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1  Community / Bar Sport / Re: Time to get designing. on: April 01, 2014, 06:24:11 pm
Quebec has their own rules for contests, which aren't quite compatible with the rest of the world:
2  Community / Bar Sport / Re: Calls "from windows" about "online hackers inside your computer". on: March 06, 2014, 06:42:29 pm
Seagate was the only company that offered a 5 year warranty. They stopped that practice during the flood, just like everyone else though. Now  all the companies only offer a 1 year warranty.

The last time I bought a WD Red, it had a 3-year warranty. No idea if that has any meaning these days (especially if you put it in a machine you build rather than a consumer NAS... I suspect their response would be "sorry, you didn't use it according to our spec".)
3  Community / Bar Sport / Re: Problen with ds102 oscilloscope on: February 05, 2014, 05:48:36 pm
I'd bet the USB cable for the oscilloscope has a Prolific PL2303 clone chipset. Prolific got tired of it and their new drivers detect the clone and disable it.

Here's some useful info:

If the USB cable isn't a regular serial device on XP, then this probably won't work - you'll need to find a Win7 64bit driver for your oscilloscope.
4  Using Arduino / General Electronics / Re: Help with CANbus Data logging on: January 14, 2014, 05:46:57 pm
Not sure why you can't use Arduino? You might want to look at:
5  Using Arduino / General Electronics / Re: What kind of connector is here? on: January 10, 2014, 05:42:44 pm
It's still hard to tell from your photo what the connector is. If it's a Wifi card, maybe it's mini PCI or mini PCI-E?
6  Using Arduino / Microcontrollers / Re: Attiny85 programming failing - Invalid device signature on: December 20, 2013, 02:03:20 pm

The usual culprits...

* Wiring
* Auto-reset not disabled
* Wrong board selected
* Buggy ArduinoISP sketch

Enabling verbose output usually reveals which.

For the benefit of future searchers, I'll also add that I've had an Attiny85 report "Device signature = 0x000000" after I walked across a polyester carpet with the device in my hand (sigh). Apparently, zapping the device with static electricity can sometimes cause it to report a bad signature. Switching to a new Attiny85 resolved my problem.
7  Using Arduino / General Electronics / Re: 5V to 12V level convertion ? on: November 15, 2013, 02:44:06 pm
There's no way to use a pin to drive the pump. Even in an ideal world, 200 mA at 12V = 480 mA at 5V, and there's no way a single pin could do that.

You could use a pin to switch a FET / relay, though. Then you could use a boost converter to raise the supply voltage from 5V to 12V - they're available commercially or you could make one:

It might be easier to start with a 12V supply and regulate it down to 5V for the Arduino instead.
8  Community / Website and Forum / Re: reboot: feedback and comments on: October 02, 2013, 06:43:19 pm
On Firefox 17.0.9 / Win XP, I see nothing except a blue banner unless I type a character in the search box at the upper right.

(This is true of both and

- actually, I'll second Jantje : the header under Firefox is just huge. I can scroll down to see the text, but entering a space in the search box shrinks the header.
9  Using Arduino / Programming Questions / Re: How to return a char from a function on: September 19, 2013, 02:06:58 pm
char lat[15] is a string (roughly equivalent to char* lat) - it's a pointer to a place in memory. char is a single value between 0-255. You can't assume there will be an automatic conversion.
10  Using Arduino / Project Guidance / Re: Replicating an RF remote signal on: August 23, 2013, 06:54:18 pm
If you're interested in going seriously over the top, maybe investigate using a DVB SDR (software-defined radio). You'd be able to sample the spectrum around 315 MHz using one of those for a lot cheaper than a scope.

A few links:

I'm only half joking...
11  Community / Bar Sport / Re: SOLVED:Anybody own the MPJA 9616PS / Circuit Specialists CSI3003SM power supply? on: August 20, 2013, 01:05:59 am
Thanks, I'll give those ideas a try. I've also noticed a suspiciously bulging capacitor pretty close to R6 - that might also have suffered in the event. Once I get a replacement, I'll see if that helps things.
12  Community / Bar Sport / Re: Anybody own the MPJA 9616PS / Circuit Specialists CSI3003SM power supply? on: August 17, 2013, 02:50:27 pm
Today I replaced the existing lead in there (which was 20 gauge wire) with some 22 gauge hookup wire I had on hand. So far so good - the voltage seems close.

I don't think I quite trust the current anymore... at rest the meter's reading about 0.2 A rather than 0. I'm not sure if that has to do with my choice of R6 or with something else I stressed when I pushed 13.8 V through there backwards.

At any rate, I have a power supply again, even if it's a little degraded. Thanks to everyone for your thoughts/ideas!
13  Community / Bar Sport / Re: Anybody own the MPJA 9616PS / Circuit Specialists CSI3003SM power supply? on: August 13, 2013, 01:28:32 pm
Hmm... measuring the resistance of the wire I've got left doesn't yield much info either. I guess I'll just have to grab some wire, stuff it in there and see what happens.
14  Using Arduino / Project Guidance / Re: How to build an suitable RF antenna for Receiver/Transmitter? on: August 12, 2013, 12:50:04 am
Most of the 315 MHz antennas I can find are either "rubber ducky" whip antennas or antennas with a magnetic base. In either case, there's a ground plane (typically an automobile roof underneath the magnetic base, or a handheld radio and the user's hand underneath the rubber ducky - not the best of ground planes, but it's a ground plane  smiley )

Coax loss can indeed be dramatic, especially with certain types of coax. It's hard to tell what you're using, but if it's RG-58 coax, then it will lose somewhere between 7.3 dB and 11.2 dB every 30 m or so. That equates to a loss of about 58% of the signal in the worst case. Some types of coax are better than others at high frequencies. Here are some useful charts if you're trying to decide what coax to use:

It should be fine to connect the ground of the antenna to the circuit ground.
15  Community / Bar Sport / Re: Anybody own the MPJA 9616PS power supply? on: August 12, 2013, 12:08:09 am
Thanks, Osgeld! I'll modify the title of this post for posterity, and look forward to hearing what your value for R6 is. Hopefully it's the same for the CSI3003SM as the CSI3005SM - at the very least, now I know a place to pick up a replacement supply cheaper!

Thanks again!
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