Digimac II and IV

[leccyflyer]

With interest in classic radio control of my youth being reawakened as a direct result of this forum, I put a couple of bids on a well known site for the desirable radio gear that I would have loved to have at the time. I've ended up with a couple of transmitters in that iconic brushed blue aluminium, a receiver and a couple of servos. I hadn't recalled the servos being that big, but when I compared them to a Futaba S148 they were pretty much the same.

They appear to be in decent condition, with no obvious signs of black wire corrosion, though I haven't tested them yet. The Digimac II outfit is fed by AA sized dry cells, but the Digimac IV is fitted with a DEAC. I haven't seen a DEAC for half a century !

In due course I plan to convert the Digimac IV to 2.4Ghz, but I'd like to at least try the Digimac II on 27mhz in an appropriate vintage model. Ultimately I hope they will both be converted, thanks to this forum, all the excellent resources available here and the incredibly helpful contributors.

[RobertC]

Hi There
Looks like you got a couple of nice bits of vintage Wee macgregor
You’ll find a host of knowledgeable experts on here and all willing to give you advice and know how ..
I’ve seen a couple of two channel conversions done one by Stuart , one by myself …
Have fun and ask away …

[leccyflyer]

Thanks Robert.

I was wondering whether to get the conversion done before going to Ponte, but I think I've got enough to do, so will leave it until afterwards and pick a few folks brains, as I've never really done anything like that before. I have one of Stuart's Lemon 2.4ghz modules and really fancy making the mod I think I have seen on here of adding a button, enabling the Digimac to operate as a simple single channel set, as well as a proportional multi channel.

[Nick M]

Finished my Digimac IV conversion about a month ago

Used an old Radiolink 2.4 set - but made the uninformed error of using standard pots and not realising that I needed 60 degree ones

Fiddled endlessly and in the end 3d printed 3 shims per pot to be able to use the Radiolink ones

Bit tattier case but worked well with the Wizard of Oz slope soaring

I also converted another Radiolink sey into a reeds set (and thanks for the help on this forum sorting out resistor values)

That means I can keep the same rx in the model and fly with either set - Radiolink rx are a really quick rebind

[leccyflyer]

That's great.

Did you replace the pots on the original sticks with those from the Radiolink set?

I removed the DEAC from the Digimac IV today, as I definitely won't be using it. I'll need to search out exactly what needs to be done for the conversion, namely what additional mods need to be made before putting in one of Phil G's encoders and the Lemon RF module. I was hoping that it was a case of using the existing stick units and the output from those.

[PaulJ]

FWIW, I converted a Digimac IV some time ago and used the facilities on Phil's encoder to make it into a Digimac VI.

It really was very simple...... Out with everything except the sticks and on/off switch, and in with Phil's encoder and an Orange DIY transmitter module. All original pots. I made up a small base-board to mount them on It is held in the case using the same screws as hold the on/off switch. In order to keep it looking as original as possible I made up a small aluminium bracket to hold the Rate and Expo pots inside the case though they could of course be mounted externally if you wish.

Paul

[leccyflyer]

Thanks Paul - that looks great. I take it the buttons on top are your single channel button and a bind button?

[PaulJ]

I didn't fit a single channel button, the red button is the bind button and the black "knob" is actually a slider for the Aux channel (6)...... I did also have a Digimac VI but it had a damaged case so I removed the slider and u/c switch from the 6 channel Digimac and converted the Digimac IV to 6 channels.

Paul

[Nick M]

If I remember the original pots were 50 k and Radiolink oIn the end I used the end were 5k

The ones I bought worked - but servo arm travel was minimal

In the end I used the Radiolink ones but this required the extra 3 d printing - needed to extend the shart and then make shims for the stick bit and the stick mounting bit

Could have bout 60 degree pots but quite enjoyed the challenge. Printed various failed versions, eventually got it right, then printed with high infill to make sure no embarrassment in flight...

I tried the original pots just in case and not enough servo arm travel

Your conversion looks neater than mine - I had to angle the motherboard to get it to fit (mounted on foamboard lugs)

That's great.

Did you replace the pots on the original sticks with those from the Radiolink set?

I removed the DEAC from the Digimac IV today, as I definitely won't be using it. I'll need to search out exactly what needs to be done for the conversion, namely what additional mods need to be made before putting in one of Phil G's encoders and the Lemon RF module. I was hoping that it was a case of using the existing stick units and the output from those.

[leccyflyer]

The postie has just delivered Part III of my vintage MacGregor Radio Control Project, a nice clean Digimac III transmitter.

No immediate sign of any corrosion and this one has two power packs, in the form of black rectangular blocks of cells - not the familiar DEACs of the Digimac IV set. Nice feel to the ratchet on the left hand throttle stick and when it's been converted to 2.4ghz, it will be dedicated to a particular 3 channel model.