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I need help

  1. Apr 21, 2012 #1


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    I'm new in this site

    I need help here please

    I need a circuit that works as :

    1- transmitter uses radio waves or any type of waves
    2- sends waves for long way more than 3 km
    3- consist of simple component than can be found in old electronic instruments such as old TV or radio

    please help me

  2. jcsd
  3. Apr 21, 2012 #2


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    You may mean vacuum tubes. Transmitters can be built using mainly parts from old radios, but I wouldn't suggest you try this without a suitable licence.

    Transmitting is tightly controlled in most countries and penalties may be severe.

    You could check if your local library or Amazon has a copy of the ARRL Handbook for Radio Amateurs. This will give you a start to learn about radio transmitters.
  4. Apr 21, 2012 #3


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    please I'm not engineer but rather have a problem to be solved

    I can't read and study books , I need something ready to be done

    please help and don't care for the law in my area

  5. Apr 21, 2012 #4


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    Homework Helper

    To quote from the Forum Guidelines https://www.physicsforums.com/showthread.php?t=414380 (which you should have read before you posted anything):
  6. Apr 21, 2012 #5
    yk6jkro, you should get a kit of some kind.
    www.ramseyelectrics.com [Broken] has some kits that may meet your requirements. (I've never built a ramsey kit, but they have a good catalog)
    Don't do anything to violate the law, the law have ways of tracking down illegal transmitters.
    Last edited by a moderator: May 5, 2017
  7. Apr 21, 2012 #6
    If you can't read schematic and not wanting to learn, the best way is to butter up friend of yours that know electronics to even help you look for some kits or what not. It is going to be hard to instruct you "hook a wire from point A to point B........" have your friend ask the question here and tell people what do you really need.

    TV and radio are all receivers, I don't think you can pull out a transmitter out directly as there is no transmitter circuit. You have to monkey with the component to do that. If you have a walky talky, at least you have a transmitter circuit in it. AND when you transmit, you need a receiver to listen. You cannot just design a transmitter, they have to go in pair. Start with a walky talky, you have a transmitter and a receiver that talk to each other. Maybe look for a walky talky kit and modify it.
    Last edited: Apr 21, 2012
  8. Apr 21, 2012 #7


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    Thanks 4 your attempts to help:

    although I don't have the ability to learn electronics but I can take the schematic to some of my friends to build it up for me

    I need your special ways , special Ideas

    Don't restrict yourselves to what exactly I've said , but I want components that can be found easily in - poor country- like mine !!
  9. Apr 21, 2012 #8


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    I found such things on net :


    they say it is for 1000m

    what you say
  10. Apr 21, 2012 #9
    As I said, you have to work on this in pair, transmitter and receiver. It is very specific, the receiver has to tune to the transmitter for it to work. Or else we Chinese has a saying......Chicken talking to a Duck!!!!................No body understand!!!!:rofl::surprised

    Go on the web and search for a pair. As I said, a walky talky kit. I am sure you can find a walky talky schematic on the web.
  11. Apr 21, 2012 #10


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    That transmitter would work although some bits seem peculiar. It is for the FM radio band which is about 90 MHz to 108 MHz and you could listen to it on a commercial FM radio. You may already have one of these, although it would need a good antenna to work over any longer distances.

    There are lots of such transmitters on the Net and all of them are probably illegal in most countries.

    I checked about that book I suggested. Amazon have them for about $7.50, but postage could get expensive if you are not in the US. It is quite a heavy book.
    That was for one that was about 3 years old, which would still be fine for your purposes. Up to 20 years old would still be OK.
  12. Apr 21, 2012 #11


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    but still I want something ready and simple and effective and easy to build up and of your owns !!!!!!!!!!!!!!!!!
  13. Apr 21, 2012 #12


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    There are certain necessary building blocks for a transmitter and they all have necessary functions, so they have some unavoidable complexity.

    While you can easily find these by using Google, we operate under a set of rules. Many people read the replies you get and we don't want to propagate information about illegal transmitters.

    It is not that we don't want you to have a transmitter, but we need to know that you know how to make it safe and legal so that it won't interfere with other services and it won't get you into trouble with the authorities in your country.

    For example, that transmitter you showed above could probably be tuned to 120 MHz and this is an international aircraft band. Imagine the trouble you could get into if you transmitted there.

    Amateur Radio exists in most countries and many people find this kind of hands-on experience is the best way for them to learn. There are entry-level licence grades which get you transmitting and building equipment legally.
    If you have a friend 3 km away, why don't you both enrol in a beginner's course in radio?
  14. Apr 22, 2012 #13


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    Thank you for both :
    - replying to my topic
    - advising me for the law

    and Thanks because I think you have what I'm searching for but you can't give it to me for legally demands !

    make sure that my project won't upset the authority in my country because it is busy in killing the people in the protests

    I need these simple technology because it can help some people to survive !!!

    please if you have an Idea for me contact me on the private

    :biggrin:SYRIA IS MY COUNTRY:biggrin:
  15. Apr 22, 2012 #14
    Oh my God. This is getting important and serious. I am not particularly familiar with radio to give any more further suggestion, this is too important to just give suggestion and opinions. Someone with practical knowledge on radio communication should really help out here to get something going. It is getting really desperate over in Syria, people are getting slaughtered everyday. This is no joke and this is not homework. Anyone that can supply practical easy circuit suggestion should help.

    There must be schematic of two way radio etc. on the web that is easier to build.
  16. Apr 22, 2012 #15


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    I'm really very thankful to you
  17. Apr 22, 2012 #16


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    http://a2.sphotos.ak.fbcdn.net/hphotos-ak-prn1/553036_251206364976310_1518334447_n.jpg [Broken]

    http://a6.sphotos.ak.fbcdn.net/hphotos-ak-ash3/538231_251206564976290_100002608451622_486823_1803789018_n.jpg [Broken]

    http://a7.sphotos.ak.fbcdn.net/hphotos-ak-ash3/556454_251206781642935_100002608451622_486824_883687996_n.jpg [Broken]

    http://a1.sphotos.ak.fbcdn.net/hphotos-ak-prn1/522064_251209281642685_100002608451622_486844_2125363273_n.jpg [Broken]

    http://a6.sphotos.ak.fbcdn.net/hphotos-ak-ash4/292545_251208074976139_100002608451622_486837_1212164373_n.jpg [Broken]

    when the army entered this village in Idleb

    all the people escaped

    the army had the names of the people who goes in the protests
    and this is a sample of their houses

    about 300 houses were even burnt or destroyed

    the idea is :

    when the army enter an area , they cut every thing that can be cut such as electricity , communication , water

    I want to solve some of these problems !!! but I'm not engineer but rather have friends but they are still students with simple information
    Last edited by a moderator: May 5, 2017
  18. Apr 22, 2012 #17
    What old equipment do you have available? List active components, such as transistor labels (those would be the green three-terminal elements on your schematic in post #8. The notation 2N3904 is the label of the transistor). There are several types of transistors used today (bipolar, FET). Other types of active components would be electronic tubes (usually look like electric bulbs), tunnel diodes, Gunn diodes, etc.

    One needs to know what you have available because each part has a different mode of operation and all the passive elements (resistors, capacitors), as well as the power supply is built around them.

    What kind of communication do you want to establish? Do you want to talk over the radio? Send Morse Code? Make a remote controlled relay?
  19. Apr 22, 2012 #18


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    thank you very much

    all of them
    especially the last one

    when my friends tell me that they didn't find some of the components , I will put its label here to ask you about something else
  20. Apr 22, 2012 #19


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    I think we should stay out of this one:

    Make a remote controlled relay?

    all of them
    especially the last one

    Why would you think that someone would like to be able to make something happen by remote control at such a distance in these circumstances?
  21. Apr 23, 2012 #20


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    Thank you

    I understand your fears that I would misuse this technology or use it in the Evil
    But I still hopeful that you would understand that we are in a primary life and we are searching for alternatives ;
    we are striving for our freedom . our right to talk , think , discuss and understand ,
    and while the Regime buy with our money high technology to spy with it on us , and to restrict with it our striving , we don't have any of these technology that would help us ;
    we need a way to communicate when they cut the communication ,
    we need a way to turn on a cassette from long way that describe to the soldiers what really happens !!
    and so on .....

    if you like to help me , I would take what ever you would give me , and if not , please let me search for someone can help !
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