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[wombat]

Not sure where to put this, but here is the latest project...

Little magic box to test servos and exercise them to test out the linkages and attached mechanisms.

The PCB was done with "Press'n'peel" as I foolishly got rid of my UV box when I moved four years ago. Needs getting to grips with, but has promise. Need to get the design rules sorted out.

The unit uses a PIC microcontroller programmed in C using freebie tools. I will put up the source code onto my web-sit over the next few days along with schematics and layouts.

As much as anything this was a feasibility study to see how difficult it is. Overall cost for the box was about £20 including the little box thing with the rubber bumper.

Wom

[OMK]

I must say that's an excellent little project, Mr. Wom. I'm not sure, but is that a couple of rotary encoders I see there? (Nice touch). Even the enclosure is pretty sleek.
I'm not sure what s/w you're using to draw the front panel decal, but whatever it is, I like what you've done.

I also read with interest that you're using Press 'n' Peel. For my sins I can only achieve approx 30% success using that particular medium. You seem to have got it nailed. So are there any not-so-obvious pitfalls one should be aware of?

Regarding the PIC s/w, Dave FLJ says that you're the man to know regarding writing code in C.
Would love to pick your brains about that. Is it okay if I fire a few questions your way?

Meantime, can I bend your ear with these?...

1) What is the job of that PP3 batt. connector? (The PP3 and the Ni-Cad is throwing me.)
2) You mentioned your website. Can you post the URL?


Excellent stuff.
Thanks.

[red]

Anyone not up to making there own pcb, Action do one that works very well .

'R/C MASTER' SUPER SERVO TEST AND R/C CALIBRATION TEST EQUIPMENT

Fred

[wombat]

Hi PMK,

Sorry, but no, they are not rotary encoders but cheapo 9mm pots - the PIC16F690  has an on-board ADC with 10 input channels. Using a pot across the rails with the supply used as a reference gives you a handy system that uses a single I/O whereas a rotary encoder would need two. Also with an encoder you need to monitor constantly for changes, the ADC can be read as and when. Not big problems. Also I wanted a test bed for checking multiple ADC reads.

Yes, I have had trouble with press'n'peel - so far I reckon it is probably good for 12 thou tracks on a 25 thou grid. The trick seems to be to allow a lot of heat - for that board, I ironed it for a good five minutes. You need to watch for the pattern becoming a good strong black on the back of the film. Saying that it still needs a lot of work. Dammit I wish I'd kept my UV box.

The front panel was drawn using Free2Design and printed on a4 sticky paper - this was then fastened to the front of the box. Advantage of this is that the glue holds the buttons to the front so it behaves like a membrane. Only thing I need now is to put some clear sticky-back plastic over the front to prevent wear.

As regards C programming - I have done a certain amount, feel free to pick away via e-mail or PM  - I will also put up a URL to the web-site once I have done a couple of updates tonight. That has a blog on it

The PP3 connector is inside the box - this is used to feed the board via a 7805. As an alternative if you need a little more go, you can use an external NiMH pack - for example if you are driving a fiarly meaty servo that would suck a PP3 dry. You can also power the thing through the servo socket so you could exploit a BEC on an ESC if you are driveline testing.

Hi Fred,
The unit isn't as full-featured as the ACTion system - but its prime purpose was not to produce an all-singing all-dancing tester but a bit of kit to use on boat builds and also to act as a test bed for a few ideas. For serious use for anyone who doesn't want ot muck about with the ins and outs of PICs, the ACTIon kit is a better choice - but I wanted to play!

Wom