Dave's Whole House FM MP3 Broadcaster
Wallwart PS, MP3 FM transmitter, remote & portable radio
People have said a few things about me over the years. First, that I am resourceful and can make something useful out of about anything. They also say that I am very cheap! This project has allowed me to combine my best talents, thinking and cheapness. My motto: Think Cheap!
Ok, now that you all have had your laugh at my expense, it is time for me to tell you about my latest project. I've been thinking about this for a month or so, but I finally was able to realize my dream earlier today.
The project is a whole house FM mp3 music and podcast broadcaster. That assumes you live in a small house as the range has to conform with the FCC (Funny Cigarette Company) rules.
List Of Parts Required
The main ingredient is a Made in China automotive FM transmitter / MP3 player. These are available starting at around $4 from eBay sellers in Hong Kong and mainland China. Spend some time on eBay looking for the unit you want. Some good search terms are MP3, Player, Car, FM Transmitter. As you search and find sale headings, you will find more ideas for searches. Most of these have remote controls. I like the ones that have F+ and F- on the remote as these allow you to move from folder to folder. Each folder can contain a complete cd or other file sorts. As I wrote, there are different options and different prices to choose from, so take your time. I already placed one of these in my car and now listen to my own cd's instead of the commercial laden radio. Besides the stations stopped playing big band tunes decades ago!
Next you will need a 12 volt dc wall wart power supply. Many of us have saved these long after the device it powered has met the landfill. You will need a 300mA or higher supply. Mine is a 500mA one. I wouldn't go higher than that as these supplies are not voltage regulated. A 1Amp power supply could have 16 or 17 volts under the 200mA load that one of these FM transmitters have. Also, stay away from battery charger only supplies as they are likely not to have any filtering.
You will need a female cigar lighter connector too. This is wired (observe polarity) to the wall wart output. The center pin on the lighter socket is the positive terminal. There are some Chinese sellers on eBay offering these sometimes for low prices. Search for Car Female Lighter Socket. One seller had 5 for 6 bucks. I used one that I had around, but plan on buying some of these as I know my friends and neighbors will want me to make systems for them.
These FM transmitters come without memory. You will need a USB stick, or SD or SD micro a.k.a. TF memory filled with your favorite files. I use 2GB SD-micro memory cards. The acutual type of memory varies with the FM transmitter selected. If you pick a non USB type of memory, make sure you have a reader that your computer understands. A 2GB memory can hold 300–500 tunes depending on the bit rates. Since these FM transmitters ease of selection leave a little to be desired, using smaller memory is a boon for finding the tunes you want. I use different cards for different genre's.
Finally you will need one or more nearby FM radios. I bought a nifty little DSP FM radio from a Chinese seller on eBay a few months ago. It runs on two AAA NiMh batteries and so far has not needed a charge. I still haven't purchased a AAA charger. When they need it, I'll pull apart one of my cordless phones and let the phone charge the batteries. Someday I'll buy a charger.
How To Use
There were no instructions with this FM transmitter, but they are pretty simple. Use the remote to select a vacant local FM channel. These transmitters tune every channel and then some.
Once you have the frequency set, tune in the carrier on your FM radio. You will need to rip your CD collection to your computer in the MP3 format. Some of these transmitters will also play WMA format, but I use MP3 for all my audio needs. Since the CD's are yours, you do have the right to move the format from a cd to other formats for playing on computer devices. This is called"fair use". Don't forget podcasts.
Take a look at my review of a cheap MP3 speaker player that I bought. Did I mention it was cheap?
One Last Thing …
I like buying this stuff directly from the Chinese. You don't see this stuff in most stores, and never at these prices. Most of our purchases will go very well and everything will work fine.
However occasionally there will be a glitch. Something will arrive late, or maybe something is broken. I never leave less than the full positive feedback. I refuse to beat up some poor Chinese guy for a $4 item. It just isn't my nature. Something can break in the mail,or whatever. If it is important enough, contact the seller.