Antenna

the following youtoube video

bluetooth Device". Right now, both devices stop talking to each other when I walk carrying the "bluetooth device" more than 25 to 30 feet away from my laptop.

with this 50 ohm Jack. I am trying to increase the range of the bluetooth dongle. If this is true then what type and dimension of the antenna should I use.

connection, if I walk away form the laptop more than 25 to 30 feet.

What range do you need? Are you really "walking around" or can you use a fixed location with directional antennas?

When you can, put the bigger antenna at the fixed location, not the mobile one. Both is better.

Most youtube videos are put up by people who haven't a clue.

It's possible that you lose more in impedance mismatch than you gain from the external antenna...assuming you didn't short the connection or leave the shield disconnected.

For fixed paths, the usual thing is to use a usb extension cord and put the dongle at the focus of a parabola or inside a cantenna. Google "war driving" for tips. Sometimes merely relocating the dongle on the extension cable can get you a few more feet.

the following youtoube video

bluetooth Device". Right now, both devices stop talking to each other when I walk carrying the "bluetooth device" more than 25 to 30 feet away from my laptop.

with this 50 ohm Jack. I am trying to increase the range of the bluetooth dongle. If this is true then what type and dimension of the antenna should I use.

connection, if I walk away form the laptop more than 25 to 30 feet.

These people love to answer such questions:

You need an antenna for 2.4GHZ-2.48GHZ. Check the wiki.

Cheers

Adding a new antenna may not help you much. Commercial antennas are designed for a 50 ohm impedance. The impedance matching on a Bluetooth board rarely matches the 50 ohm spec. In fact its often closer to 20 ohms. This is deliberate to limit range by using a barely radiating antenna to meet the FCC and International standards for a intentional radiator. It is also what allows Bluetooth users to share spectrum space the way they do.

Steve

the following youtoube video

bluetooth Device". Right now, both devices stop talking to each other when I walk carrying the "bluetooth device" more than 25 to 30 feet away from my laptop.

with this 50 ohm Jack. I am trying to increase the range of the bluetooth dongle. If this is true then what type and dimension of the antenna should I use.

connection, if I walk away form the laptop more than 25 to 30 feet.

Hi John

You need a hill (maintain line-of-sight) and these antennas. Go for it - break the record ;-)

July 30th, 2004, New World Record for Bluetooth Link!:

Quote: "... The test: Connect to a low-power Bluetooth cellphone from a distance of

1 kilometer

The result: Success! ..."

/Glenn

This seems unlikely. Have a look at the application notes for any of the widely used BT chips. You will find plenty of detail on optimising the matching to a 50 Ohm antenna.

John