Futaba 2.4GHz with caution

[Tim Mackey]

Most if not all new sets come with NiMH these days - green brigade at work .

Likewise they nearly all come with a wall wart style charger,( Spektrum supply NO charger at all with their sets, and possibly a good thing IMO ) - and unless it is a very clever peak detect style charger, ( which is highly unlikely ) then I suggest you charge your packs for the recommended time only, as stated in the manual and THEN REMOVE THEM FROM CHARGE.

[Alan Shipley]

Thanks lads for all the imformation its been very helpful. Must get back to work now.

Alan

[Alan Shipley]

I gave Ripmax repair centre a call as David suggested. The help I got was brill, he knew the  --                   FP-T8JN model and said from info given felt sure he could help. He pin pointed the problem and thought I was able to fix it with a steady hand & soldering iron.

Good news, with in half an hour my beloved Futaba FP-T8JN was back in good working order. All for the cost of a phone call and to this brill site & forum.

Thanks for your help lads

[Tim Mackey]

Thats excellent Alan, well done

[Robert Bonard]

Hi      what do you reckon to this then.   Last year i bought my Futaba TXE6 from a trade stand at the Nationals and was well pleased with my purchase of my first trany only to discover in the early part of this year there was a bit of a problem with a number of these TXs. Having been informed the best thing to do was to take it to my nearest model shop to get checked out. This I did and was amazed to hear the shop owner inform me he was unable to test my TXE6 because he only had specialist testing equipment "delivered in a large truck from Futaba to his model shop", for the actual models he personally sold and would only be able to test my TX if I left it with him for a few days so he could contact Futaba for these very special code details for the said model that I was holding out in front of him over the counter to see. His rubbish explanation for not testing my TX was longer than I've spent at a dentist.   He then showed me the door.   I will not give this shop the satisfaction of saying its name , only to say its in Scunthorpe. I wonder what Futaba will make of this shops attitude,and is it being experienced elswhere.

[Chris Dowsett]

Hi Robert 

Futaba has not really given a proper technical explanation of the problem they had.   That's had a domino effect on distributors, model shops and fliers because no one has enough confidence to offer much support.    

Your model shop should probably have said they were 'bewildered by it all'.  Mine, in Surrey, offered good advice -  "Avoid turning the TX power off and on quickly". 

Wonder what the trade stand will say at this year's Nationals? 

[Chris Dowsett]

Since I started this thread there have been many issues both good and bad.  I have counted 9 groups though it not easy picking them out.  Some should be seperate threads but not  yet.  Here they are with some examples (complete with emotions):-

 #1 Power management :  Failsafe levels ,  Switching off/on (boot up), Servo buzz ,

#2 Pre-flight: Low power range test

#3 Flight:Trim changes

 #4 Design: Servo lead connection

#5 Manufacture:

 #6 Supply:

#7 Marketing:

#8 Installation: Retrofit

#9 Servicing: Ripmax

 The smiley's should help a bit.  I may go back and edit some of my postings but I will also post something shortly about #1 as an example.    This will cover the promised telemetry tests!

[Chris Dowsett]

Flight:  Here are a couple of typical results from my flight log for the Harmony with telemetry data. 

Thursday 17th July  Raja(mountain) 14km/h forecast.  Evening flights in marginal conditions with wind falling off.

H83   Height Max 112ft Min  -15'    Battery voltage Max 5.1volts Min 4.9volts Flight duration 5mins

Friday 18th July Beach 32Km/h forecast.

H86   Height Max 132ft Min  -15'    Battery voltage Max 5.1volts Min 4.7volts Flight duration 21 mins

Excellent test flight with a loop and 180deg turn on  a crosswind approach to avoid the new beach bar. 

Battery Management:  The old NiMh 4.8V  flight pack is supporting the 2.4GHz RX and telemetry without problem.   The telemetry gives a verbal warning in flight every 0.1v change.  Once the voltage drops to 4.4v I switch off the telemetry (it no longer works properly).   The Futaba avionics is safe down to 3.5v with analogue servos.

 Design:  I am used to PCM on 35MHz it allows setting up failsafe on all channels hence crow braking. Both my Futaba receivers have failsafe on channel 3 only.  Works fine if you have a throttle!

Battery Management: I have run some ground tests with my all carbon Sword.   With a dead cell - presumably where the 3.5 volts failsafe comes from on the Futaba RX.   The Sword has 3 digital servos (and 3 analogues).  As the telemetry is not specified below 4.4volts it's a lot to ask of it.   The servo buzz already amplified by the hollow wings is heard load and clear over the telemetry which produces very strange results.  This is nothing directly to do with Futaba but I do wonder at the wisdom of a fixed 3.5v failsafe.

[kiwibob]

Timbo - forum moderator wrote (see)

ensure you use a good properly designed charger and preferably use a loaded EVM meter / indicator regularly to check the charge state of your packs.

Pardon my ignorance, but what is a loaded EVM please?Is it something like a Hitec powermate battery checker?ThanksBob 

[Chris Dowsett]

Timbo means an old fashioned voltmeter.  It will not take much current when you connect it across the battery so there needs to be load resistor as well.  Same function as the powermate but you have to work things out for yourself.