Search results

  1. keile

    remote control using radio freq

    Greetings! I wanted to take this time to thank everyone for sharing their time and knowledge to make this project possible. At last, we passed our design project. The only downside is that we had used infrared instead of radio frequency to give us more time to focus on the encoding and decoding...
  2. keile

    free radio frequency

    thanks a million audioguru!! just what i needed :)
  3. keile

    free radio frequency

    what is the radio frequency that is available for use with any electronic devices without the need for a license? after researching this is what i found: 40 Mhz - garage door, alarm system 40-50 Mhz - standard cordless phones 49 Mhz - baby monitors 27 & 49 Mhz - basic consumers items i'm...
  4. keile

    remote control using radio freq

    hello! thanks Chester for some thought :) yeah.. maybe there's some step-up ic inside .. coz the device also light a red LED to indicate if there's a signal (i know LED doesn't work on 1.5v). it's around 10 days before our defense and i hope we can get the circuits fully working as soonest...
  5. keile

    remote control using radio freq

    i opened my father's wireless microphone receiver and it contained an TDA70** ic (sorry i forgot what number)... and it only runs on AAA size 1.5V battery.
  6. keile

    need help in fm transmitter

    to audioguru: uhh sorry.. actually i just want this thread to focus on transmitter thing.. and to ask all about its variations.. i have researched lots of transmitters already and always wondered why it differed in many ways.. wow.. i didn't know that the capacitor has a value of 5 to 40pF...
  7. keile

    remote control using radio freq

    yeah.. hopefully we can make a fully working prototype by next week.. I checked TDA7000 and TDA7088 IC's and looks like they're a complete fm receiver with no amp.. and I assume MC3361 and MC3362 is the amp right? I wanted to run my receiver with 1.5V battery to reduce weight and I think...
  8. keile

    need help in fm transmitter

    thanks a lot for explanation audioguru! actually for the mic i wanted to replace it with a 555 timer to generate tone so an amp might not be needed? also, the trimmer capacitor has no value.. i don't know.. maybe it is just optional.. btw, i got the schematic at this site...
  9. keile

    need help in fm transmitter

    hello! i got a very simple fm transmitter yet very stable, low power and have reasonable range (the author claims) i'm having a problem to get it working.. :( I don't know if the 28pF capacitor which is connected to the collector has something to do with the parallel resonant circuit. Also...
  10. keile

    for an idea

    try 555 timer configured as monostable.. components resistors and capacitors determine the time..
  11. keile

    Radio-Amateur

    try this simple FM transmitter that could transmit at a max distance of 50m with only 3v supply http://tacashi.tripod.com/elctrncs/smplfmtr/smplfmtr.htm
  12. keile

    remote control using radio freq

    hello! so far this is the flow of my circuit: 555 timer(information,encoder) -> fm transmitter(carrier, modulator) ~~~ ~~~ fm receiver(demodulator) -> PLL (decoder) -> output i'm now in the process of testing transmitters and receivers.. i' ve come across this very nice fm...
  13. keile

    remote control using radio freq

    wow! trigger I can't believe it!! You actually found it! :) oh thanks a lot!! it's so similar that it only needs few customization or maybe not? hehe.. thanks again!!
  14. keile

    remote control using radio freq

    thanks.. i'll check it :)
  15. keile

    Simple Transmitter/Reciever

    wow that's so cool!! how about drop a handful of black colored rounded object? heheh.. seems like a war zone :P
  16. keile

    remote control using radio freq

    thanks trigger! :) i have researched on the tone detector IC LM567 and found it.. uhh.. confusing ??? well, i have decided to take a look at my electronics book if I could find anything that would help my project. Phased-Locked Loop interest me. After reading all the explanation in the book...
  17. keile

    remote control using radio freq

    hello I'm back! :) btw, before I continue on.. I would like to give a lotta of thanks for trigger and MP for helping me on this project.. thanks a lot!! Something strikes me while listening to my instructor bout 555 timer. And this what I think how my circuit should be (below) and now i...
  18. keile

    Simple Transmitter/Reciever

    wow that was quite similar to my project.. anyway I think this is similar to the details you have described: http://www.electronics-lab.com/projects/motor_light/037/index.html
  19. keile

    remote control using radio freq

    oh so a higher frequency has lots of difficulty in terms of building a transmitter... do you have any idea how can i avoid interference if I use a lower frequency like 433Mhz? ???
  20. keile

    remote control using radio freq

    to MP wow! that's one hell of an amazing device!! honestly, if I look and examine its every detail, its perfect for my project. With its security and features.. wow.. but the 433Mhz chip cost around $54 uhh.. but a whola thanks!! to trigger this is what I have tentatively decided: minimum of...
Top