Show Posts
Pages: 1 ... 3 4 [5] 6 7 ... 15
61  Using Arduino / General Electronics / Mystery magnetic sounder problem on: January 21, 2013, 11:31:18 am
I had a minor mishap at work today and I'm hoping you guys might be able to shed some light on it. I was doing something in work involving attaching wires to sounders - a simple job. Sounders in parallel at one end, hirose crimp connector at the other. For some reason, even though they continuity tested OK, they failed their functional test in which a signal is pumped in and the dB levels measured - they were far too quiet and some sounded crackly. We can't find any problems with the test gear itself, and it doesn't look like there's an issue with the brand new ones in the tube.

Can these things be damaged by cleaning with IPA after soldering? I'm wondering (and it is a bit of a long-shot but so far we can't figure out why they're buggered) if flux residue dissolved in the IPA has gone up inside the thing and hardened again, messing with the little diaphragm somehow. Any ideas on what to try? It'd be nice to rescue them and not have to re-do the entire lot. smiley
62  Using Arduino / Project Guidance / Re: Where to go from here :S on: January 18, 2013, 05:37:47 pm
If you've got a Mega, why use software serial? Don't you now have more hardware UARTs to use? If you have the peripherals on-chip, USE them! smiley Same goes for SPI too.
63  Using Arduino / Project Guidance / Re: Arduino and CMOS Camera Module on: January 18, 2013, 05:19:44 pm
Looks like it provides an analog video output (although I could be wrong here). I don't think an Arduino board is what you need here. Perhaps consider a USB capture device instead?
64  Using Arduino / General Electronics / Re: Soldering Hell on: January 09, 2013, 04:38:53 pm
At work, I use a 120W iron normally set to 320C, and leaded 60/40 solder. Gets up to temperature and transfers heat to the workpiece quickly, and with the occasional tip-change the same iron works for everything from soldering shielding tape over everything, doing wiring looms, connectors and sticking stuff on PCBs. I'm hardly an expert (although I rarely diddle anything up so badly it can't be re-done), but the golden rules for me are:

1) Plenty of flux
2) Clean EVERYTHING with plenty of IPA before working on it
3) Keep that tip tinned and shiny
4) Use the brass brillo pad things instead of a wet sponge smiley-wink

Lead-free solder is horrible, nobody I work with likes it, and thankfully we're not required to use it due to an exemption. I'd NEVER use the stuff at home either. Just wash your hands after handling it and there's no real harm... although good luck finding it at Maplin these days!

65  Development / Other Hardware Development / Re: Review of siplified Version of Arduino DUE on: January 09, 2013, 12:26:49 pm
You know, I keep forgetting that stuff even exists! I really need to put in a requisition for some at work... Thanks for the reminder!
66  Development / Other Hardware Development / Re: Review of siplified Version of Arduino DUE on: January 05, 2013, 02:07:03 pm
Good luck desoldering that main SAM chip smiley-wink Wouldn't want to be you. All the other parts are easy with a half-decent hot air rig and vacuum tweezers, but removing million-pin QFP's is not my idea of fun.
67  Using Arduino / General Electronics / Re: IRF740 MOSFET on: January 05, 2013, 01:57:24 pm
I think the gate-to-ground resistor is there to pull the gate low and keep it there unless something drives it high on purpose, to prevent accidental or unwanted switching. Could be wrong... but I seem to recall that's what it does.
68  Using Arduino / Project Guidance / Re: Beginner Question on: January 05, 2013, 07:21:43 am
You'll probably need to fit an external 16mhz crystal and a couple of 22pf caps. Taken straight from an UNO, the fuses on the chip are going to be set for an external crystal which you'll need to provide if you want it to work. Have a look around for some arduino to breadboard circuit diagrams and you'll get the idea.

Also, I would consider slightly more beefy batteries. I can't see a couple of coin cells lasting very long if they power it at all... but that does depend on the power requirements of your project, which I can't guess at without measuring it smiley
69  Using Arduino / Project Guidance / Re: Receive Video through the USB and transmit it via bluetooth on: January 04, 2013, 03:31:21 pm
I very much doubt it, given the limited resources of the chip.
70  Using Arduino / General Electronics / Re: How to suppress terrible noise from MAX7219? on: January 01, 2013, 12:49:07 pm
I checked his other posts and they were the same sort of shit. So I reported them. smiley
71  Using Arduino / Project Guidance / Re: [Video] Thats why i had so many questions !! Thanks , great people,great forum ! on: December 28, 2012, 10:25:41 am
Nice bit of wire-porn there smiley-grin
72  Using Arduino / Displays / Re: display on: December 14, 2012, 11:37:23 am
Buy a 4-line (or graphic) LCD, or change the requirements of your project smiley Without some serious messing around I don't think there's any way to get a 2-line LCD to look like it's displaying three lines of text.
73  Using Arduino / Project Guidance / Re: Arduino testing its own power source ? on: December 01, 2012, 11:57:37 am
http://arduino.cc/en/Reference/AnalogReference

Couldn't you also use this?
74  Using Arduino / Project Guidance / Re: Getting 640x480 images from camera modules at 1FPS on: November 27, 2012, 12:24:25 pm
Isn't the rasp-pi actually cheaper than a high-end (genuine) Arduino board? If cost is a huge factor here I doubt changing over to the pi would make an enormous difference. And they're tiny smiley-grin As long as you can learn how to do what you want on that platform, you can't lose.
75  Using Arduino / Displays / Re: Displays from printers etc. on: November 22, 2012, 02:39:02 pm
You just know... the day after you throw it away, someone will write a decent library for exactly that part.
Pages: 1 ... 3 4 [5] 6 7 ... 15