Search found 332 matches
- Mon Sep 13, 2010 7:42 pm
- Forum: General Discussion
- Topic: Can someone help with a DIY project?
- Replies: 10
- Views: 4992
Re: Can someone help with a DIY project?
Is this a serious plea for help or a veiled act of self-promotion?
- Fri Aug 27, 2010 8:09 pm
- Forum: General Discussion
- Topic: 4n35 collector wired to TIP31c base?
- Replies: 7
- Views: 3917
Re: 4n35 collector wired to TIP31c base?
Dale,
Here's what I'm up to:
Schematic
I'm pretty sure an ON led is what starts current flowing, no?
Here's what I'm up to:
Schematic
I'm pretty sure an ON led is what starts current flowing, no?
- Thu Aug 26, 2010 12:41 pm
- Forum: General Discussion
- Topic: 4n35 collector wired to TIP31c base?
- Replies: 7
- Views: 3917
Re: 4n35 collector wired to TIP31c base?
I'm using four of them to drive a stepper.
The stepper coils are 2.5 ohms. Since my PS is 13.5v, it appears that I might be exceeding Ic (5A). Does that mean (theoretically) that the base of the TIP31 is drawing the full 1A?
The stepper coils are 2.5 ohms. Since my PS is 13.5v, it appears that I might be exceeding Ic (5A). Does that mean (theoretically) that the base of the TIP31 is drawing the full 1A?
- Thu Aug 26, 2010 10:49 am
- Forum: General Discussion
- Topic: 4n35 collector wired to TIP31c base?
- Replies: 7
- Views: 3917
4n35 collector wired to TIP31c base?
Noob question here: I found a circuit while Googling that has me connecting a 4n35 collector to a TIP31c base. If I'm reading the data sheets correctly, 4n35 Ic has a max rating of 100mA and TIP31c IB can draw up to 1 amp. There should be a 2N2222 or something between, correct? The fact that I haven...
- Sun Aug 15, 2010 6:21 pm
- Forum: General Discussion
- Topic: Controlling relay via the web
- Replies: 7
- Views: 3503
Re: Controlling relay via the web
Browse your local thrift stores for a WRT54G-flavor router. I've purchased one for as little as $5. There are a number of posts about powering a relay with one at http://www.openwrt.org.
- Thu Jun 17, 2010 5:31 pm
- Forum: General Discussion
- Topic: [OT] Career advice
- Replies: 13
- Views: 5290
Re: [OT] Career advice
psycho, It would be irresponsible to discourage you from getting a degree, I highly recommend one. But while you're working on one, here are some ideas: I work with plenty of people in IT that don't have a degree at all or do have one in something unrelated. The VP of our division at my last day gig...
- Wed Mar 17, 2010 9:15 pm
- Forum: Computer Programming
- Topic: Web Server on Win98SE?
- Replies: 6
- Views: 5656
Re: Web Server on Win98SE?
CeaSaR, I'm with desy. Any MS web server product that would run on a Win98se machine will become a spammer's paradise before you know it. Soon thereafter, spam filters will block any calls to your site for fear of downloading a worm. You'd be hosting a slave on a botnet along with your web content t...
- Tue Mar 16, 2010 4:18 pm
- Forum: General Discussion
- Topic: Town flood, power outage, backup power ideas?
- Replies: 21
- Views: 7924
Re: Town flood, power outage, backup power ideas?
MrAl, sghioto's suggestion in hard to beat. Those Honda EU series gennys are whisper quiet and under $1k. You should certainly consider one as an option. I've run a borrowed Honda EU1000i for a week (12hrs a day) on 10 gallons of gas. Here's my system break down: 8 12v AGM deep-cycle batteries - $12...
- Tue Mar 16, 2010 11:07 am
- Forum: General Discussion
- Topic: Town flood, power outage, backup power ideas?
- Replies: 21
- Views: 7924
Re: Town flood, power outage, backup power ideas?
MrAl, The power projects you've helped me with go to provide electricity for our place in the Sierras where PG&E hasn't installed power poles. Because I'm worried about theft, I've built a trailer that carries my 8 group 31 12v batteries back and forth between our house here in the SF Bay and th...
- Sun Mar 07, 2010 5:30 pm
- Forum: Computer Programming
- Topic: Sorting Excel 203
- Replies: 6
- Views: 6019
Re: Sorting Excel 203
Josey, Not sure if it's exactly the answer you want, but I often run into situations where I need to establish a row sort order in Excel. In one of your columns, place the number 1 in row 1. In row 2 of the same column, type =1+ and click on the cell you placed the number 1 in. Starting with the cel...
- Sat Feb 27, 2010 7:46 pm
- Forum: General Discussion
- Topic: is the gate open or closed
- Replies: 18
- Views: 9360
Re: is the gate open or closed
Anything with a transmitter would be relatively power-hungry. If my math is right, the device sambuchi linked to draws ~60mah, so a 9v battery would only power it for 10 hours. You would therefore need something more substantial and plan to have some charging mechanism in place (solar or two batteri...
- Fri Feb 26, 2010 9:34 am
- Forum: General Discussion
- Topic: The bloom of the Bloom fuel-electric cell...
- Replies: 10
- Views: 5790
Re: The bloom of the Bloom fuel-electric cell...
sofaspud, I found the blog post you linked to interesting. I have similar concerns. While I think it would be pretty nice to bring on-demand power generation closer to where it is needed, until such generators approach the efficiency of those used in utilities' power plants burning the same fuel, su...
- Wed Feb 24, 2010 8:40 pm
- Forum: General Discussion
- Topic: Cellular (800Mhz) antennas/boosters?
- Replies: 22
- Views: 12140
Re: Cellular (800Mhz) antennas/boosters?
Any coax cable recommendations? A bit of Google searching has shown RG8 and LMR400e as options, but I know little about what makes one cable type better than another. I was considering using a 20ft pole initially and perhaps going as high as 100ft (provided I can find a decent tower on Craigslist fo...
- Thu Jan 28, 2010 9:02 am
- Forum: Computer Programming
- Topic: What is the best computer virus protection?
- Replies: 17
- Views: 9669
Re: What is the best computer virus protection?
This thread was started by a spammer. See the link at the end of his post?
- Fri Jan 22, 2010 3:30 pm
- Forum: Computer Programming
- Topic: emachines computers
- Replies: 7
- Views: 4495
Re: emachines computers
I owned an eMachine about 5 years ago for a few weeks. The PC was fine, but their support/warranty strategy was terrible. When the CDRom stopped working, their only solution was to ask me to ship the entire machine (at my own expense) to them for service with a 3-week turnaround. When I asked them t...