Tim Mackey Posted July 29, 2008 Share Posted July 29, 2008 Sorry for sounding a little dramatic in the header, but having done some initial testing of "brown outs" and the like on a thread yesterday, I have done quite a lot more today, and the results are quite startling - if you fly Spekky gear ( and even if you dont ) you might want to see the latest test results which concern servo current comsumption, signal loss re-boot times, and more "brown out" scenarios.I have only just finished filming the results and have a lot of text and film editing to do, so unlikely to be posted until tomorrow...but please .... visit the thread called "Brown outs and Grey areas" later tomorrow, and get ready to be surprised - well I was !PS for those who dont know... a brown out is NOT a political rebellion movement PPS you may also want to see the discussion happening here too ! Quote Link to comment Share on other sites More sharing options...
Andy Harris Posted July 30, 2008 Share Posted July 30, 2008 TimboYou could do with some linkage to the 'Brown outs' thread - I guess you're aware that searching on the forum has its foilbles ... Andy Quote Link to comment Share on other sites More sharing options...
Tim Mackey Posted July 30, 2008 Author Share Posted July 30, 2008 Apologies Andy...post amended. Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted September 17, 2008 Share Posted September 17, 2008 Timbo, this may not be the ideal place to put this, but I think that it may be relevant.. I have a Dalotel now on JR DSX9 but previously on JR 3810. The radio makes no difference. I used MG995 cheapo digi servos and found that occasionally one would suffer a delay in returning to neutral; changing the servo seemed to help for a short time. I have just installed some decent Multiplex digi servos and the problem re-occurred, but only with all servos plugged in. The Rx pack is a 2000 NiMh, and when I measured the output with all servos operating it was below 3.8V. Changing to a 2000 Nicad has completely cured the problem. Could this be the cause of some brown outs? I never felt completely in control with the NiMh`s (tested to hold full capacity). Should we only use Lipo`s (which I do not trust) or Nicads with digi servos? Quote Link to comment Share on other sites More sharing options...
Tim Mackey Posted September 17, 2008 Author Share Posted September 17, 2008 Well whether we like it or not, NiCd will soon be almost impossible to source so its either NiMh or Lithium in future.Some cells are poor at delivering their stuff - you didnt say what physical size the 2000 cells were, or indeed the voltage ( 4 or 5 cell ? ) I suspect it is down to the former.... for instance, typical AA size cells will simply NOT supply good current flow irrespective of the capacity, and for anything much bigger than 2 or 3 digital servos I would suggest at least subC size packs....... and for extra margin.... 5 cells. In my IC models I now use 2 cell LiPos and a good regulator / solid state switch system like the powerbox digiswitch.PS I trust EVERY model I fly to Lipo...even all my sloper's radio gear are Lipo fed. Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted September 18, 2008 Share Posted September 18, 2008 Timbo, yes, they were AA size but not had the problem in other models. The 4.8V pack is now C cells. Had far too many Lipo failures in lecky models (including top brands) to trust them as yet in anything which does not have a BEC. Martin. Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted September 19, 2008 Share Posted September 19, 2008 Timbo, flown the model today with the new set-up and now feel completely `locked in` and in full control for the first time in its 2 year life. But!!! on switching on the DSX9 for the second flight the Rx refused to respond until it was switched off and on again. Could not repeat it and no further problems but has anyone else experienced this? There was one other 2.4 in operation at the time. MM. Quote Link to comment Share on other sites More sharing options...
Doug Ireland Posted September 21, 2008 Share Posted September 21, 2008 Hi Martin,Same thing happened with my DSX9 the other day while setting up control throws at home. Hopefully its nothing serious! Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted September 21, 2008 Share Posted September 21, 2008 Hi Doug, Bought an AR6100 yesterday and it took several attempts to bind properly without flashing LEDs but is now fine. Maybe some minor problems have still to be sorted out, but I still have more faith in this than 35mHz. Quote Link to comment Share on other sites More sharing options...
Roy Hill Posted September 22, 2008 Share Posted September 22, 2008 Hi folks, re no initial response,same has happend to me, suggest you move the tranny further away prior to switching on,seems to work ok then(could be swamping if too close?), or like me just confused!! regards, roy. Quote Link to comment Share on other sites More sharing options...
stuey Posted September 23, 2008 Share Posted September 23, 2008 I think a lot of the high capacity AA Nimh cells have a lot of internal resistance and cannot stand a high load without the voltage dropping. When i was racing 1/10 electric buggies and Nimh cells appeared, they lacked "punch", the ability to deliver power under high loads. It took quite a while for the cells to develop and improve to the same level as the old Nicads. I reckon there is a chance that Nimh cells that have a lower capacity for the same cell size, may have lower IR and may be more suitable for high power servo requirements. Anyone able to test this?? Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted September 23, 2008 Share Posted September 23, 2008 Stuey, I think that you are correct. Come to think of it, I do not recall a problem when using the model on 1300mAh hydrides. The higher capacity cells can certainly only be charged at a low (1/10C) rate, so the discharge max. current would probably be much less than a lower capacity pack. Just wondering how the 1500mAh pack supplied with the JR DSX9 would perform with digi servos since I presume that they would expect us to use them with their currently top of the range set. Quote Link to comment Share on other sites More sharing options...
stuey Posted September 24, 2008 Share Posted September 24, 2008 I dont know what servos come with the set, but if it comes with 4 digi servos i would guess the pack should be capable of driving them without the receiver voltage being compromised?? Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted September 24, 2008 Share Posted September 24, 2008 It does not come with any! Quote Link to comment Share on other sites More sharing options...
Doug Ireland Posted October 1, 2008 Share Posted October 1, 2008 Have you seen the picture on page 51 of the October issue of RCMW? If that doesn't fill you with confidence then nothing will! Quote Link to comment Share on other sites More sharing options...
Tim Mackey Posted October 1, 2008 Author Share Posted October 1, 2008 Oy...no swearing on this RCME forum Doug Quote Link to comment Share on other sites More sharing options...
Doug Ireland Posted October 1, 2008 Share Posted October 1, 2008 Quote Link to comment Share on other sites More sharing options...
Tim Mackey Posted October 1, 2008 Author Share Posted October 1, 2008 So just what is this picture in "the other mag" ( spits and coughs ) showing then Doug? Quote Link to comment Share on other sites More sharing options...
Doug Ireland Posted October 1, 2008 Share Posted October 1, 2008 It was an experiment to see at what temperature the AR9000 rx assembly would fail. The people conducting the test put the rx in a test chamber with the battery and servos outside. They got the chamber up to 307 F before the rx melted and quit!Impressive! Quote Link to comment Share on other sites More sharing options...
Tim Mackey Posted October 1, 2008 Author Share Posted October 1, 2008 That is good ! Quote Link to comment Share on other sites More sharing options...
Brian Parker Posted October 1, 2008 Share Posted October 1, 2008 More a publicity dig at their rivals than a revelation. An IC would have reached its shut down temperature of 125C- 150C (302F), the oven temperature reading (307F) would be ahead of receiver temperature. It was the case that melted not the actual receiver. Would have been impressed if it had worked again after cooling down. Does confirm that the components are to a high specification.Case could be of a higher spec though! Quote Link to comment Share on other sites More sharing options...
Doug Ireland Posted October 1, 2008 Share Posted October 1, 2008 Just no pleasing some people. What more do you want Brian? When was the last time you had an electronics package operating at those temperatures? I work in the oil industry and some of our down-hole electronic equipment has to work at temperatures above 150C and it does it quite nicely thanks! Quote Link to comment Share on other sites More sharing options...
Brian Parker Posted October 1, 2008 Share Posted October 1, 2008 Doug, I don’t want anything!!Just making a light hearted comment on an advert. Quote Link to comment Share on other sites More sharing options...
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