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[Unsinkable 2]

I tried to search for 'Futaba T10 cap' but I got about ten thousand just 'Futaba' results. So I'll start my ownHi all,  I have a strange situation and need help please.     
    I have a Futaba T10 cap transmitter it can be cycled from 7 channel to 10 channel. When you do this you turn it off and back on again easy!     
I have chosen a switch to operate a smoke unit, the smoke unit is Powered by a separate 12v system and a brushed ESC with the red wire cut which then plugs in to channel 5.     The smoke unit runs fine with my 6 channel reciever but I don't have enough channels. I switch to the 12 channel reciever, cycle the power (7channel to 10) and everything works except the smoke unit      No matter which channel or switch I assign it to.                 I'm pulling my hair out       Please help. U2

[JimG]

It may not be the number of channels but the receiver. With older Rx's the signal wire voltage was 4.8V and servos were set up to respond to this voltage. Newer receivers have signal voltage at I think 3.3V and older servos will not work at this voltage. This is a known problem with some newer Futaba receivers.

Jim

[Unsinkable 2]

Hi Jim, it's actually an ESC plugged into the channel, both receivers are 2.4g and are still available to buy.


Someone else suggested it's something to do with 7ms and 14ms refresh rate difference of the two receivers. I have no idea really what that is or how it affects the same ESC differently.


Is this a possibility? If so can anyone explain (simply)


Any suggestions as to how I can get my smoke machine working (brushed motor brushed ESC with red wire cut)


The receivers are.... R6014.   And R6017


After just looking on the Internet for model numbers I just found out that the rates are changeable from normal 14 to 7ms...... Now I just have to find out how to do it.... Maybe a chance after all..... U2

[malcolmfrary]

How the signal between the RX and device works -
The device (servo, swtcher, ESC, whatever) is looking at pulses coming from the receiver.  In the elder days, the "standard" was a pulse 50 times per second, with a switch on time of between 1 and 2 mSec, and a quiet period between.  In other words, the "refresh" break was about 18 mSec (1/50 Sec = 20mSec), so a device designed to refresh over a 14mSec period would have no problems. 
Old receivers just repeated what came over the air, distributing the information to the various channels.  Modern "clever" receivers obey their programming.  They take information from the transmitter and process it so that the output rate is independent of the rate of information coming over the air.  This allows for a much higher refresh rate from the receiver, theoretically giving the opportunity for greater precision.
A device designed around having a quiet period (needed so it can tell when the pulse has really ended) of over 10mSec will probably not work on a shorter one.
Futaba have long used a lower signal voltage than most, but, this being reasonably well known by manufacturers, commercially available gear is designed to accommodate it.  A lot of home made circuits that appear on websites do not initially, but usually get a Mk2 version where a modification is incorporated.
That's theory and opinion.  Practice and the real world might differ.

[Unsinkable 2]

Hi Malcolm, nice informatic post, I had to read it a couple of times to process the info but I get the gist. Thanks......


My problem still baffles me..... Yesterday I found out how to change the reciever from 7ms to 14ms (a simple switch on and off whilst pressing a button) this had no effect. I then swapped back to the other reciever to try again but that didn't work. I changed a few settings on my radio and it worked. After I stopped it it wouldn't work again   I am starting to believe that I have an intermittent fault possibly in the ESC. I am going to separate the unit from the other stuff and try it by itself. But before I do I will have to finish something else, just to build up my morale as this problem has eaten about 4days out of my build and I am getting a bit fed up......... U2

[Unsinkable 2]

More digging, more discoveries. I have found out that my R6014 can be switched from high speed to normal but only on the first 6 channels, the rest are unaffected. I also discovered that the intermittent problem with the R6016 (not 7 as written previously) was down to my transmitter having a gyro detector switched on. Once switched off the smoke unit works fine......... But still not on my R6014   I will get to the bottom of this even if it means selling the damn thing and buying an 'inferior' ha reciever. It's supposed to be all singing all blooming dancing, I know what will happen if it doesn't start dancing soon.......      U2