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Can I use a 555 timer IC to make an amateur radio? Answered

                    I'm thinking about starting to do amateur radio, but I don't want to pay a ton of money for a transceiver.  In theory, couldn't I use a 555 timer with a frequency modulated by a microphone to generate FM, which could then be amplified and transmitted?  Just curious about it.  Also, couldn't one do the same thing in reverse, just finding a way to tune a 555 or something so that it would output audio when tuned to a specific frequency from an antenna?  Just a thought. 


Take a few minutes to look up the "RockMite" series of Morse Code trancievers. US$ 30, one band, one frequency, (crystal control) about one watt. Choice of 80M, 40M, 30M or 20M.

Also look at www.qrpme.com the Sudden Storm reciever and the Tuna Tin Two transmitter in the US$ 30 range.

In Australia the same rule applies " if it is within a 10block region of transmition, then its fine"

Get your license first.

All will be revealed.

oh, and sometimes if you join a radio club you might find someone that will Loan you a radio transmitter till you can afford your own.

or you could buy one 2 meter radio used for as little as $40

or you could do as I did one time... trade stuff for one.
In the mean time QST magazine published by ARRL has had low power transciever projects printed.


I would recommend using an oscillator and stereo transformer and jack if you want to transmit AM. Google "Scitoys radio transmitter"

Remember that 'FM' is a scheme for encoding information (modulation) - you can transmit FM anywhere on the spectrum.  A 555 timer can be used to encode your voice into FM fairly easily (look into using it in astable mode - your microphone will take the place of one of the capacitor / resistor depending on the microphone type). 

it's not well suited for wireless transmission, though.  The max frequency of a 555 is around 500 kHz.  The lowest amateur radio band is 160 meters (1.8MHz).  You could take the output of your 555, but you'll need plenty more circut to move that baseband signal to a carrier. 

Hope it helps!  I got my license a while ago and have had a lot of fun with it - if you're really interested in amateur radio, ARRL is a good place to start. 

If I might suggest that since you're just getting started in amateur radio you try some proven designs before starting to design your own transmitter.  There are lots of ways to generate a signal but without the test equipment and experience you won't know if your signal is legal or not.  There are many way that you might be transmitting signals that are illegal and may even be interfereing with emergency services.

There are lots of less expensive projects you can start with.  Click this link to get a start.

Using a 555 timer to build a radio seems to be very limited from what I've found.

A better link for diy radios is here.

Depending where you are, there are shed-loads of regulations to be aware of.

UK Guide.

In Europe, FM transmitters do not need a licence if their power is 50 nanowatts or lower.

In America, they (apparently) can be more powerful ("FCC Part 15").