DigiSpark 3-channel propo encoder with single-channel, V mix, inactivity + softlock alarms

Single to Multi propo
Post Reply
User avatar
Phil_G
Posts: 597
Joined: 15 Feb 2018, 23:32
Contact:

DigiSpark 3-channel propo encoder with single-channel, V mix, inactivity + softlock alarms

Post by Phil_G »

See edits!
I've just done a 3-channel EK Logictrol with a DigiSpark, see photo, it has a a Flysky RM002 RF module and like the 4ch sketch its based on, it has all the usual reversing, V-tail or elevon mixer, S/C emulation, soft throttle lock, inactivity warning (with servo waggling in case you left the rx on too) etc but doesnt use P5 so doesnt need the fuse programmer, making it an easier DIY build.
It uses a lithium battery made from two LIDL 18650 "drill battery" cells.
Like all of my builds, the inside isnt at all tidy - because the pot tags look very delicate, I used all the original cabling rather than risk disturbing the pots. Note the dangling S/C button with the buzzer mounted on it.
Not sure whether to drill an extra hole for S/C or not, I think I'll probably leave it hidden inside.
The DigiSpark encoder is the tiny white blob and the Futaba-style Flysky module is mounted side-on to the camera, the RM002 has a fixed aerial so the whole thing just pokes up through an enlarged aerial hole - its probably the easiest module of all to install!
Cheers
Phil


IMG_20190704_233515.jpg

IMG_20190704_235836.jpg

digispark_3ch_encoder_v2.jpg


There are a lot of wires and its a very small board, so its as well to keep them as tidy as you can:


IMG_20190918_111230_196.JPG

IMG_20190917_181624_674.JPG


I was trying to remember where the Logictrol came from, its been on the shelf awaiting conversion for a few years. I think I recall Shaun being given a pile of various Logictrols to share out, and I chose the 3ch as it was a bit different. Unfortunately I dont remember who donated them, sorry! but thank you whoever it was!

The Flysky module works with the F949R 'indoor bricks' and I have a stash of 3mm depron, so I might make an 'indoorneezer' for it :D I've never been to an indoor meeting, never flown indoors...

Cheers
Phil

Edit: One extra over the usual inactivity warning - if you've inadvertently left the receiver powered up as well as the transmitter, the inactivity alarm also waggles the rudder to let you know. Cool eh? :D

Edit 2:
I've updated this sketch with the dual maps, the new calibration procedure is to centre all trims, switch on with the S/C button pressed, and keeping it held, waggle all the sticks to their extremes but then (and this wasnt necessary before) to centre the sticks including throttle before releasing the button. The highest & lowest values are saved like before, but additionally the centres are now stored and the encoder now uses a separate map for either direction the stick is moved. This ensures that even a slightly non-linear stick pot will map accurately.
This ensures that stick-centre is channel centre whilst full travel is equal in both directions.

Edit 3: Added the "Power on with throttle open" warning, which indicates that the soft throttle lock is active - similar to the 7ch encoder.
Attachments
digispark_3ch_propo_sc_v2.ino
(8.01 KiB) Downloaded 330 times
digispark_3ch_propo_sc_v2.pdf
(10.6 MiB) Downloaded 378 times
NeilMac
Posts: 165
Joined: 04 Feb 2019, 22:07
Location: Nth Somerset

Re: DigiSpark 3-channel propo encoder with single-channel, V mix, + inactivity alarm

Post by NeilMac »

These DigiSpark setups are brilliant and make the whole job of fitting all the gubbins in the tin so much easier.

Hoping to get an opportunity to try the 4 channel version out soon. ;)

Neil
"I'm your huckleberry, that's just my game"
pulserudder
Posts: 21
Joined: 21 Feb 2018, 02:01
Location: North Carolina

Re: DigiSpark 3-channel propo encoder with single-channel, V mix, + inactivity alarm

Post by pulserudder »

Love seeing this old transmitter given a new life. Very nice job.
pulserudder
Posts: 21
Joined: 21 Feb 2018, 02:01
Location: North Carolina

Re: DigiSpark 3-channel propo encoder with single-channel, V mix, + inactivity alarm

Post by pulserudder »

Flying indoors is fine, except for all the walls and ceilings. :shock:
ChrisBe
Posts: 13
Joined: 16 Feb 2019, 06:49

Re: DigiSpark 3-channel propo encoder with single-channel, V mix, inactivity + softlock alarms

Post by ChrisBe »

Hey Phil! Just completed converting a vintage World Engines 3 channel Digit Midget transmitter with one of your nicely done prewired 3 channel DigiSpark propo encoder boards and an FrSky DHT transmitter module. It turned out to be a rather enjoyable project. The information that you provide in supporting these efforts is always invaluable and greatly appreciated. Thinking that this radio will go great with a Sterling Mambo that I still have in a box. Again a rather enjoyable and rewarding experience.👍
Needs tidying up and final battery instillation. Stick cal and functional test with bound reciever good. Fun project!
Needs tidying up and final battery instillation. Stick cal and functional test with bound reciever good. Fun project!
World Engines 3 channel Digit Midget with DigiSpark 3 channel encoder board.
World Engines 3 channel Digit Midget with DigiSpark 3 channel encoder board.
User avatar
stuart mackay
Posts: 501
Joined: 01 Mar 2018, 10:38
Location: Swaffham, Norfolk
Contact:

Re: DigiSpark 3-channel propo encoder with single-channel, V mix, inactivity + softlock alarms

Post by stuart mackay »

Thanks to a swap with the great enthusiast that is Mike Kitchen and the support of Phil G, I have now completed a Restomod of the Simprop Digi 2+1 using the Digispark and FrSky XHT RF module. A 500 mah Turnigy Lipo powers the set up.
Turned out great and really pleased with the end result...another old radio lives to fly again!
A-2.jpg
A.jpg
User avatar
_AL_
Posts: 160
Joined: 17 Feb 2018, 01:09
Location: Sydney Australia

Re: DigiSpark 3-channel propo encoder with single-channel, V mix, inactivity + softlock alarms

Post by _AL_ »

Time to have a whack at a couple of these.
First things first, make up the programming adapter board. All those little bits of wire finally came in handy......
Tried to be neat & still managed to bugger it up. It'll still work.
Looks like the hardest part will be getting a push button NC switch. None available at the local electronics shop. If worst comes to worst, I'll use a jumper.
Attachments
Digispark programmer2.jpg
Digispark programmer1.jpg
bluejets
Posts: 316
Joined: 19 Jun 2019, 04:09

Re: DigiSpark 3-channel propo encoder with single-channel, V mix, inactivity + softlock alarms

Post by bluejets »

_AL_ wrote: 01 Feb 2024, 11:42
Tried to be neat & still managed to bugger it up.
Best to clean board first (steel wool) then flux, flux and if all else fails, more flux.
User avatar
_AL_
Posts: 160
Joined: 17 Feb 2018, 01:09
Location: Sydney Australia

Re: DigiSpark 3-channel propo encoder with single-channel, V mix, inactivity + softlock alarms

Post by _AL_ »

I'm more concerned with installing everything 1 row too far over.
All going well I'll upload the sketch tonight.
User avatar
Phil_G
Posts: 597
Joined: 15 Feb 2018, 23:32
Contact:

Re: DigiSpark 3-channel propo encoder with single-channel, V mix, inactivity + softlock alarms

Post by Phil_G »

_AL_ wrote: 03 Feb 2024, 06:45 I'm more concerned with installing everything 1 row too far over.
If you remember Al I did that very same thing myself in the original Digispark programmer thread... :)
viewtopic.php?p=5889#p5889
Post Reply