trebor Posted February 20, 2017 Share Posted February 20, 2017 I am thinking of switching over from Spektrum to Taranis but just noticed that the voltage requirements on the receivers are slightly higher on the Taranis. As I have a few glow powered planes with 4.8v nimh packs in would I be better upping to 6v if my servos can handle it. Or will I be ok ? Quote Link to comment Share on other sites More sharing options...
Fatscoleymo Posted February 20, 2017 Share Posted February 20, 2017 Been running 4.8v nimh on my Frsky stuff for 5 years now...no issues. Fats Quote Link to comment Share on other sites More sharing options...
trebor Posted February 20, 2017 Author Share Posted February 20, 2017 I was just worried I'd have to change them as most Spektrum Rx's have a low 3.5v compared to 4v on Taranis. Quote Link to comment Share on other sites More sharing options...
MattyB Posted February 20, 2017 Share Posted February 20, 2017 Posted by trebor on 20/02/2017 14:20:16: I was just worried I'd have to change them as most Spektrum Rx's have a low 3.5v compared to 4v on Taranis. This is slightly ironic. I have never read the official FrSky RX low voltage specs, but I can tell you that one of the main reasons they became popular is precisely because their low voltage performance was so much better than most Spektrum RXs at the time (though Spek have made steps forward in this regard with their later RXs no longer exhibit high reboot voltages and slow reboot times). Here is the original review from Bruce at RCModelReviews that brought FrSky to the attention of many of us - two pictures tell a thousand words... Still working at 2.8V: Finally non-functioning at 2.2V, well below that where you servos will have stopped working: Edited By MattyB on 20/02/2017 15:30:31 Quote Link to comment Share on other sites More sharing options...
Former Member Posted February 20, 2017 Share Posted February 20, 2017 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
trebor Posted February 20, 2017 Author Share Posted February 20, 2017 Thank you gentlemen, just placed an order for one and a couple of dx Rx's to practise with. I have an old Futaba and Dx6 which I will phase out gradually if I get on with it. Ps the battery pack in the dx6 is rubbish so I'm onto a winner Edited By trebor on 20/02/2017 15:54:00 Quote Link to comment Share on other sites More sharing options...
Former Member Posted February 20, 2017 Share Posted February 20, 2017 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Geoff S Posted February 20, 2017 Share Posted February 20, 2017 Just a little warning about charging a NiCad using the in built charge circuit in a Taranis transmitter : Don't under any circumstances try to use an 'intelligent' charger. Just use the provided simple raw DC wall wart charger supplied and rely on the internal charge circuit to control battery state. I wrecked my first Taranis by doing just that. Fortunately, with a bit of on-line help, I was able to identify the chip ( a surface mount MosFet) and replaced it myself (I'm a retired electronics engineer so had a bit of experience). I now always recharge the transmitter battery pack by removing it and using an external charger. I confessed my stupidity at the time but memories fade with time and I wouldn't want anyone else to repeat my mistake. Receivers? Never had a problem, but most are powered from esc BECs. In any case the voltage spec on FRSky receivers is very wide. Geoff Quote Link to comment Share on other sites More sharing options...
trebor Posted February 20, 2017 Author Share Posted February 20, 2017 Does it have a display light to tell you the battery is full ? I take it it shuts off ok Edited By trebor on 20/02/2017 16:08:58 Quote Link to comment Share on other sites More sharing options...
MattyB Posted February 20, 2017 Share Posted February 20, 2017 Yes, of course. Just plug in and leave til the green LED goes out. Quote Link to comment Share on other sites More sharing options...
Former Member Posted February 20, 2017 Share Posted February 20, 2017 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
trebor Posted February 20, 2017 Author Share Posted February 20, 2017 That's ok then, as long as it's not too complicated Had me worried for a minuite. Quote Link to comment Share on other sites More sharing options...
Phil Green Posted February 20, 2017 Share Posted February 20, 2017 Hi Trebor, just to confirm Matts comment, Frsky receivers are remarkably tolerant of low supply voltage, I was fortunate to be in on the frsky beta testing 7 years ago and I've tested them on a calibrated lab supply down to 2.18v where very few servos will operate. Many of us run Frsky receivers from a single 4.2v lipo cell without a booster. The comparison with Spektrum made me smile - probably the least tolerant of LV with relatively high dropout regulators that spawned the whole 5-cell thing Cheers Phil Quote Link to comment Share on other sites More sharing options...
trebor Posted February 20, 2017 Author Share Posted February 20, 2017 I ment to say the receivers I got with it were X6r and X8r to practise on. The "6"shows it giving flight pack voltage but the instructions for the "8" didnt. Hopefully they both will along with the signal strength. Quote Link to comment Share on other sites More sharing options...
Chris Bott - Moderator Posted February 20, 2017 Share Posted February 20, 2017 They will both give receive level and Rx battery volts, Trebor. The X6R also has a second input that will read another voltage. On top of that, both will handle many other telemetry sensors too. Quote Link to comment Share on other sites More sharing options...
trebor Posted February 20, 2017 Author Share Posted February 20, 2017 They show a low voltage of 4v so would that be the best setting for the alarm ? Quote Link to comment Share on other sites More sharing options...
Chris Bott - Moderator Posted February 20, 2017 Share Posted February 20, 2017 I think I'd set it to something like 1.1v per cell for NiMhs so that would be 4.4V. You want it to go off when there's still some useable charge left in the battery. Don't forget that the voltage will also reduce as you use more servo power, so towards the end of battery discharge you might find the alarm sounding when you stir the sticks a lot, and being silent again when you're not. Quote Link to comment Share on other sites More sharing options...
trebor Posted February 20, 2017 Author Share Posted February 20, 2017 I'll test it out on my old Funcub first Quote Link to comment Share on other sites More sharing options...
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