Two of a Kind

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NeilMac
Posts: 165
Joined: 04 Feb 2019, 22:07
Location: Nth Somerset

Two of a Kind

Post by NeilMac »

Back in the mid 1970's I flew my first RC glider, it was not mine, it belonged to a CL flying buddy who had been given a MacGregor Digimac II and had installed it into a Veron Impala. We had nothing that resembled a 'slope' in the part of Essex where we lived but there was a massive grass covered mound close to where we usually flew, so off we all went and spent the day trying to keep the Impala in the air for as long as possible.

A few years later I had moved to the South West as my dads work had required a move from London to Bristol. I could not find any aeromodellers at my new school, but a couple of guys sailed boats and so I saved, and acquired a MacGregor push button single channel. Sometime in around 1974 the MacGregor was traded against a Waltron Mini2, the version with a throttle slider and a rudder stick. It was used mostly in boats, I was still keen on aircraft, but I really can't remember what models I had, or what their fate was.

At the end of 2018 I retired, and through a few chance google searches I found both my interest in aeromodelling returning and also singlechannel.co.uk and so here we are.

I still have the Waltron, in its original box and wearing my best quality rose tinted glasses I recently bought a complete Digi II set up. Both are on 27mHz and both still work in a manner of speaking, but, like their owner, they are a bit on the creaky side, so a change to 2.4gHz is on the cards and I thought I'd start a 'build' thread.

The Digi II Tx case was pretty grubby, the flash has glossed over the worst of it but you can imagine what years of use and storage have done. Careful use of Brasso on both a soft cloth and also cotton buds got a lot of the shine back, but those water slide graphics have to be treated with care, I have watched enough 'restoration workshop' programs on TV to know that a bit of good old fashioned spit can be used, and so it proved, with Wee MacGregor recovering much of his colour and losing all the grime from around the edge of the decal, the same for all the graphics.

Waltron Mini2
DSC_0009.JPG
MacGregor Digi II, as received.
DSC_0017.JPG
Getting ready for testing.
DSC_0014.JPG
A quick look inside.
DSC_0022.JPG
DSC_0021.JPG
As the Digi II is a mystery to me and needed a thorough clean, I started there first.
DSC_0025.JPG
As I said, the case and all the plastic parts needed a thorough clean, I also wanted to remove the ratchet from the left hand stick and put a spring in its place, as once converted this set will be used in a Veron Impala (in full on retro mode here).

I have an old Futaba 2 channel Tx here which I use for charging loose AA batteries, so that was robbed of the springs from both sticks and the Digi II got a matching pair. Looking at other conversion threads answered the question of how the sticks are kept in place as they are secured to the PCB, simple answer... you leave the PCB and just disconnect the feed to and from it, so, while I wait for Phil G to do his thang with the encoders (a task well beyond me), I will get a couple of FrSky hack kits on order and work will continue once all the gubbins has arrived.

Neil
"I'm your huckleberry, that's just my game"
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RON
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Location: Stokesley North Yorkshire

Re: Two of a Kind

Post by RON »

Hi Neil
Great post, thanks for that.
I absolutely love that Waltron tranny, a great project.

Ron.
G0MBV Class A Radio Amateur, North Yorkshire
Stew
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Re: Two of a Kind

Post by Stew »

What a great post, love the transmitters, and I look forward to seeing and reading more about the conversion.
NeilMac
Posts: 165
Joined: 04 Feb 2019, 22:07
Location: Nth Somerset

Re: Two of a Kind

Post by NeilMac »

Thanks chaps.

Ron, the Waltron Tx is a tiny thing, smaller even than the s/c button MacGregor, but it does have some depth to it. If holding with two hands it is kind of one at the top (on the rudder) and occasionally one on the bottom to save dropping it and to shift the throttle when needed.

At present its new home is a toss up between a Mini-Tyro or a Poppet, electric in either case, but that decision can wait until everything is working, plus I really should get an Impala airborne first.

Neil
"I'm your huckleberry, that's just my game"
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Carl
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Re: Two of a Kind

Post by Carl »

NeilMac wrote: 08 Feb 2019, 11:07 the Waltron Tx is a tiny thing, smaller even than the s/c button MacGregor, but it does have some depth to it. If holding with two hands it is kind of one at the top (on the rudder) and occasionally one on the bottom to save dropping it and to shift the throttle when needed.
That's exactly how I use my Waltron Mini 2, and is a lovely tx to hold and fly with :P
Carl

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STILL LEARNING
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NeilMac
Posts: 165
Joined: 04 Feb 2019, 22:07
Location: Nth Somerset

Re: Two of a Kind

Post by NeilMac »

Blimey! That was quick...

Thank you Robotbirds.
Stuff 2.JPG
Right, time to get busy.
stuff 5.JPG
"I'm your huckleberry, that's just my game"
NeilMac
Posts: 165
Joined: 04 Feb 2019, 22:07
Location: Nth Somerset

Re: Two of a Kind

Post by NeilMac »

Big thanks to Phil G for the encoder boards, each set up to suit the individual transmitter.

As the Digi 2 is already in bits, it is first in the queue, I now need to start gathering a few connectors as I am going to try and make this a 'plug in' installation for no other reason than 'cos I want to'.
All the bits 2.JPG
Last thing to buy are a couple of Lipo's, but I can get soldering in the meantime.
"I'm your huckleberry, that's just my game"
NeilMac
Posts: 165
Joined: 04 Feb 2019, 22:07
Location: Nth Somerset

Re: Two of a Kind

Post by NeilMac »

Final update of part one.

Finally I have all the parts and cables I want, so just a few solder joints and we are ready to go..... or not.

Switch on... no smoke, that's good, press a variety of tiny buttons in the correct order and binding is complete, now, lets get those servos buzzing......

My advice to anyone thinking about doing this kind of conversion, read Phil G's conversion document and once you've done that, do it again. I didn't, I skimmed, it is a bad habit picked up after years of dealing with long commercial contracts, and so I missed several vital bits of information... I had seen them, I even understood them, they just had not sunk in.

So, after rewiring the pot to encoder connections, I was confident again, nope. Ahh, calibrating the pots, yes of course. After several unsuccessful attempts I had a back and forth of e-mails with Phil G, who is a fine and patient chap. In the end I fully understood the channel allocations, plug positions etc and was ready to have another go at calibrating.... BINGO. Amazingly, the pile of wire and circuit boards on my desk was actually communicating commands which were being picked up and turned into motion, amazing.

Pretty it ain't, but it works.
On the bench.JPG
On the bench 2.JPG
All the bits 2.JPG
So now it was time to start getting things to fit back into the original enclosure. I am not a glue gun for everything fan, but in this instance it certainly is a handy tool. The bind button is installed lower down in the left hand side plate.
In the box.JPG
This is the clever bit, thank you Phil, you are a gentleman.
Encoder.JPG
And here it is ready to rock'n'roll, and just in time too as although the Digi 2.4 will ultimately control a Veron Impala, its first installation will be in a Precedent Hi-Fly which a friend of mine has given me.
Lookin good.JPG
Part 2 will commence after the weekend with the Waltron, I will try my best not to repeat any of the mistakes I made on the MacGregor.
"I'm your huckleberry, that's just my game"
NeilMac
Posts: 165
Joined: 04 Feb 2019, 22:07
Location: Nth Somerset

Re: Two of a Kind

Post by NeilMac »

Right, second part, the Waltron Mini 2.

Obviously the electronics side of things was a lot more straightforward, what was challenging was where on earth to fit all the gubbins, I know it has been done but a cursory look on google (and here) did not provide the pictures I wanted, but I did pinch one idea which was to replace the original circuit board with a blank board that I could use to secure 'stuff' to.

First job was to remove all the bits I did not intend to use. My one mistake here was to take out the original battery wiring. The guys at Waltron meant these wires to be a permanent fixture, wrapping the posts with the core before soldering, by the time I discovered what they had done I was already committed to my course of action.
Empty Box.JPG
Digging around in my bitsa box I found some veroboard, so that was pressed into action to take the Frsky hack board, binding button and Rx switch. The encoder board fits perfectly into the bottom of the enclosure and a couple of strips of double sided tape ensures that nothing touches the metalwork.

This is the initial layout.
First go.JPG
Next job was to test the encoder and calibrate the sticks... and this is where I once again had to stop and do some reading.

Having used a bind plug on D11 rather than try to keep a teeny tiny switch pressed while I stick waggle, I finished waggling, removed the plug and BEEP BEEP, BEEP BEEP... ohhherr. Switch off, switch on... BEEP BEEP.... Must be a low battery. While the Lipo was charging I once again read Phil's install instructions, as soon as I got to the words throttle lock a lightbulb went on and a quick check showed the throttle slider was half way up.

Once calibration was complete I bound the Tx and Rx together and plugged in a couple of servos. Throttle, perfect, rudder...erm, not so much. Lots of buzzing and jittering was all I got, switch off, think, reach to my right and pick up the can of Servisol Switch Cleaner, spray into rudder pot and waggle a good deal, wipe off excess and calibrate again. Bingo. As these pots are 40 to 50 years old it really is no surprise to find the tracks and wipers within have got a bit grubby, Servisol is amazing stuff, I have brought entire motorcycle wiring looms back to life with it and will be sure in the future to treat all pots to a dose before I convert the transmitters.

With everything sited the next job to do was install the antenna. I don't like altering things beyond reuse, but in this case the only way to make a neat job was to cut the bottom out of the plastic base unit. I slid it onto the antenna cable, screwed the cable onto the antenna itself, put a couple of dots of hot glue on the metal parts and shoved it all inside the base, once that was stuck I did the same again with the base to the case.

So, now it was time to put the back on and here we ran into problem No.2. The hack unit was sticking out too far, so as it was only held in place with a small square of double sided tape I pulled it off, moved it down, relocated the switch and had another go.
Second Go.JPG
This time the back fitted and with everything cased up another test was done and everything worked perfectly.
All done.JPG
Next job will be to replace the throttle servo with an esc, and then decide which model to build.

So, first two conversions done, I think my next one will be a 4 channel, a Waltron Clubman would be perfect, but it seems hens teeth are more plentiful so I may end up with a Skyleader, as these seem to come up for sale much more frequently... unless of course a MacGregor Digi IV shows up in the meantime.

HUGE thanks to Phil G, not just for supplying the encoders, but also for his help and advice when I got a bit lost.
"I'm your huckleberry, that's just my game"
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