Re: Can a preamble be transmitted without the use of a PIC controller?

You can't use a 555 etc. as it will not be synchronised to the data 
timing, and will glitch at the transition between preamble and data. 
 One easy way is to simply add some $55 (binary 010101010) bytes to the 
head of the data stream. You will also usually need to add a code at the 
end of the preamble to indicate the end of the preamble and the start of 
the data, otherwise the receiver won't know which bit to start decoding.