how do I turn a commercial radio reciever into a transciever for
instance in a survival situation I wanted to communicate and had a
somesort of handeld fm radio.  What would I need to send out an
emergency signal?  Refrences?

At "http://www.aaroncake.net/circuits/fmtrans.htm" you can see a
simple fm transmitter. From looking it over you can see that: 1. The
broadcast range is not sufficient for an emergency signal. 2. Creating
a transciever would probably not be possible because you would need to
remove parts of the radio to create a transmitter, assuming the radio
contained the parts and they could be effectively held together.

"http://www.geocities.com/bewolf.geo/FMtx.html" is possibly more of
what you are looking for, but again the broadcast strength is probably
not great. You would also need more parts for construction and this
design may not be tested.

Something like a emergency transmitter (like this:
http://www.lifesupportintl.com/EBC-102.htm )is all you would probably
need in a wilderness survival scenario. I would recommend taking
something with you if you're travelling far from civilization, atleast
a signal mirror and atmost a transmitter.

Hi virgilxavier-ga,

  Assuming you do not have a transmitter, it might be possible to use a simple
switch and a microphone(or even the speaker in the radio as a dynamic
microphone) in conjunction with the local oscillator (almost all the commercial
receivers should have atleast a single conversion ckt) of the receiver as a
low power transmitter.  If you are aware of the ckt. diagram of the receiver,
you should be able to hook up the speaker into the local oscillator, or just
interrupt the oscillator carrier to send cw morse code transmissions.  You
also might have to connect the oscillator output to a big wire(acting as an
antenna) in the tranmitter mode(through the same switch) to increase 
trasmission range. You could also calculate the rought local osc frequency
(tuning freq+-Intermediate freq), to make it coincide with a known emergency
frequency to send out your morse code sos signals, to describe your location
and even request a switch over to another clear frequency for the two way
communication later.

Hope this is what you've asked for.

Regards
ldavinci-ga