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Everything posted by harsh

  1. i just had a heck of a time retriving/changing my password maybe it should be fixed ? others probably would have given up the problem was the link in the email sent to my address was not complete ie the underlined part only covered part of the whole link , thus when clicked on it sent me back to the same page that i requested the change from.
  2. J-type thermocouple Definition: A thermocouple best suited for measurements in the 0 to 480 degree © range. The positive conductor is made of iron, and the negative conductor is made of constantan. May i put my two cents in here ? mrtrhs, how about a radioshack thermistor? i realize that you may not have a "shack" around the corner ,but the thermistor ,in my opinion , is the way to go. You could set up a voltage divider using 5V as a supply voltage. Just a suggestion.. ;D Oh ... What temperature range are u thinking of measuring?
  3. I dunno Ante thats what it says.. ??? ??? http://www.electronics-lab.com/projects/rf/001/index.html
  4. From your origional posted picture.. yeah i'd say they are loosly wound.
  5. i believe this should read 75 "ohms' not watts.. so u should just take the center conductor out of a coax cable, and wrap it around a 7mm diameter rod and u are good to go. i am not sure if u can substitute a 2n2222 for the 2n2219 transistor. i am sure somone else will know that.
  6. I hear ya . Nothing wrong with that .!!. ;)
  7. have you ever heard of a USB drive ? pretty neat little packages.. http://www.usbmall.com/products/viewitem.asp?idProduct=203&linkid=2
  8. quantum , what didnt work the laser? or trying to turn off the street light.
  9. 1980 vintage catalytic converters had platinum in them No ?..
  10. has anyone seen this site while we are on the subject of alternative fuels. www.geobacter.org this guy uses microbes to generate electricity
  11. all parts can be gotten at radio shack.. PART LIST 1) Thermistor 1) LM339 Quad Comparitor 1) IFR 510 Mosfet transistor N channel 1) 10K varible resistor 1) 10K resistor 2)330K resistors 1)2.2K resistor
  12. i decided to try a comaprator .. the LM339 quad comparator.. and it worked *yay*.. and is working as we speek.
  13. http://www.amasci.com/freenrg/bedini.txt :)
  14. this is a useful graphing program i use http://nces.ed.gov/nceskids/graphing/line.asp
  15. hi nestorages, this is the deal, u cant use a transformer with Direct Current ( DC )from a battery. here is why a transformer only works with Alternating Current ( AC ). if you were to touch the battery to the windings of the transformer and removed it ,u might notice a little spark, that spark is caused by the collapsing magnetic field. same principle as the automotive ignition system. hope this helps..
  16. typing a ? produces this list of debug commands.
  17. harsh

    TTL 74AS IC

    do you need AS series? i am pretty sure the ALS is the same but lower power..
  18. Warning !! USING DEBUG CAN SERIOUSLY MESS UP YOUR SYSTEM AND THIS MESSAGE BOARD IS NOT RESPONSIBLE FOR ANY DAMAGE YOU MAY CAUSE !! When using debug you may have to reboot so it is best to try it with no other programs running.. with that said debug can also be a lot of fun.. for example it gives u the ability to " poke " in small assembly programs and run them.. and watch the registers change..BUT be warned.. see above. i didnt think it had debug. but i just tried it and it worked.. start -->all programs --> accessories --> command prompt.. at the prompt type --> debug and hit the enter key when debug is working it will show a line with a blinking underscore--> --_ at this point u can see the internal registers by typing r then enter.. there are many other commands that debug has if anyone is interrested i could post them also. to Exit debug type q enter. to Exit command prompt type exit enter. Warning !! USING DEBUG CAN SERIOUSLY MESS UP YOUR SYSTEM AND THIS MESSAGE BOARD IS NOT RESPONSIBLE FOR ANY DAMAGE YOU MAY CAUSE !!
  19. harsh

    TTL 74AS IC

    hmmm sorry, i thought they did , but u r right, they dont..
  20. harsh

    TTL 74AS IC

    www.jameco.com they are pretty good and will deliver in a few days.
  21. i found it.. a fan controller huh .. nice... thanks
  22. thats exactly what i was looking for ;D i cant read whats written under the circuit :( the mic-502 is an op amp?
  23. this is sort of being discussed here http://www.electronics-lab.com/forum/index.php?board=21;action=display;threadid=192
  24. i need a circuit to turn a relay on and off. the relay controls 12 volt fans. the control condition is heat, which comes from my refrigerator, and the fans vent the heat away from the cooling fins. so when frige comes on i would like to have the fans come on shortly thereafter. and when the frige goes off i would like to have the fans go off. i could even do it without a processor using an a/d converter, but i dont even want to use an a/d converter, seems like overkill. the circuit should be simple , maybe using an op-amp ,maybe. options: thermistor with changing resistance.. but how do i turn a changing resistence into what i need ? driveing the relay isnt a problem assuming i have a signal to drive it with. so i have a changing resistance ,and i am working with 12 volts i think the relay is 12 volts also Thank you. william
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