Macgregor NRF24 FHSS Digimac 1+1 project

[RON]

After viewing the Codamac on ITV's The Royal, It spurred me on to dig out an old Digimac 1 I had hidden away in the dreaded Bermuda Triangle cupboard.
I just love the look of the old blue anodised digimacs. After having a quick chat with Phil I decided I was to convert it to a FHSS Digimac 1 plus 1 system. The Digimac 1 without the plus 1 is great but definitely lacks the functionality of having a throttle, So the plus one it was going to be.
My method is to use that green perfboard stuff, not sure of the correct name but I just like the way you can place your components anywhere you like and just wire them underneath. Everything is mounted on this pcb including the RF module, 3v3 regulator and buzzer.
Jst-Xh sockets were used for the stick pot and throttle switch.I designed a 3d printed tray for the pcb to screw to, keeps it neat.
Transmitter is now complete,
The only thing I'm not 100% happy with is the push button switch, its slightly smaller than the original type used on the plus one, if anyone has a spare, it would be very much appreciated.

I decided to model the receiver on the blue plastic type Macgregor receivers, think they are the "A" series versions. The case is 3D printed in Blue with a screw on bottom. Separate fly leads were required for the servo outputs so I made these up with fresh twisted wire and Dupont connectors going through 6mm rubber grommets.

To finish it off I 3D printed a period battery case in black with fly lead output. Inside it's fitted with a 1s 550ma battery.

Many thanks to Phil for the FHSS 1 plus 1 sketch. Im super pleased with how its turned out and is a really useful addition to the collection.
Don't you just love bringing 50 year old sets back to life.
Now for the retail box!!!!

Here are so photos of the finished project

[Shaun]

Another cracking job Ron.

[Phil_G]

Neater than any Macgregor I've seen Ron!

If anyone is interested in a 1+1 using the NRF FHSS system, the sketch is a merge of two very popular projects, the "Digispark 1+1 Mk3" and the FHSS NRF24 Propo project. The encoder uses any Atmega328P board such as a Nano, Promini or DIY-More.
Receivers are exactly as per the FHSS thread and the 1+1 transmitter mostly follows the FHSS PDF document, there are very few connections:

Stick pot wiper is on A0
Throttle button is on D2
Throttle LED is on D3 (I use a 5v LED to avoid needing a resistor)
Buzzer is on D4
NRF CSN is on D9
NRF CE is on D10
NRF MOSI is D11
NRF MISO is D12
NRF SCK is D13

The NRF connections are exactly as per the guide, pages 2-5: download/file.php?id=11615

Calibration is by switching on whilst holding the throttle button, keep it held, waggle the stick side to side, centre, then release the button.
Optionally the 'mid' throttle position can be somewhere other than 50% by holding the stick slightly off centre when releasing the calibrate button.
It does the throttle LED flashes as before, off is low throttle, fast-flash is mid throttle where the next press is fast, on is full, slow-flash is mid throttle where the next press is slow/off. The throttle position is audibly confirmed with one, two or three pips.
Rudder trim is by dabbing the throttle button whilst holding the rudder stick in the required direction. Throttle cut is by holding the throttle button.
All these features are inherited from the PPM Digimac 1+1 Mk3 encoder, refer to the original doc for more detail:
https://www.mccrash-racing.co.uk/sc/dat ... s1_mk3.pdf

Here's the FHSS 1+1 transmitter sketch, edit your personal guid and hopping channels:

[Wayne_H]

......., the sketch is a merge of the "Digispark 1+1 Mk3" and the FHSS NRF24 Propo Pproject .

Me thinks I shall need to upgrade my MacGregor!

[leccyflyer]

Great job Ron - that looks superb. I love those wee blue anodised sets too.

[RON]

So I said I would make a retail box for this wee Mac, Hope you all like it

Here goes.
The inner box is laser cut from ordinary brown cardboard, designed in affinity designer,
Outer box was a different story, Its made from Daler Rowney blue photo mount card and laser engraved with the text and logo to around 0.4mm so it shows the cream colour underneath. The tongue and groove is designed from a website called
https://www.makercase.com. You just enter the dimensions, fairly straight forward.
I added the little sticker on the end cheek as per original image took from google images, also cut a semi circle as a thumb slot.
In my opinion, the box is nearly as important as the radio inside it, Just gives it 100% finished feeling, also acts as a dust cover when not in use.
Probably as good if not better than buying a brand new 1+1 from a model shop in late 60's, which I could never of afforded.

Here some pics of the finished box

[Phil_G]

I love flying my Vic Smeed 'Poppet' with its Frskified Digimac 1+1, its such a pleasant, relaxed way to fly S/C.
I knew I had another 1+1 somewhere but couldnt find it, and eventually stopped looking.
As often happens, months later, digging for something unrelated, it re-appears, laughing at me cos its been there all the time

Long story short, its now an NRF 1+1, using the usual homebrew FHSS system and the sketch I did for Ron in his opening post.
Of course its nowhere near as neatly done as Rons, I never expected it to be!
Its a DIY-More board and the NRF is in white heatshrink in the right-hand case side cheek.
So here are a couple of untidy pics, I left the original 27Mhz board in there with the idea that a fake PP9 battery shell would hide all the modern bits. Maybe. So Rons 1+1 now has a flying buddy, there are two Digimac 1+1 NRF FHSS sets in the world !

John Kay's original Moonbeam II used pulse proportional (the plan shows an Adams actuator) so I might try it with the Moonbeam.

Edit: NRF FHSS 2+1 Mini - tx viewtopic.php?f=27&t=1885

[RON]

I love that Phil,
Our trannies are best buddies lol.

Nice job on the 1+1, I like the idea of hiding it all in a pp9 or whatever fits in.

Ron.

[RON]

Judging by the crystal Phil,
You’ll need a blue flag on that