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Charlie Foxtrot Mike:
Hello everyone! I'm just starting here so after saying hi I'd like to ask about this. I want to build/buy a Transmitter for broadcasting, and looking for it I've found many circuits I could try (guerrilla, spitfire, LULU, etc). Wich one could be right to start? I live in the south of the south of South America, only woods here so I could transmit without stress. The other thing is, I could have one or two cb radios that nobody uses here... Is it possible to modify them for broadcasting? I thank you in advance for any tip or help.  Salud!
CFM

ff:
Hi CFM!

The way I see it - your building experience should determine your choice about what design to build.  The way I would rank these:

1) Little or no experience building RF projects - Radio Anarchy's Guerilla would be a good starter rig.

http://www.angelfire.com/de/RadioAnarchy/

2) You've worked with small transmitters before but not a lot - the Lulu would do you well:

http://hfunderground.com/blog/?p=72

Or Dave Martin's Corsair:

http://freeradiotx.blogspot.co.uk/2009/06/corsair-transmitter-by-dave-martin.html

3) Dave Martin's Commando is a great rig but you should have some real experience before attempting:

http://freeradiotx.blogspot.co.uk/2009/06/command-transmitter-by-dave-martin.html

There are even better designs out there such as the Dutch Quad, but you really need building experience to get them working.

CB radios are fine to pirate with as long as you don't try to move the frequency too far from 10-11 meters.  The old units that use crystal mixers to synthesize the channels are pretty easy to trick to other areas.  But IMHO if you need to ask the question then you probably won't be successful at this.  It takes some knowledge to convert these.  BTW- Pirating up in that range can be a lot of fun - when the band is right, 5 watts will really kick a$$ - but you lack the large listening audience that exists on 43 and 48 meters.  I hope this helps...

Charlie Foxtrot Mike:
Hey ff, thanks for the complete answer. I'm completely new to RF electronics, so I guess The Guerrilla would be OK. Only that I guess I have to buy everything from the states or UK, cuz here there's no complete electronic supply store. I'm still thinking about the transformers and wire winding... Well I guess I'll start searching now :).
About the cb radio, as it is, it won't broadcast unless it is modified, right? I mean, thinking about transmit for an hour or so with no pause.  Thx again. Now is time to read about electronics.  :)
CFM

ff:

--- Quote from: Charlie Foxtrot Mike on June 07, 2015, 0328 UTC ---About the cb radio, as it is, it won't broadcast unless it is modified, right? I mean, thinking about transmit for an hour or so with no pause.
CFM

--- End quote ---

You should make sure the final transistor has proper heatsinking.  On older units, often you can get away with homebrewing some extra heatsinking fins that extend up above the transistor, then use a fan.  Of course you'll need to put the chassis in a larger case that will fit everything.  My best advice would be to NOT pirate in the 10 meter ham band or in the CB band.  Lots of angry users will give you the wrong kind of attention.  If you want to use an old CB, make sure you can trick it to operate lower - perhaps in the 11 meter shortwave band or just above.  I have a homebrewed 5 watter that I use in the 25800-26000 area occasionally.  Play it safe, my friend...

Charlie Foxtrot Mike:
Of course my friend. I want to broadcast cuz I have things to tell and music to show but not to annoy people  ;). I am a hater myself when people doesn't respect others on Amateur Radio Bands. I was thinking about modify the cb radio, knowing that is possible to use it on 40 meters, maybe is it possible to move a lil further to the 41 meters? Right now I'm searching for the pieces in Aliexpress :)  there's everything in there. I'd appreciate if you or anyone here could later, when I'm ready to buy, take a look at the list to see if I'm not doing a mistake. Guerrilla Project has begun. Thanks again. Gonna keep you updated (of course the action gonna start in one month or maybe more, depending on how long the shipping takes).
CFM

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