Tunecast I broadcast distance. - Electronic Circuits Projects Diagrams Free

juan123 · 6th August 2006, 02:00 PM

I recently bought a Tunecast I(FM transmitter for mp3, ipod, etc) from Belkin, and it's ok. But even more recently I got a Tunecast II which is much better.

I'd like to make my Tunecast I's distance of transmission increase. How could I do this? I'd like to get it to be like 1/4 of a mile or more, if possible. Thanks for any assistance.

For those who don't know what a tunecast is, here's a link :
http://www.walmart.com/catalog/produ...uct_id=2569450

RadioRon · 6th August 2006, 06:28 PM

The most economical way to increase distance is to improve the transmitting antenna, but this will mean adding a large antenna that makes the thing no longer portable. The easiest thing to do would be to open up the product, find a way of coupling a transmission line into the circuit, then run that transmission line to a high point on a building, preferably higher than 20 feet, and attach it to a half wave dipole oriented vertically. Since transmission line eats your power, it is best to find a way to keep this transmission line short. For example, mounting the transmitter near the antenna and running a long audio feedline makes a lot of sense.

It is also possible to increase the transmitter power generated in the device, but this may be quite complicated and will eat more battery power, so I don't recommend it.

No matter what you do you will be exceeding the legal allowance for emission levels for such a device.

juan123 · 6th August 2006, 06:43 PM

Ok, I will add the antenna, but i'd like to do everything that's possible to get the max. range I can. I live in the outskirts, so breaking the FCC don't really matter... I don't care of portability either, bc I will be using this with a transformer... Thanks for any help!!

RadioRon · 6th August 2006, 10:44 PM

Quote:

Originally Posted by juan123

Ok, I will add the antenna, but i'd like to do everything that's possible to get the max. range I can. I live in the outskirts, so breaking the FCC don't really matter... I don't care of portability either, bc I will be using this with a transformer... Thanks for any help!!

Then you should be able to improve range substantially with a good antenna. You will be able to pick up at least 10 dB of improvement this way, and this can make a big difference in range. With these frequencies, the height of your antenna is critical, the higher the better, so go as high as you can, even if it means an extra wooden pole attached to a chimney, for example.

audioguru · 6th August 2006, 10:58 PM

The transmitter's RF output probably has an attenuator on it like this project has: http://electronics-diy.com/schematic...ransmitter.htm

Without the attenuator and with a good antenna its range might be 100 feet.
You need to remove the attenuator then add an RF power amplifier for a range of 1000 feet. Then replace the little battery every few minutes.

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6th August 2006, 02:00 PM	(permalink)
juan123	Tunecast I broadcast distance. I recently bought a Tunecast I(FM transmitter for mp3, ipod, etc) from Belkin, and it's ok. But even more recently I got a Tunecast II which is much better. I'd like to make my Tunecast I's distance of transmission increase. How could I do this? I'd like to get it to be like 1/4 of a mile or more, if possible. Thanks for any assistance. For those who don't know what a tunecast is, here's a link : http://www.walmart.com/catalog/produ...uct_id=2569450 __________________ Thanks! --Juan

6th August 2006, 06:28 PM	(permalink)
RadioRon	The most economical way to increase distance is to improve the transmitting antenna, but this will mean adding a large antenna that makes the thing no longer portable. The easiest thing to do would be to open up the product, find a way of coupling a transmission line into the circuit, then run that transmission line to a high point on a building, preferably higher than 20 feet, and attach it to a half wave dipole oriented vertically. Since transmission line eats your power, it is best to find a way to keep this transmission line short. For example, mounting the transmitter near the antenna and running a long audio feedline makes a lot of sense. It is also possible to increase the transmitter power generated in the device, but this may be quite complicated and will eat more battery power, so I don't recommend it. No matter what you do you will be exceeding the legal allowance for emission levels for such a device. __________________ RadioRon

6th August 2006, 06:43 PM	(permalink)
juan123	well... Ok, I will add the antenna, but i'd like to do everything that's possible to get the max. range I can. I live in the outskirts, so breaking the FCC don't really matter... I don't care of portability either, bc I will be using this with a transformer... Thanks for any help!! __________________ Thanks! --Juan

6th August 2006, 10:58 PM	(permalink)
audioguru	The transmitter's RF output probably has an attenuator on it like this project has: http://electronics-diy.com/schematic...ransmitter.htm Without the attenuator and with a good antenna its range might be 100 feet. You need to remove the attenuator then add an RF power amplifier for a range of 1000 feet. Then replace the little battery every few minutes. __________________ Uncle $crooge