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Gebbinn
01-22-2011, 11:43 PM
I was at Goodwill today, just poking around through the shelves... I love that place... when I came across this neat looking little toy. It was only $3.99 so I figured I would buy it and tear it down to see what I can see.

Now, I am not exactly what you would call an expert, in fact, most novices would probably make my head spin, but I want to give this a try. SO, I will be tearing this apart, asking questions, taking and posting pictures and so on and so forth. Hopefully this will turn into something useful, if not, I will learn something and I am only out 4 bucks.

So, because the pics are huge, I am only going to post links for you. once I figure out a good way to reduce them in size I will include the pics in the posts.

This is the toy I bought. (http://i261.photobucket.com/albums/ii50/Gebbinn/IMAG0011.jpg)

This is the back of the unit. (http://i261.photobucket.com/albums/ii50/Gebbinn/IMAG0021.jpg)

probably should have done this first, but here is a page I found that explains this stuff more than I could. Apparently this is an AM transmitter, putting out on 1610AM, with a reasonable range out to about 300'

http://www.part15.us/node/694

IdunBenhad
01-23-2011, 08:46 AM
Hi:
That is an interesting toy. If you decide to use it for your display, I think you will be the first to use AM.

Also on that site you found is a PC card for FM, but it's pricey. $177 for a 100 mw unit.

Put your pics into a photo editor, like Paint Shop Pro and reduce the size. There are other ways, which I'm sure the guys will tell us about.

Gebbinn
01-23-2011, 12:44 PM
Ok, after spending a few hours playing around with this, I stumbled across the fact that there is a DOT transmitter in my area transmitting road conditions for the mountain passes ( I live just west of White Pass ski area in Washington ) that transmits on, you guessed it, 1610AM. Leave it to the gubment to mess up a fun possibility. So, unfortunately, this project is now scrapped. Sorry to waste your time.

IdunBenhad
01-23-2011, 01:28 PM
Hi:
Just for your information, that 1610 khz frequency has been used for many, many years as an Information Radio Station. I installed several in Colorado in the 1970's.

Their range is limited, as is your device. Unless you live within a few hundred feet of White Pass, you shouldn't have any problem. However, they probably use a big antenna, usually a vertical that is about 5 to 10 feet long, which will increase their range.

griffixdc
01-23-2011, 02:37 PM
Hi:
Just for your information, that 1610 khz frequency has been used for many, many years as an Information Radio Station. I installed several in Colorado in the 1970's.

Their range is limited, as is your device. Unless you live within a few hundred feet of White Pass, you shouldn't have any problem. However, they probably use a big antenna, usually a vertical that is about 5 to 10 feet long, which will increase their range.

there you go bet a BIGGER antenna and you will be fine ....make it big though like REAL BIG

tstraub
01-23-2011, 02:45 PM
I would suggest not trying to overpower someone else's signal. If you want to pursue this protect swap out the crystal to change the transmitting frequency.

Tyler

Gebbinn
01-23-2011, 02:50 PM
yeah, the problem, and why I scrapped the project, is because I am within 1500' of the broadcast antenna that the DOT is using, and this little toy cannot overpower the signal even 20' away from the radio. So, it was fun while it lasted, and I still have something to play with. I am using it to desolder and resolder to get some practice before I get started building my boards for the display.

griffixdc
01-23-2011, 02:50 PM
I would suggest not trying to overpower someone else's signal. If you want to pursue this protect swap out the crystal to change the transmitting frequency.

Tyler

yes your right if you broadcast too strong it is illegal....good idea with crystal...is that what selects the frequency...i thought it was resistors that filter the frequency to be selected...although i might be getting mixed up with sound not transmission.

tstraub
01-23-2011, 03:03 PM
Yes. The crystal frequency divided by 4 sets the carrier frequency. Although this option is probably more of just a project for fun. Walmart sells Fm transmitters for $12 that would suit his needs just as well. So no money savings in this project.

Tyler

DaveJZ
01-24-2011, 05:53 PM
I agree with a few others... about scrapping the project, However that is a good idea you have to use it to work on soldering...

griffixdc
01-25-2011, 12:07 AM
Yes. The crystal frequency divided by 4 sets the carrier frequency. Although this option is probably more of just a project for fun. Walmart sells Fm transmitters for $12 that would suit his needs just as well. So no money savings in this project.

Tyler
would you by chance know what model number this transmitter is ..i went to walmart and every transmitter costs about 40 or more:(

tstraub
01-25-2011, 06:29 AM
The transmitter I was referring to is a Scosche FMT-4R (http://www.walmart.com/ip/Scosche-FM-Transmitter/14666784)
Look in the car audio section at your local Walmart
Also see this http://doityourselfchristmas.com/forums/showthread.php?14327-Scosche-FMT4RA-Hack-Mod
tYLER

Gebbinn
01-27-2011, 04:05 AM
Well, I did it again. this time I got a FM transmitter. Interesting looking unit. called a Cellected (http://www.cell-phone-accessories.com/celbranporfm.html) hands free device. More info will be upcoming, but I picked this up at Goodwill, still in the box, with the plastic covering still on the digital readout. I only paid 1.99 for this one. Lets see how it turns out. Pics will come when I get a chance to play with it.

DaveJZ
01-27-2011, 01:15 PM
This looks to be closer to what most are saying walmart has. I think for 1.99 you can't beat it.

IdunBenhad
01-27-2011, 02:01 PM
Hi:
One thing the blurb didn't mention. Is it stereo? If it's for a cell phone, probably not.