Andbor Posted March 23, 2005 Author Report Share Posted March 23, 2005 Hi audiogurunow I tried testing it and I doubled the turns on L1 and L2. ( L1 was ,3 now it is 6, and L2 was 7, now it is 14) Still nothing happened but a strange thing happened: whenever i power up my cirucit, on the fm radio a sort of hissing/crackling noise sound is heard. What can it be? Also, below I am including a copy of what the author had replyed to me when I first asked him if it woked on a breadboard. I tried asking him about how the circuit seperates Am stations, but he didn't reply any more.Thanks_____________________________________________________________hai Quote Link to comment Share on other sites More sharing options...
audioguru Posted March 23, 2005 Report Share Posted March 23, 2005 Hi Andbor,The FM radio makes a noise so maybe the project's tuning is close. Try tuning the project's trimmer cap slowly with a non-metallic tool, with the FM radio at each end of the dial. Quote Link to comment Share on other sites More sharing options...
Andbor Posted March 23, 2005 Author Report Share Posted March 23, 2005 Hi Audio guruOh with a non metallic tool? so maybe that was the problem because i was tuning it with a little screwdriver. What can i use that is non metallic because none can come to my mind?Thanks Quote Link to comment Share on other sites More sharing options...
audioguru Posted March 23, 2005 Report Share Posted March 23, 2005 Yeah, your screwdriver adds 10pF to 20pF to the whole circuit. File a piece of hard plastic into the shape of a screwdriver shaft and glue it into the end of an empty plastic pen.I use a plastic tool for trimmers that has a plastic cup at the end that fits over the trimmer's screw. The cup has melted into it a tiny piece of metal that fits into the groove of the trimmer's screw. It works great for multi-turn trimpots too because it doesn't slip off. Quote Link to comment Share on other sites More sharing options...
Andbor Posted March 28, 2005 Author Report Share Posted March 28, 2005 Hi AudioguruFinally some good news ;D ...The circuit actually worked! We tried seeing it's output with an osciloscope and an FM like wave was there. It was a little difficult tuning it, but finally it worked. However, as you said, too many stations are in 1 fm station and sometimes if you wave yourhand on top of the circuit, the station changes! I think that the circuit name would better be suited to " All waves to Fm convertor" , cause it picks both AM and FM. I would like to thank you very much for your help because it was very usefull! Thanks very much andborP.S: It even picked up a tv station! Quote Link to comment Share on other sites More sharing options...
audioguru Posted March 28, 2005 Report Share Posted March 28, 2005 Hi Andbor,It's great that you got it to work.I was glad to help you and thanks for proving my theory.Sure it will pickup a TV station and if you're near an airport it will pickup the planes and air traffic control. ;D Quote Link to comment Share on other sites More sharing options...
Andbor Posted April 12, 2005 Author Report Share Posted April 12, 2005 For those who would like to try it, I am providing the PCB layout Quote Link to comment Share on other sites More sharing options...
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