help with fan controller X10

Hi everyone need some help in making a fan controller with X10 protocol. I have the AN of microchips web as a beggining but i was wondering if there`s more explained info around. It has to work with 240 v ( 50 Hz) since im in Argentina. This is not intended for money, I need to do this for last year of college. I also have some doubts on the AN that i will post in few days. Im still learning assembler and have to do the source code of the pic(16F84), any help on that would be great. My idea is to use a triac to control (pwm) the fan, not sure yet. Well, thanks for your time in reading this and Ill write back soon with my concept doubts of some things in the AN 236 that i suppose many understand. See ya,
Iova.

PD: the AN 236 is downloadable from www.microchip.com

When I reffer to more info it means X10 code examples , detailed explanation of circuit parts used in fan controlling , calculations of everything (for 240 v) etc....every help is welcome!!!!!!!!

My doubts based on AN 236 (microchip) are as follows :
1_ What are the C and R (bleeding resistor) at the front end (where we detect the 120 khz) for exactly? Does the high reactive imp of the C down the value of the 220 v or how does it go down? The R is only to download the C in case of needing? After the R/C the value of 220 v is acceptable?

2_ After the parallel RC we have a high pass filter: I understand that i high pass filter is done with a C and a R where the Vout is through the R (thats why its put to ground......what a dont understand is why before the C there is an R of 10k and after the 33k R to ground there is another C (150pF) with same value as the one before..........(if you see the circuit from AN236 youll get it)?

3_ How does the inverter in mode amplifier (with R in parallel ) work?dont understand how it amplifis...i know it does cause of datasheet ..but theoretical how does it happen........and in the amplification stage untuned
what are the C (10pF) for???

4_ Can someone explain me well how that envelope detector works!!!!!!how does the signal (120khz) pass through the diode?????why is it turned around???I imagine that this last part is to have -5v always to the pic and +5 when the carrier 120khz is present...but how does this happen in detail?????
5-The zero cross detector in 16F84 is made with just a R connected to RB0.....can this really be connected directly to 220 v?????? How do I make with that a cross detector??do i have to program it??does the pic have a cross detector in RBO ?really dont get it......



Well....those are mostly my doubts hope someone with lotta pacience can help me jejejeje......my idea is to control a triac by connecting its gate to an output of the pic (R between both to limit current) and by software let it work more or less acording to which speed i need de fan to go...is this correct?????
Any websites, calculations for 220v (50 hz), notes, circuits, assembler software, books , etc will be very well received ..thanks a lot ...great forum..congratulations...see ya soon,
Iova.