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goc30

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Joined: 12/04/2017
Location: France
Posts: 435

Posted: 06:17am 18 May 2018

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Thanks for the correction, I forgot.
Regarding the driver circuit, we do not need such a radiator or these big connectors, but it's still a bit complicated

Grogster

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Joined: 31/12/2012
Location: New Zealand
Posts: 9751

Posted: 12:24am 22 May 2018

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The decoder PCB's have arrived, and I am very happy with the final size. I have yet to build one, but I hope to do that sometime this week and have a play around with some code on the MM at the heart of it.

The decoder board is designed to interface with an HC12, which is why one is shown in the photos with it. The board was not designed to stack with the HC12, as that might have made the overall arrangement too thick, so the decoder and HC12 will be joined with short linking wires - I will upload more photos once I have one assembled.

I plan to use the clone HC12's for this project, as although they are off frequency, they will be fine for this kind of thing.

Smoke makes things work. When the smoke gets out, it stops!

Grogster

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Posted: 11:03pm 07 Jun 2018

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Finally got a chance to assemble a decoder and the programmer boards. Both worked on the first attempt, which was nice.

I have just to write some code to control a motor with PWM, controlled by an HC12.
To be continued...

Smoke makes things work. When the smoke gets out, it stops!

Chopperp

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Joined: 03/01/2018
Location: Australia
Posts: 1106

Posted: 03:02am 08 Jun 2018

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Hi Groggs,

Just a quick PCB question.

I noticed that you have had all the copper apart from the tracks etched on these boards, but on most of the others you do, most of the copper is left with the etching just around the tracks.

I was wondering why you didn't do that for these boards? Just asking.

ChopperP

Grogster

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Posted: 05:48am 08 Jun 2018

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When I leave the ground-plane in place, which I usually do, I use that ground-plane as a ground connection for circuit ground. On this PCB, it was so small, that whatever GP was left over, was not connected to anything anyway, so I just routed a ground track for this board instead. IE: It would have been just about impossible to connect all the broken-up GP together on this size PCB and still keeping to two layer. And it was also just a personal choice kinda thing also to some extent.

Smoke makes things work. When the smoke gets out, it stops!

Chopperp

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Joined: 03/01/2018
Location: Australia
Posts: 1106

Posted: 06:29am 08 Jun 2018

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Thanks Groggs,

I thought that was the case. I haven't delved deep enough into actual PCB software or had the need to worry about ground planes.

ChopperP

Revlac

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Joined: 31/12/2016
Location: Australia
Posts: 1204

Posted: 09:16am 08 Jun 2018

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Thats looking good Grogster.
Have been watching for a bit, Have read that Hornby use there own type of DCC system.
We had a Hornby Mallard live steam loco running on the bench years ago, much fun,

however the controller took a fair bit of practice and patients getting use to it.
It used a series of pulses to get it moving, and other things.
Do you want to know what happened when someone els has a go at it without prior practice.?

Cheers Aaron
Off The Grid

Grogster

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Posted: 09:40pm 08 Jun 2018

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By all means......

Smoke makes things work. When the smoke gets out, it stops!

Revlac

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Joined: 31/12/2016
Location: Australia
Posts: 1204

Posted: 11:07pm 08 Jun 2018

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Well after I had a Run with it I parked the loco just at end of the bench coming on to the straight bit of track.
Give the Old Man the controller, first he give it a few pulse's to start it off... nothing happened, so the next idea was to hold the throttle lever on for a moment and that got it going... I mean REALLY Got Going, that thing could fly....could not take the bend at the end and flew about 6 feet off the end of the table to the ground.

The wheels and rods where still going so fast it was just a blur to see.
Quite spectacular to watch, but it was still a bugger picking up all the pieces. We did get it running again though.

So I can see a reason to have good steady controls on these things.
went back to using PWM speed control for a bit on the G scale layout, they are big but more to put things in them.
I know some people criticize G scale for there own reasons, seen holes in walls of some houses for the track and loco to run through, All is forgiven when you see a train coming from the kitchen with a load of beer.

Cheers Aaron
Off The Grid

Grogster

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Posted: 12:08am 09 Jun 2018

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Ha,ha!

I plan to allow for a maximum throttle setting and emergency shut-down in the controller, which will all be touch-screen based on a MM plus. Simulated inertia on forward and reverse can be switched off or on on the LCD controls. Up to one thousand locomotives will be supported - I doubt anyone should need more then that in one layout!

Smoke makes things work. When the smoke gets out, it stops!

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