Search found 56 matches
- Wed Mar 17, 2010 8:03 am
- Forum: General Discussion
- Topic: Voltage converter
- Replies: 6
- Views: 3865
Re: Voltage converter
The describing equation for the OP's circuit is simply: Vout = 5 - Vin. The Kirchoff's current equation for the inverting node of an inverting amplifier is: I1 = (Vin / Rg) = -I2 = -(Vout / Rf) This assumes a 'virtual ground', or zero volts, at the inverting input, because the non-inverting input is...
- Sun May 25, 2008 1:43 pm
- Forum: Projects & Kits
- Topic: A Simple Superhet by John E. Post, March 2008
- Replies: 3
- Views: 6010
- Sat May 24, 2008 7:59 am
- Forum: Projects & Kits
- Topic: A Simple Superhet by John E. Post, March 2008
- Replies: 3
- Views: 6010
A Simple Superhet by John E. Post, March 2008
I do not understand how to connect the antenna (L1) to the SA602's input amplifier. The problem is that the antenna is depicted as a transformer (see schematic below) when in reality it is an inductor. In other words, the antenna is a two-terminal device, not a four-terminal device. http://users.ade...
- Tue Sep 25, 2007 6:01 am
- Forum: Computer Programming
- Topic: Need help on using AVR CodeVision C compiler
- Replies: 14
- Views: 15675
- Wed Sep 05, 2007 4:50 pm
- Forum: General Discussion
- Topic: Technical Dictionary
- Replies: 9
- Views: 12312
Here is another electronics dictionary
http://www.electronicdefinitions.com/
http://www.electronicdefinitions.com/
- Fri Nov 24, 2006 4:55 am
- Forum: General Discussion
- Topic: Any spare gold soldering tip, please ?
- Replies: 17
- Views: 10412
Antex makes a gold-plated tip. Is this what you are looking for?
http://www.mmnewman.com/shopping/shopex ... 1&catid=20
http://www.mmnewman.com/shopping/shopex ... 1&catid=20
- Wed Nov 08, 2006 4:55 am
- Forum: General Discussion
- Topic: Optoisolator selection
- Replies: 6
- Views: 4395
Now that I have received the recommended optos, I have a question about their use. Here is the internal schematic of the part: http://users.adelphia.net/~andrewconklin/FOD050L.png The data sheet says the following: A separate connection for the bias of the photodiode improves the speed by several or...
- Tue Oct 31, 2006 6:59 pm
- Forum: General Discussion
- Topic: MicroChip PIC30F Assembler
- Replies: 10
- Views: 7527
- Tue Oct 31, 2006 5:55 am
- Forum: General Discussion
- Topic: MicroChip PIC30F Assembler
- Replies: 10
- Views: 7527
Here is an excerpt from a 30F document: Unlike the MPASM™ assembler (for use with PICmicro® MCU’s), MPLAB ASM30 does not generate error files, hex files, or symbol and debug files. MPLAB ASM30 is capable of creating a listing file and a relocatable object file (that may or may not contain debug...
- Tue Oct 31, 2006 5:25 am
- Forum: General Discussion
- Topic: MicroChip PIC30F Assembler
- Replies: 10
- Views: 7527
There are two gross over-simplifications in markp's desires. The first is the notion that it is possible to create an executable without a linker. The second is the underestimation of how much more complex the programming specification is for the newer, 16-bit PICs, such as the 30F series. The 16-bi...
- Thu Oct 26, 2006 6:51 pm
- Forum: General Discussion
- Topic: Optoisolator selection
- Replies: 6
- Views: 4395
Oh, the hardware portion of my programmer is a piece of crap - I would give its schematic away for a nickel. The part that took time was the PC software. It's not great, either. I bit-bang the parallel port as fast as possible using a high speed clock available on the PC. I hope these new optos impr...
- Thu Oct 26, 2006 12:14 pm
- Forum: General Discussion
- Topic: Optoisolator selection
- Replies: 6
- Views: 4395
Thanks Philba, I put some on order. I learned a hard lesson with this - Mouser carries much more product than they put into their catalog. I could have saved a few dollars on the 33F's by ordering from them rather than MicrochipDirect because the Mouser catalog did not list the 33F series when in fa...
- Thu Oct 26, 2006 7:39 am
- Forum: General Discussion
- Topic: Optoisolator selection
- Replies: 6
- Views: 4395
Optoisolator selection
I am a hobbyist embarking on the conversion from the dsPIC30F to the dsPIC33F series, and since the 33F is 3.3V device, I plan to build a new programmer for it. My current home-brewed programmer uses 4N25 optos to isolate the PC's parallel port signals from the target. It is painfully slow. I had to...
- Fri Sep 22, 2006 3:52 pm
- Forum: General Discussion
- Topic: Power Supply 'Hot Swapping'
- Replies: 5
- Views: 3442
You cannot prevent all accidents from happening. It will require some prudence on the part of the operator. Install an E-stop and LED indicator in series with the DC voltages. We had a similar circumstance in my last job wherein we hot-plugged Molex connectors to our drives and sometimes we would bl...
- Fri Sep 22, 2006 3:20 pm
- Forum: Computer Programming
- Topic: Terribly new question.
- Replies: 9
- Views: 8309