Search found 99 matches

by wd5gnr
Sun Jan 14, 2007 10:26 am
Forum: General Discussion
Topic: Ham radio question
Replies: 6
Views: 1454

I don't think that's true. The rules used to be very strict about no business related communications. Although the rules have been clarified in a relaxed way in 1993, I don't recall them being removed. So if two hams are talking about their jobs or ordering pizza over a phone patch, that's probably ...
by wd5gnr
Wed Jan 03, 2007 5:55 am
Forum: General Discussion
Topic: Building your own CPU from TTL chips
Replies: 42
Views: 20043

I'd second the notion of an FPGA project to save wear and tear on soldering and wirewrapping. I particularly like the Spartan 3 Starter Board from Digilent. If you buy it from Xilinx directly, you get a free CPLD board (or at least you did last time I bought one). On the other hand, if you buy it di...
by wd5gnr
Tue Oct 31, 2006 3:53 pm
Forum: General Discussion
Topic: Transistor Logic inverting PIC UART input??
Replies: 3
Views: 1548

Why a 4.7K resistor in the base?

Assume you have 5V on the base resistor on one side and .7V clamped from the BE junction on the other side. That's 4.3V.

4.3/4700 = 915uA

Drive that transistor into saturation!

A 470 ohm resistor, for example would give you around 10mA.
by wd5gnr
Fri Oct 27, 2006 5:34 pm
Forum: General Discussion
Topic: electronic workbenches
Replies: 3
Views: 1211

I did an article about SwitcherCAD in N&V a while back. It will do digital sort of. There is also a very active Yahoo group for it. If you want to see something really cool, swing over to http://falstad.com/circuit/ with a Java-enabled browser. Not only is this really cool, but you can make your own...
by wd5gnr
Wed Apr 06, 2005 8:48 pm
Forum: General Discussion
Topic: connect keyboard to serial port
Replies: 18
Views: 3670

Re: connect keyboard to serial port

I know you want to build it yourself, but just for the record: coprocessor. There is also a link to a board-level version on that page.
by wd5gnr
Wed Jan 12, 2005 7:58 pm
Forum: General Discussion
Topic: HELP UV lamp needed
Replies: 5
Views: 1453

Re: HELP UV lamp needed

I'm guessing you could find it at http://www.bulbdirect.com
by wd5gnr
Wed Dec 15, 2004 5:32 pm
Forum: General Discussion
Topic: Need advice! B.SEE or not?
Replies: 16
Views: 3512

Re: Need advice! B.SEE or not?

There are only a few legitimate online BSEE degrees and I don't think there are any that are ABET accredited. There are a few BSEET degrees available. It all depends on what you want to get out of it. If you want a Professional Engineering license, ABET is a must. Also, many graduate schools will fr...
by wd5gnr
Fri Dec 10, 2004 11:53 am
Forum: General Discussion
Topic: Al Williams, Book
Replies: 10
Views: 2013

Re: Al Williams, Book

Glad they fixed it for you. Time was when they pressed these CDs, but I don't know if that's still true or not. A pressed CD won't have the two colors.<p>Let us all know when you sucessfully make your first board!
by wd5gnr
Tue Dec 07, 2004 6:27 am
Forum: General Discussion
Topic: Joke thread?
Replies: 28
Views: 4878

Re: Joke thread?

Ok, I'll play. I grew up near southern Louisiana where there are lots of Cajuns. They are known to like hunting and fishing of all kinds. This is my favorite Cajun story:<p>Tibeadeaux was cleaning his boat. Two of his buddies come by and one of them says, "Oh, Tibeadeaux. We got sum good news and su...
by wd5gnr
Tue Nov 30, 2004 7:42 pm
Forum: General Discussion
Topic: Al Williams, Book
Replies: 10
Views: 2013

Re: Al Williams, Book

Just to weigh in, I don't have much to do with the actual production of the book (that's McGraw Hill's thing). However, I would expect the CD to be pressed since they make quite a few of them at once.<p>I've passed this on to McGraw Hill customer service and I'm sure they will send him a replacement...
by wd5gnr
Sun Nov 14, 2004 6:09 am
Forum: General Discussion
Topic: PCB Layout Software???
Replies: 18
Views: 3617

Re: PCB Layout Software???

If you want an Eagle tutorial, as well as info on how to make your own boards or send Gerbers out to be made, have a look at:
This book in the N&V Store<p>73
by wd5gnr
Fri Oct 29, 2004 9:48 pm
Forum: Computer Programming
Topic: Have VB Create a .csv file
Replies: 2
Views: 1594

Re: Have VB Create a .csv file

A few comments. First, check out this free ActiveX control: http://www.al-williams.com/npdaqax.htm . It is made to work with our Netporter product, but it turns out it is easy to use in many other cases.<p>Once you have your data, it seems like you are going to want to print your data like this:<p>P...
by wd5gnr
Tue Oct 26, 2004 11:53 am
Forum: General Discussion
Topic: Atmel Help
Replies: 1
Views: 859

Re: Atmel Help

I have a tutorial aimed at the ATmega 8 and the GNU C compiler (also see this month's N&V for a data logger around this same set up). Since the compiler masks a great deal of the differences between AVR devices, it should be of some use to you.<p>Have a look at http://www.awce.com/classroom <p>In pa...
by wd5gnr
Sun Oct 17, 2004 12:54 pm
Forum: General Discussion
Topic: cold heat soldering iron
Replies: 9
Views: 1331

Re: cold heat soldering iron

I looked at these awhile back (would be great for antenna work). I have read they "spark" near the work and their site suggests you do not solder "sensitive" components with it. This makes me think it is a resistance welder. That is, it generates current through the metal to be welded and that is wh...
by wd5gnr
Mon Oct 11, 2004 8:46 am
Forum: General Discussion
Topic: LM34 to computer
Replies: 15
Views: 3141

Re: LM34 to computer

If you really need to read an LM34, consider a PC-connected A/D converter. For example:
the GP-3 adds several A/D, some digital I/O, PWM, etc. and programs in VB, Java, C, JavaScript, VBA, etc.<p>If you want to use the joystick port as someone else suggested, consider just using a thermistor.