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Old Apr 22, 2015, 11:11 PM
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Quote:
Originally Posted by Cathay Stray View Post
Interesting then what the ideal width would be given very thin and flat cross section...
Ad absurdum the biquad can be just pinholes in the middle of solid squares, on the opposite the width can be equal to the wire's diameter. Either way would perhaps not be the best...
It depends on the frequency, but my guess is that ~2-3mm thick on 1.3Ghz would do well. For 2.4GHz 1-2mm should work. Don't make the elements too thick or it won't work correctly.

-Alex
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Old Apr 22, 2015, 11:36 PM
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Quote:
Originally Posted by IBCrazy View Post
~2-3mm thick on 1.3Ghz would do well
Thickness is a constant value with copper laminated board
I can only take width as a variable.
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Old May 18, 2015, 06:33 PM
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Just saw this thread and going to build a BiQ for my 2.4GHz control Tx tonight!
One question - the cable I have is RG58 AU and the impedance is apparently 53.2ohm. Will I have a problem with mismatch and high SWR? I'm planning to use 16AWG copper wire for the driven and copper clad board for reflector.
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Old May 20, 2015, 08:27 PM
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Quote:
Originally Posted by elewon View Post
Just saw this thread and going to build a BiQ for my 2.4GHz control Tx tonight!
One question - the cable I have is RG58 AU and the impedance is apparently 53.2ohm. Will I have a problem with mismatch and high SWR? I'm planning to use 16AWG copper wire for the driven and copper clad board for reflector.
You should be ok. I used RG58/u for many 2.4GHz antennas.

-Alex
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Old May 20, 2015, 11:29 PM
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Alex, thanks. I went ahead and built it. Haven't had a chance to range test it yet but same range as the stock bazooka dipole has been confirmed.
Change of plans though and I bet this is the cheapest BiQ ever! The driven is two paper clips (~1mm thick) bent to shape and soldered. The reflector is aluminum foil taped over a piece of foam board. Used pieces of coffee stirrer hot glued for support. Will share the build pictures if I'm happy with the results.
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Old May 28, 2015, 01:04 AM
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So the Bi Quad seems to be working, don't know how well tuned it is though. Seems like Tx battery is draining faster but I'm definitely getting better range. Did a range check with the Tx on the ground and it's around 1100ft. Is that reasonable for LOS with 2.4G Tx, 17dbm power?

The other test was at the bluff where I go sloping. I'd get like 100ft with the stock antenna. Don't know if it was due to low power or multipaths but I was getting way short a range at that location. So right after take off, the control would get intermittent and really scary. Very happy that the receiver performs much better with BiQ on the Tx. Had a blast flying my wing for over 15mins with really smooth control.

Awesome and thanks again for sharing!
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Old Jun 02, 2015, 04:46 PM
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Quote:
Originally Posted by elewon View Post
So the Bi Quad seems to be working, don't know how well tuned it is though. Seems like Tx battery is draining faster but I'm definitely getting better range. Did a range check with the Tx on the ground and it's around 1100ft. Is that reasonable for LOS with 2.4G Tx, 17dbm power?

The other test was at the bluff where I go sloping. I'd get like 100ft with the stock antenna. Don't know if it was due to low power or multipaths but I was getting way short a range at that location. So right after take off, the control would get intermittent and really scary. Very happy that the receiver performs much better with BiQ on the Tx. Had a blast flying my wing for over 15mins with really smooth control.

Awesome and thanks again for sharing!
Sounds to me like it is tuned well enough. Great to see an ultra cheap DIY unit working well.

-Alex
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