Search found 93 matches
- Tue Apr 24, 2007 7:37 am
- Forum: General Discussion
- Topic: Fooseball goal sensor
- Replies: 9
- Views: 4396
For the cub scouts pinewood derby track, I used a laser from the junk store, $2 each and I mounted it vertical above the track. In the track I had a visible light sensor with the laser pointed at it. That cost me <$3. I fed the light sensors into a micro and we could determine the winner and flash a...
- Tue Apr 24, 2007 7:27 am
- Forum: General Discussion
- Topic: Op Amp Circuit Help
- Replies: 6
- Views: 3448
- Tue Apr 03, 2007 11:39 am
- Forum: General Discussion
- Topic: Op Amp Circuit Help
- Replies: 6
- Views: 3448
Op Amp Circuit Help
I just do not get along with op-amps. I like them, they just don't like me. :) I need to take a 2.8vrms AC sine wave (7Khz), reduce the voltage to 500mv and invert the 500mv signal so I have two signals at same voltage, 180° out of phase. I know the good old 741 will do it. Can anyone point to an e...
- Thu Feb 22, 2007 11:42 am
- Forum: General Discussion
- Topic: Accurate Frequency generation
- Replies: 6
- Views: 3414
- Wed Feb 21, 2007 2:17 pm
- Forum: General Discussion
- Topic: Accurate Frequency generation
- Replies: 6
- Views: 3414
Accurate Frequency generation
We use a crystal in one of our pc boards that the user can replace with different values to get different carrier frequencies. The crystals on both ends of the communication devices have to match. I would like to build in a programmable frequency generator, but it needs to be accurate like a crystal...
- Thu Jan 25, 2007 7:27 am
- Forum: General Discussion
- Topic: Need to control 16 digital outputs based on 16 analog inputs
- Replies: 10
- Views: 6201
- Thu Jan 25, 2007 7:13 am
- Forum: General Discussion
- Topic: Need to control 16 digital outputs based on 16 analog inputs
- Replies: 10
- Views: 6201
Have you looked at a PLC yet? Go to www.automationdirect.com They have the best prices. Select a CPU type and add as many analog modules as needed. You could have relay or solid state outputs. The CPU will allow PID loops which is the type of control usually needed for temperature. A DL06 would prob...
- Thu Jan 04, 2007 11:35 am
- Forum: General Discussion
- Topic: Test for Nickel
- Replies: 5
- Views: 3899
- Wed Jan 03, 2007 6:16 am
- Forum: General Discussion
- Topic: Test for Nickel
- Replies: 5
- Views: 3899
Test for Nickel
My freind thinks he found a meteorite on his farm. It has to have iron and nickel to verify. We can make a magnet on a string move so we are sure it has iron. What can we do to test for nickel? Thanks.
- Wed Nov 01, 2006 1:20 pm
- Forum: Up For Grabs
- Topic: Smart Block
- Replies: 1
- Views: 3430
Smart Block
I have a number of SmartBlock CPU boards. They are circa 1991. Never used. They have a Zilog Z80 micro, eprom, ram and RTC all on one board. Are these worth anything to anyone???
- Mon Oct 30, 2006 2:25 pm
- Forum: General Discussion
- Topic: Daylight Saving
- Replies: 19
- Views: 9080
Daylight Saving
http://www.infoplease.com/spot/daylight1.html So.... How many products are going to malfunction next year because they were programmed with automatic daylight saving adjustments? Next year daylight savings changes by about a month. Congress approved it 2 years ago. My VCR was made 6 years ago. It au...
- Mon Oct 02, 2006 3:00 pm
- Forum: General Discussion
- Topic: EL Backlight
- Replies: 0
- Views: 1551
EL Backlight
I ripped my ViewSonic lcd monitor apart. The backlight is intermittent. It will turn on sometimes, just not always and definately never twice in a row. It uses a TI TL1451A, buck boost chip. I see 12V on the chip and when working, I can measure the pulses that the chip creates. When the backlight is...
- Wed Aug 16, 2006 8:09 am
- Forum: General Discussion
- Topic: Overlay design software
- Replies: 2
- Views: 2083
- Tue Aug 15, 2006 2:27 pm
- Forum: General Discussion
- Topic: Overlay design software
- Replies: 2
- Views: 2083
Overlay design software
I remember a year or two back that some company came up with some free software you download and run that allowed you to design a metal graphic overlay for a control box. After designing the overlay, you could order the overlays from them. I can't seem to find the website. Anyone remember that?
- Mon Feb 27, 2006 11:33 am
- Forum: General Discussion
- Topic: lowest cost mcu and how to mass produce
- Replies: 13
- Views: 5346
Re: lowest cost mcu and how to mass produce
Look at www.holtek.com and www.holmate.com You develop on an HT-ICE and they have OTP or they will do a mask where your program is factory-programmed. There is an up-front charge for this. This can get your huge quantities down to .50 a chip or less.