fm transmitter


Joined May 16, 2005
What kind of output power do you require. And what frequency range(s) are you looking for? (And are you familiar with government regulations concerning transmitters?)


Joined Apr 20, 2004

With copyright law being so biased in favor of the holders, are you sure you want to take the risk of having the FBI kicking in your door?


Joined Jan 10, 2006
Google these chips.....
and the

They are both PLL controlled Low Power FM transmitters with stereo multiplexing. Stable LPFM on designated frequencies is legal in many countries, but you should probably check your local laws before you start.

There are also a number of kitsets out there as well.... many using the same series of ROHM I/C's... or the earlier inferior Non PLL version (BA1404)

A BH1416 is also available, but it's preset frequencies are suited for the Japanese FM band (76-90Mhz).

As a footnote, LPFM transmitters are Legal Here, and in Aus on 2 bands... 88 - 88.5 , and 106.7 - 108 Mhz (the bands the BH1417 is preset to) using an ERP up to 0.5 watt (with Xtal stability)... which gives surprisingly good coverage... (most of the town I live in). As for Music Copyright, AMCOS/APRA/PPL offer a deal for non-profit LPFM transmitters of $200 a year. Obviously that FAQ pertains to my country, and legalities will be different where ever you are.

Thread Starter


Joined Jan 7, 2007
First of all the FBI is not the copyright police. It is a civil matter. It is the responsibilty of the copyright holder to take the offender to court.
Second, I must apologize, I did not explain my intentions. This is a project for a communications class. I am not mass producing them nor selling them. Merely building on a bread board to develop a better understanding.


Joined Jul 24, 2007
i am a guy who needs help to do with my scool's project... i need to develope a fm transmitter.. i already have a circuit scemathics but the problem is i dont understands which is which...could anybody plz help me with this design...i need to know stuff like which is the modulater... the filter and everything...plz help me... email me at help!!!!