GG Recoder for genuine Rand with 'cycling' Throttle control

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Phil_G
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GG Recoder for genuine Rand with 'cycling' Throttle control

Post by Phil_G »

This has been on my mind so instead of going flying its done, & working fine.
The Rudder & elevator functions are unchanged, same mark/space and rate response as always, but now a third channel input controls the bridge as follows:
Channel 3 > 1650uS equivalent of full tone, bridge held one way
Channel 3 neutral (+/- 150uS) normal mark/space and rate operation
Channel 3 < 1350uS equivalent of no tone, bridge held the other way.

Ideally of course you need a sprung-centred channel, or an "up/down" toggle or buttons, otherwise you have to remember to manually centre it.

Connections are rudder P0, elevator P2, throttle P4, and the output is on P1 - so its the same as the existing recoder with just the addition of the P4 throttle input. Note that the throttle input needs to be a self-neutralising function, not a conventional friction 'throttle stick'.

See attachment in 'Files' section viewtopic.php?f=7&t=756#p6001





digispark_recoder2rand.jpg

digispark_recoder2rand_sep_bat.jpg
Tobe
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Location: Varberg or Stockholm, Sweden

Re: Rand Actuator Throttle control

Post by Tobe »

Brilliant and unselfish as usual Phil
Quick question, could something similar be done instead, as an alternative/choice on the Arduino Encoder 2 ch + progressive throttle encoder board?
My thoughts here is that also those running old and/or Pic recorders could benefit w/o necessarily modifying the actuator especially if they are running original Rands with separate power supply.
My question would be of the possibility to modify the transmitter encoder like the 2ch + progressive throttle with an option to choose between cycling or progressive throttle? In such way the recoder per se don't need to be modified.
The purist GG would probably fly with a converted transmitter with 2 ch + progressive anyway
Last edited by Tobe on 29 Jul 2019, 17:52, edited 3 times in total.
Cheers,

Tobe
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Phil_G
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Re: Rand Actuator Throttle control

Post by Phil_G »

Ah I see what you mean Tobe, yes, for this particular version of the recoder ideally we need a transmitter with 3 channels, of which two are propo for rudder & elevator, and one is a centre-biassed toggle or the equivalent buttons.
When I get a mo I will add this to the existing 'progressive throttle' encoder [DONE! the GG transmmitter encoder now has the option of either throttle setup, so the same tranny can be used for genuine Rands and Tobes without changes other than flicking a switch.]
:D
JohnH
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Location: Eden, MD USA

Re: Rand Actuator Throttle control

Post by JohnH »

Phil,
Marvelous! Thank you very much.
John H.
"Here's another fine mess you've gotten me into."
rudderonlybird
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Re: Rand Actuator Throttle control

Post by rudderonlybird »

Amazing. I have to stretch just to implement what you and Tobe do, and coming up with these systems or modifying them is way beyond me.

Thank you both!

Marc
Tobe
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Re: Rand Actuator Throttle control

Post by Tobe »



Here is a set up with the Digispark ATTyni85 with cycling throttle which you should clearly see when I'm moving the rudder stick. You will notice also that at one point I disconnect the elevator to highlight the recoder going into rudder only mode, the yellow wire. With this setup there will be up to 9 wires going out from the recoder if the option with separate power supply to the actuator is chosen like it would be running an original Rand LR-3. I have to apologize for not running an original Rand but will as soon I'm able to reach my attic...I'm working in Stockholm but my residence/attic is on the Swedish west coast close to Gothenburg.
20190729_161350.jpg
Cheers,

Tobe
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Phil_G
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Re: GG Recoder for genuine Rand with 'cycling' Throttle control

Post by Phil_G »

To complement the 'cycling' Recoder the GG transmitter encoder now has a selectable throttle option.
These terms are easily confused, so to clarify, the "GG Recoder" is the bit that sits inside the model between the receiver and the GG actuator, converting 'modern' servo signals to 'period' GG style mark-space and rate-controlled pulses for rudder & elevator - with Tobe rudder/elevator actuators, throttle is independent of GG, via the usual ESC or throttle servo.

The GG recoder can be used on any conventional R/C set, but some have wanted to convert a genuine period GG transmitter. These generally had joystick control of rudder (varying the mark-space of the transmitted tone) and elevator (varying the repetition rate of the tone) and also throttle which was controlled by a full continuous tone to steadily move towards high throttle, and no tone at all to steadily move towards low throttle. The actual control was either a two-way centre-biassed toggle (like reeds) or two separate buttons for higher & lower throttle.

To date these transmitters have been converted using a variation of the 7ch encoder, having just two proportional channels and a 'progressive' throttle channel controlled by the two buttons or throttle toggle. At the receiver end, the throttle channel would drive either an ESC or a conventional servo which directly controlled the throttle.

The 'cycling' version of the GG Recoder allows the original Rand throttle to be used instead of a throttle servo. For this it expects to see a channel which sits at 'neutral' with the buttons/toggle giving extremes of travel to nudge the 'cycling' throttle up or down.

So when converting a GG transmitter we have two different throttle situations - one gives 'progressive' control of a conventional servo or ESC via the up/down buttons or throttle toggle - and the other sends a channel which is neutral unless either button (or toggle) is pressed, like a reeds channel, ideally we need a sprung-centred channel, or an "up/down" toggle or buttons, otherwise you have to remember to manually centre it.

Its labouring the point but the "GG transmitter encoder" now has the option of either.
With a link in place the throttle channel is neutral, up or down according to the buttons/toggle
Without the link the throttle is progressive as it always was on this encoder.
So its 'link absent' for throttle independent of GG directly to a servo or ESC (eg a Tobe setup)
and 'link in place' for the 'cycling' version of the GG Recoder with a genuine Rand throttle linkage.

It all works great on the bench but I think John H is going to be the first to try it out in practise :D

Cheers
Phil
GarydNB
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Re: GG Recoder for genuine Rand with 'cycling' Throttle control

Post by GarydNB »

Yeah, thanks Phil, that's what I thought.... :roll:
Gary
Tobe
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Re: GG Recoder for genuine Rand with 'cycling' Throttle control

Post by Tobe »

...mmmm
It would be airborne already if it wasn't that I don't fly IC much anymore
If it ain't on YouTube it doesn't exist or



You will see in the picture the complete set up where I supply the right voltage to the actuator via a step down unit from Pololu S7V8A and added a cheap voltage display just to show off :twisted: , remember here that some Rands are on 2.4 volt and some on 3.6 volt. You will identify which one by looking at the bottom of the actuator where there should be a dot, red for 2.4 volt and black for 3.6 volt. If you by any chance have both kind of actuator you could add a resistor as step down on the 2.4 volt so it can run also on 3.6 volt and you don't have to remember which one was which!
20190804_152257.jpg
Red dot 2.4 volt and black dot 3.6 volt
Red dot 2.4 volt and black dot 3.6 volt
Cheers,

Tobe
Tobe
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Joined: 16 Feb 2018, 06:19
Location: Varberg or Stockholm, Sweden

Re: GG Recoder for genuine Rand with 'cycling' Throttle control

Post by Tobe »

Here is a pic of my set up. You will see the main "board" and a smaller one which is a variable voltage regulator, the small pot is to set the voltage which is checked with the mini voltmeter, with this configuration with this set up it's actually possible to run the full package on 1S as the regulator can also step up the voltage...All leads are connected directly to the receiver which is powered by the regular flight pack.
Very well done Phil as this new recoder brings GG to the highest level.
As voltage regulator I use Pololu S7V8A

20190821_080433.jpg
Cheers,

Tobe
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