Search found 236 matches

by chessman
Thu Apr 24, 2003 3:12 pm
Forum: General Discussion
Topic: Senior project idea
Replies: 11
Views: 2854

Re: Senior project idea

I would provide a schematic, but I don't have one made and I don't have the time to make it.<p> I'll be activating anywhere from 1 to 8 leds at a time, in a column. This will be dependent on what the sign is displaying.<p>They're just set up in a matrix of 8 rows by 32 columns, and the columns will ...
by chessman
Thu Apr 24, 2003 9:57 am
Forum: General Discussion
Topic: DON'T POST LONG URLs
Replies: 13
Views: 3456

Re: DON'T POST LONG URLs

I'm interested in your sneaky code too........
by chessman
Thu Apr 24, 2003 9:34 am
Forum: General Discussion
Topic: PIC crystals
Replies: 2
Views: 1320

Re: PIC crystals

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by bodgy: <p>The short answer is yes. Actually the long answer wouldn't be much longer than the short one. :p <p> Colin <hr></blockquote><p>I'll give the long answer, and you'll see how much longer it...
by chessman
Thu Apr 24, 2003 9:30 am
Forum: General Discussion
Topic: 100 ohm resistors
Replies: 4
Views: 1502

Re: 100 ohm resistors

Haha yeah thanks, but that'd be too big for my project.
by chessman
Thu Apr 24, 2003 9:26 am
Forum: General Discussion
Topic: Senior project idea
Replies: 11
Views: 2854

Re: Senior project idea

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by L. Daniel Rosa: If you're multiplexing for "column at once" (8 LEDs), then you only need 8 CCSs to regulate the current. If you try to activate only one LED at a time, it'll be too dim (I spoke to ...
by chessman
Wed Apr 23, 2003 8:00 pm
Forum: General Discussion
Topic: 100 ohm resistors
Replies: 4
Views: 1502

100 ohm resistors

Hey guys, I just realized I need some 100 ohm resistors for my project....35 of em...anyone think I can bum em off you?<p>I hate to ask but I have already spent too much on the project, I can't spend even a penny more :(
by chessman
Wed Apr 23, 2003 7:58 pm
Forum: General Discussion
Topic: Senior project idea
Replies: 11
Views: 2854

Re: Senior project idea

I'm planning on using them as a current amplifier so I can run the LEDs off a single 100 ohm resistor.<p>Ack! Is that one BJT and diode for each LED?<p>I guess that's kinda what I was expecting but it really sucks...I don't know if I can handle that much wiring in the time I have :eek: <p>I'll just ...
by chessman
Wed Apr 23, 2003 5:49 pm
Forum: General Discussion
Topic: Senior project idea
Replies: 11
Views: 2854

Senior project idea

Hey guys, I'm almost done with the design of my project.<p>Basically I'm creating an animated LED readerboard, so it's an array of 8 x 32 LEDS.<p>I'm using 74HC595 shift registers for the multiplexing. They have a max current of 35mA, and that's way too low for my brightness level of LED (I'm gonna ...
by chessman
Wed Apr 23, 2003 5:40 pm
Forum: General Discussion
Topic: OK , so i have nothing better to do !
Replies: 13
Views: 3722

Re: OK , so i have nothing better to do !

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by Jolly Roger: dacflyer <p>I like your idea. But to make it more interesting you could "radomly" place the LEDs on the front panel. Thus they don't simply go in a 123 sequence. Then you can tell peop...
by chessman
Thu Apr 10, 2003 9:47 am
Forum: General Discussion
Topic: DON'T POST LONG URLs
Replies: 13
Views: 3456

Re: DON'T POST LONG URLs

I always post the actual URLs because some people have trouble clicking on links. I always like to see full URLs in posts because sometimes I copy and paste them, and some people don't know you can right click and then hit copy shortcut.
by chessman
Wed Apr 09, 2003 8:37 am
Forum: General Discussion
Topic: Speaker Building
Replies: 9
Views: 2440

Re: Speaker Building

If you don't care about sound quality that much, you could use a piezo disk, and attach it to a horn. That's how "tweeters" are implemented in those car audio boxes and other inexpensive applications. <p>As for an "actual" tweeter, you're probably not going to be able to build one. This is because o...
by chessman
Mon Apr 07, 2003 12:31 pm
Forum: General Discussion
Topic: Urgently need PIC code!
Replies: 4
Views: 1348

Re: Urgently need PIC code!

Unfortunately, no, that does not work.<p>The pulses I need to output need to be a fast as possible.<p>Just a macro that will do this is great.
by chessman
Mon Apr 07, 2003 10:16 am
Forum: General Discussion
Topic: Urgently need PIC code!
Replies: 4
Views: 1348

Urgently need PIC code!

Hey guys, I'm working on my senior project, and I need some code snippets...REALLY BAD!!!<p>Okay, I need a macro that will output pulses to a shift register, and the count of the pulses will be controlled by a single variable byte.<p>I need this URGENTLY!<p>Processor is 16F877<p>Thanks so much, I ap...
by chessman
Sun Apr 06, 2003 8:18 pm
Forum: General Discussion
Topic: Speaker Building
Replies: 9
Views: 2440

Re: Speaker Building

All I have to say, is you're insane ;) <p>You have made sure that you're wire is enamled yes? You don't want your coil to turn into one thick piece of wire.<p>I would have to say you might want to just buy a good voice coil, frame, and a cone or two. Then you could piece together you're own "profess...
by chessman
Thu Apr 03, 2003 7:41 pm
Forum: General Discussion
Topic: CCFT Backlight inverter schematic
Replies: 2
Views: 1022

CCFT Backlight inverter schematic

Hey guys, I have an OPTREX DMF-50840 LCD module, it's a nice 320x240 unit and has a CCFT backlight.<p>I need a quick and dirty inverter that will give me 340VAC to go into the CCFT, I don't know the frequency required.<p>EDIT: I know the frequency now, it's 30kHz. Iout is 10mA. <p>Actually, honestly...