Design

Tek TDS420 help?
This scope has the famous "FAIL ++ Acq" error which points to the infamous failed (and leaking) SMD caps on the acquisition PCB. I'm moving on to troubleshoot another (unrelated, I think -- and hope) issue. During the 25 second "on" period, relays click on & off, the monitor goes through it's boot display (a... 2 Feb 2010 22:23

Favorite BJT transistors, sot-23 and TO-92 equivalents - I
Working on a table for our book, soliciting your opinions, info and advice. For example, try these: '3904 ans '3906 = jellybean? MPS5179, PN5179, MMBT5179 -- what's PNP equivalent? BC547 NPN, sot-23 equiv = BC847, right? BC557 PNP, sot-23 = BC857 ? can I just show the C-grade high-beta variant? ... 17 Feb 2010 00:22

Basic Tools for Surface Mount.
I'm needing to get some basic tools for surface mount stuff. Already have a heat gun and soldering station plus basic electronic instruments, meters & scope. Need magnifier, would the head band type or a clamp on arm lamp/magnifier be best? Or both? I guess tweezers? Do you use some sort of paste to hold... 11 Feb 2010 11:41

Atmel PLD programming help
Hi folks, I'm in need of some info from someone who knows a lot more about this stuff than me! In a nutshell, I've never used programmable logic before, but I really want to get into it. I think it would make my life so much easier, because standard glue logic means so many wires, board space, and potential pro... 2 Feb 2010 16:28

DIY studio strobe
Hello, I would like to build my own studio strobe, based on the following design [I am well aware about the risks of high voltage/current!]: http://www.diyphotography.net/diy-home-made-power-pack-flashes#great-idea The only thing I would like to further implement is a control on the flash duration/power. T... 4 Feb 2010 17:58

inverting dc-dc converter circuit
This afternoon we were talking with Phil Hobbs about an electro-optical thingie we're doing. The prime power is a +15 volt wall wart, and we need -30 internally to power some photodiodes and opamps and stuff, 30 mA maybe. Our design currently has a cute homebrew single-inductor flyback converter, which circuit ... 6 Feb 2010 12:59

Very low frequency 100 microvolt/sec triangle ramp with adjustable limits and slope
On Thu, 28 Jan 2010 16:01:13 -0800 (PST), Bill Sloman <bill.sloman(a)ieee.org> wrote: A 24-bit sigma-delta D/A converter from Burr-Brown (now part of TI) turned out to be pretty attractive; for the slow rates I was planning looks like 20 bits is the best they do now (DAC1220) ... 15 Feb 2010 14:20

Something weird just happened...
The internet connection went down for 1 second or so. Then it didn't work... I walk to the cable modem and blow off the dust... and everything works again ! So I guess it was just some dust on it ? Hmmm... Bye, Skybuck. ... 2 Feb 2010 16:23

Is this an ink flow sensor? (Ink Jet printer)
I'm trying to troubleshoot an error with an HP ink jet printer (Photosmart 3210) that says "Ink System Failure". All other components seem functional. In the printer there is a small PCB with a few soldered components that appear to sense ink flow or pressure. It is in series with the pump output. <http://i... 4 Feb 2010 17:58

Soundcard with 3rd octave eq
Does anyone know of a soundcard with a third octave equalizer? -- Dirk http://www.transcendence.me.uk/ - Transcendence UK http://www.theconsensus.org/ - A UK political party http://www.blogtalkradio.com/onetribe - Occult Talk Show ... 2 Feb 2010 16:22