Sorry not audio related but thought some of you guys would know.
I have a wi fi extender with four on pcb internal antennas
But the signal I am getting from the free WiFi area beach is marginal. I am thinking of making a diy yagi antenna to boost the signal by about 10db but do I connect it to any internal antenna on the pcb?
I have a wi fi extender with four on pcb internal antennas
But the signal I am getting from the free WiFi area beach is marginal. I am thinking of making a diy yagi antenna to boost the signal by about 10db but do I connect it to any internal antenna on the pcb?
Unless you can tap into a point that matches the 50 ohm coax feeding your antenna, you may loose more signal than your antenna can get you due to impedance mismatch.
Best are the units with detachable antennae...that you can work with.
There are many articles about "coffee can antennae" for wifi on the net and some of them may address the impedance mismatch issue.
Have fun.
Best are the units with detachable antennae...that you can work with.
There are many articles about "coffee can antennae" for wifi on the net and some of them may address the impedance mismatch issue.
Have fun.
At these frequencies anything with length can be an inductor and anything with area can be a capacitor.
And your impedance matching may require a couple of each.
I don't even consider trying this modification an option.
If you had a unit with a detachable antenna...
I use one of these, after reading many good reviews....
Alfa AWUS036H Upgraded to 1000mW 1W 802.11b/g High Gain USB Wireless Long-Rang WiFi network Adapter with 5dBi Antenna - for Wardriving & Range Extension: Amazon.co.uk: Computers & Accessories
I have a DIY cantenna which is directional, and a +9db omni antenna.
It's only b+g but this is rarely an issue if you're trying to connect to free public wifi.
I'm sure this would work well with a yagi. I got best results using no rf cable and directly connecting the unit to the cantenna using a coax termination adapter (can't remember the exact type). A long USB cable (with active extender if required) is less of an issue than a lossy coax.
If you search google you can find out how to increase the tx power beyond normal levels. It's a simple process, although you might accidentally exceed legal limits in your region. I obviously haven't done that, but believe the benefits can be significant.
Please show us your solution when you've finished the project.
Alfa AWUS036H Upgraded to 1000mW 1W 802.11b/g High Gain USB Wireless Long-Rang WiFi network Adapter with 5dBi Antenna - for Wardriving & Range Extension: Amazon.co.uk: Computers & Accessories
I have a DIY cantenna which is directional, and a +9db omni antenna.
It's only b+g but this is rarely an issue if you're trying to connect to free public wifi.
I'm sure this would work well with a yagi. I got best results using no rf cable and directly connecting the unit to the cantenna using a coax termination adapter (can't remember the exact type). A long USB cable (with active extender if required) is less of an issue than a lossy coax.
If you search google you can find out how to increase the tx power beyond normal levels. It's a simple process, although you might accidentally exceed legal limits in your region. I obviously haven't done that, but believe the benefits can be significant.
Please show us your solution when you've finished the project.
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I've had good success with a parabolic reflector screen, although it won't work easily with the device in your picture.
The parabolic thing is much easier to build than a cantenna or a yagi. Probably much less effective, but it literally takes 20 minutes to give it a try: all you need is some paper where you print the proper pattern and some aluminum foil. Search on internet for "parabolic wifi reflector".
But the antenna must be in the focus point, not easy to do in your setup.
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The parabolic thing is much easier to build than a cantenna or a yagi. Probably much less effective, but it literally takes 20 minutes to give it a try: all you need is some paper where you print the proper pattern and some aluminum foil. Search on internet for "parabolic wifi reflector".
But the antenna must be in the focus point, not easy to do in your setup.
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yagi design online:
Online Calculator .:. Yagi Uda Antenna
(not really so simple)
The other thing about Rf (besides the "anything with length can be an inductor and anything with area can be a capacitor") is that with inductance and capacitance come a characteristic impedance.
And if the characteristic impedance is not utilized correctly you can end up with an RF short circuit at a point that can measure open circuit with an ohmmeter.
The Circuit Designer had to match the impedance of the antennae to the transmitting and receiving devices. There might not be a point where the impedance matching networks transformed to a point where you can tap in with a 50ohm (or other) load.
You might not affect the circuit at all. Which is OK for the circuit but you will not be extracting any power to transmit with.
Or you may detune the existing circuit to either present a higher impedance load to the transmitting device and not get any power for transmitting or present a lower impedance and blow up the transmitting device.
Just sayin.
Online Calculator .:. Yagi Uda Antenna
(not really so simple)
The other thing about Rf (besides the "anything with length can be an inductor and anything with area can be a capacitor") is that with inductance and capacitance come a characteristic impedance.
And if the characteristic impedance is not utilized correctly you can end up with an RF short circuit at a point that can measure open circuit with an ohmmeter.
The Circuit Designer had to match the impedance of the antennae to the transmitting and receiving devices. There might not be a point where the impedance matching networks transformed to a point where you can tap in with a 50ohm (or other) load.
You might not affect the circuit at all. Which is OK for the circuit but you will not be extracting any power to transmit with.
Or you may detune the existing circuit to either present a higher impedance load to the transmitting device and not get any power for transmitting or present a lower impedance and blow up the transmitting device.
Just sayin.
Yagi Smagi, go for a transmission line or a coplanar. The TL can yield >30dBi gain and the coplanars can do upwards of 20dBi and are easy to make out of quality RG6. Never use foam core, only solid polypropylene or if you have the $$$ teflon. Velocity factor is far better with these types.
Luv'n my GH4N3 w/ tophats
Luv'n my GH4N3 w/ tophats
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Actually the yagi is the easiest to construct like this one here
High Gain Yagi Wi-Fi Antenna
And I only need like 10 db. As it is I need to stick the extender right on my balcony edge which is ugly otherwise it cannot connect inside the house. With the antenna the extender can stay inside.
High Gain Yagi Wi-Fi Antenna
And I only need like 10 db. As it is I need to stick the extender right on my balcony edge which is ugly otherwise it cannot connect inside the house. With the antenna the extender can stay inside.
Can't you get another WiFi adapter that has a detachable antenna?
That Yagi looks like more work to build than a Pringles can antenna, and some other designs which can be found in the classic "Wireless Hacks: 100 Industrial-Strength Tips & Tools", published by O'Reilly. Searching for "Wireless_Hacks_-_100_Industrial-Strength_Tips_Tools_2003.chm" might be fruitful.
That Yagi looks like more work to build than a Pringles can antenna, and some other designs which can be found in the classic "Wireless Hacks: 100 Industrial-Strength Tips & Tools", published by O'Reilly. Searching for "Wireless_Hacks_-_100_Industrial-Strength_Tips_Tools_2003.chm" might be fruitful.
That's easier that a coplanar?! How hard is it to cut'n trim coax, solder these links together and be done? Unlike a yagi that must be pointed at the source vs coplanars that are omni and vertically oriented. Need directionality? Add a wire mesh paraboloid reflector that doesn't have to be perfect for greater directionality and or interference rejection. Stick it in a corner out of the way and without getting wierd looks or poked in the eye.
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