can find one, the GWS MT-1 is very good, it does servo testing, reads PWM and PPM, prop RPM, etc Quote Link to comment Share on other sites More sharing options...
GaryW Posted March 6 Share Posted March 6 Anytime i want or need to use a servo tester i just plug them into a receiver i no longer used and use my tx to move the servo with the tx sticks using the elevator rudder & aileron channels which also centres the servos prior to disconnecting them from the rx so need to to buy a servo tester Quote Link to comment Share on other sites More sharing options...
GrumpyGnome Posted March 7 Share Posted March 7 I used to do that. Plug in, wiggle for a while, centre, disconnect. Then I got a cheap tester that can centre, and 'exercise' the servo through full movement at a selectable speed. New servos now get exercised in this way, for about 30 mins, before being centred and installed. Came from ebay for a few pounds and has lasted years..... For a while, I had a similar function programmed into my transmitter, but I kept wanting to use the tx for other things! 2 Quote Link to comment Share on other sites More sharing options...
Learner Posted March 7 Share Posted March 7 (edited) Do you all test/exercise your other new components transmitter,receiver,motor,esc etc for an hour before committing to flight or is it just servos? Edited March 7 by Learner 1 Quote Link to comment Share on other sites More sharing options...
Basil Posted March 7 Author Share Posted March 7 The reason I use a tester is; 1) To centre the servo. 2) To exercise the servo for a time period. I have ,hitherto run the tester from a dry cell without any problems.( Check for voltage levels before use), this includes setting up an RX from scratch for testing purposes. During the investigation I tested a number of servos of different types/makes . Some types worked correctly others not, but were consistent within make/type. At one point I returned a number to a supplier on a query. ALL worked correctly. The supplier was using a Lipo /ESC via the little blue jobby. It appears that when tested using a dry cell battery the failure occurred . Well thats the findings so far, testing continues. Why then should a dry cell give rise these problems, and not a LIPO. No doubt some of you have ideas. Many thanks for my rambling. Bas Quote Link to comment Share on other sites More sharing options...
Basil Posted March 7 Author Share Posted March 7 14 minutes ago, Learner said: Do you all test your other new components transmitter,receiver,esc etc for an hour before committing to flight or is it just servos? The supplier I refered to suggests that if a servo is going to fail, its usually in its early life. It is suggested that the servo be cycled for a time before use. Bas Quote Link to comment Share on other sites More sharing options...
Learner Posted March 7 Share Posted March 7 2 minutes ago, Basil said: The supplier I refered to suggests that if a servo is going to fail, its usually in its early life. It is suggested that the servo be cycled for a time before use. Bas Perhaps he had a few testers in stock he needed to sell😉 Quote Link to comment Share on other sites More sharing options...
Learner Posted March 7 Share Posted March 7 Has anyone had a servo fail whilst exercising? Quote Link to comment Share on other sites More sharing options...
Basil Posted March 7 Author Share Posted March 7 2 minutes ago, Learner said: Perhaps he had a few testers in stock he needed to sell😉 It was the servo supplier's comments. He uses the same as me the little blue one. It seems to be a fact that some servos fail. % wise , small I think. Bas Quote Link to comment Share on other sites More sharing options...
leccyflyer Posted March 7 Share Posted March 7 4 minutes ago, Learner said: Has anyone had a servo fail whilst exercising? No, but I have had one fail, in the air, after such a soak test for half an hour, which was a bit of a pain in the neck. I've come to wonder, in light of recent posts, whether that could be frame rate related and will investigate further. I trust the receiver bind rate process to identify whether an 11ms or 22ms frame rate is suitable for the servos installed in a model, but read recently that some analogue servos really dislike the faster frame rate. Perhaps a more sophisticated servo tester than the wee blue ones might be a worthwhile investment. The GWS one that Phil linked to earlier is available on AliExpress. 1 Quote Link to comment Share on other sites More sharing options...
GrumpyGnome Posted March 7 Share Posted March 7 10 minutes ago, Learner said: Has anyone had a servo fail whilst exercising? Yes 1 Quote Link to comment Share on other sites More sharing options...
Brian Cooper Posted March 7 Share Posted March 7 (edited) 40 minutes ago, Learner said: Do you all test/exercise your other new components transmitter,receiver,motor,esc etc for an hour before committing to flight or is it just servos? Yes. . But not motors. 17 minutes ago, Learner said: Has anyone had a servo fail whilst exercising? Yes, but they were later discovered to be fake Futaba servos. Thank goodness for testing. Edited March 7 by Brian Cooper 2 1 Quote Link to comment Share on other sites More sharing options...
Learner Posted March 7 Share Posted March 7 (edited) 9 minutes ago, GrumpyGnome said: Yes 2 minutes ago, Brian Cooper said: Yes. . But not motors. Yes, but they later discovered to be were fake Futaba servos. Thank goodness for testing. Did they work to start with and fail while cycling or not work at all? Edited March 7 by Learner Quote Link to comment Share on other sites More sharing options...
Brian Cooper Posted March 7 Share Posted March 7 1 minute ago, Learner said: Did they work to start with and fail while cycing or not work at all? Failed during cycling. . . About 20 minutes into the procedure. They became hot, slowed down and finally stopped.... they had died. If they had been installed in a model, they would worked.... but not for long. They would have cost a model. 1 1 Quote Link to comment Share on other sites More sharing options...
EvilC57 Posted March 7 Share Posted March 7 (edited) 33 minutes ago, Basil said: The supplier I refered to suggests that if a servo is going to fail, its usually in its early life. It is suggested that the servo be cycled for a time before use. Bas I had a transmitter RF module failure with my Spektrum DX8 Tx 10 years ago when it was only a few weeks old (and under warranty). It was extremely lucky that I was using it with my DJI drone with return to home failsafe on it at the time. Having done range checks previously, I took off and flew away a few yards when the drone climbed to around 60ft, hovered and then flew back and landed at the take off point, all without any input from me. Subsequent investigations showed that the RF output from the Tx had gone extremely low power. Had I been flying anything else (i.e. one of my fixed wing planes) at the time, it would have crashed and I wouldn’t have known why. The RF module was confirmed faulty by Horizon and replaced under warranty. It just goes to show that the safety of our aircraft is dependent on every component in the chain working properly all the time. Edited March 7 by EvilC57 4 Quote Link to comment Share on other sites More sharing options...
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