Search found 125 matches

by Tommy volts
Wed Jan 05, 2005 7:53 am
Forum: General Discussion
Topic: Digital thermostats
Replies: 7
Views: 1845

Re: Digital thermostats

perfectbite,<p>The kindest thing you could do for her would be to install a simple digital thermostat. You could drop in on her from time to time to adjust the settings.
by Tommy volts
Mon Nov 29, 2004 11:39 am
Forum: General Discussion
Topic: Universal Shift Register 74LS194
Replies: 2
Views: 791

Re: Universal Shift Register 74LS194

Ron, <p>I believe you. <p>Thank you for your quick response.
by Tommy volts
Mon Nov 29, 2004 8:22 am
Forum: General Discussion
Topic: Universal Shift Register 74LS194
Replies: 2
Views: 791

Universal Shift Register 74LS194

I am building a pushbutton input 4 bit serial-in parallel-out shift register. I can use Four D flip-flops with synchronous clock pulse using a 0.3 hz clock(50% duty cycle 555 timer w/ LED on output already built).<p>Holding the push button down as the timer blinks from on to off (negative edge trigg...
by Tommy volts
Mon Oct 11, 2004 2:13 pm
Forum: General Discussion
Topic: LM34 to computer
Replies: 15
Views: 4071

Re: LM34 to computer

Mike,<p>I built a very simple serial port I/O interface between a thermistor and 486 PC. I wrote the program in BASIC. A couple of resistors, a transistor, and a thermistor was all it took. Total cost was about $5.<p>Let me know if you are interseted.
by Tommy volts
Thu Aug 26, 2004 9:02 am
Forum: General Discussion
Topic: 12 Button Keypad (Matrix Encoded)
Replies: 6
Views: 1605

Re: 12 Button Keypad (Matrix Encoded)

Stephen,<p>The Fairchild MM74C923 data sheet has everything I need to know. After I build the encoder I will post the results.<p>thank you.<p>"Why?...because its there"
by Tommy volts
Wed Aug 25, 2004 3:06 pm
Forum: General Discussion
Topic: 12 Button Keypad (Matrix Encoded)
Replies: 6
Views: 1605

Re: 12 Button Keypad (Matrix Encoded)

Stephen,<p>The three or 4 counter IC's sound like a great way to go, I'd really rather avoid having to program a microcontroller.Do you know where I might find a schematic design for this?
by Tommy volts
Mon Aug 23, 2004 9:00 am
Forum: General Discussion
Topic: 12 Button Keypad (Matrix Encoded)
Replies: 6
Views: 1605

Re: 12 Button Keypad (Matrix Encoded)

poseidonx,<p>Maybe the only way to use this keypad is with a microcontroller. Thank you for the link to the notes for using the PIC 16C54 for the interface. I will try using the PIC 16F84 for the interface( I built a programmer for the PIC 16F84 several years ago).
by Tommy volts
Fri Aug 20, 2004 10:07 am
Forum: General Discussion
Topic: 12 Button Keypad (Matrix Encoded)
Replies: 6
Views: 1605

12 Button Keypad (Matrix Encoded)

While getting some stuff I needed online from All Electronics i also bought a 12 Button Matrix Encoded Keypad (about $5). A very simple keypad.<p>The problem is that it has 12 buttons but only 7 pins (7 pin header). I now know that the keypad is designed for a microcontroller (for example the EDE114...
by Tommy volts
Fri Aug 13, 2004 8:06 am
Forum: General Discussion
Topic: 12C509 programming
Replies: 23
Views: 4563

Re: 12C509 programming

dacflyer,<p>When you get it all figured out and built please let me know how you did it. I have been programming 16 pin microcontollers for years and didn't know there were 8 pin mcus easily and cheaply available. <p>I use a programmer I built myself and MPLAB(free) for my assembler howver 16 pin mc...
by Tommy volts
Mon Aug 09, 2004 8:37 am
Forum: General Discussion
Topic: wrong place for cap?
Replies: 8
Views: 1885

Re: wrong place for cap?

Jolly Roger,<p>That is a nice FSM design project. What is the frequency range? I may build this.<p>
Why? "because it's there"
by Tommy volts
Mon Aug 09, 2004 7:49 am
Forum: General Discussion
Topic: RS-232 control of light bulb
Replies: 10
Views: 2181

Re: RS-232 control of light bulb

petemig,<p>Are you still interested in RS-232 I/O relay control articles by Ray Green?
by Tommy volts
Tue Jul 06, 2004 9:25 am
Forum: General Discussion
Topic: RS-232 control of light bulb
Replies: 10
Views: 2181

Re: RS-232 control of light bulb

fro66y,<p>I built an I/O system that plugs into the DB-9 serial port. It controls up to 3 mechanical relays. The code (written in QBASIC) and design I got from an article by Ray Green in N&V.<p>It works great. The total cost was about $5.<p>If youre interested let me know and I will hunt thru my sta...
by Tommy volts
Mon Jun 28, 2004 12:27 pm
Forum: General Discussion
Topic: Temp. circuit on page 66 of July N&V
Replies: 11
Views: 1982

Re: Temp. circuit on page 66 of July N&V

HP,<p>That is a nice schematic. How did you get it on your post?<p>I think you must have put the drawing on a website and then posted it as a URL with a UBB code? <p>Ive tried to paste in schematics directly but have never been able to do it.
by Tommy volts
Mon Jun 21, 2004 8:25 am
Forum: Computer Programming
Topic: Free Not-For-Resale Copy of Visual Basic .NET 2003 Stand
Replies: 26
Views: 14912

Re: Free Not-For-Resale Copy of Visual Basic .NET 2003 Stand

Sorry to interupt, but what does the ".net" mean? I searched VB.net and it appears to be simply the next version of VB after VB6. But then I believe I stumbled on alot of other ".net" suffixes on other programs.<p>I am guessing that ".net" means that they have revised the language to better interact...
by Tommy volts
Mon Jun 21, 2004 7:53 am
Forum: Robotics
Topic: Learning about Robotics
Replies: 7
Views: 3329

Re: Learning about Robotics

Will,<p>It is the $17.95 kit (see link below). Have fun, it's a great kit!!<p>Microcontroller Kit