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How to open 3dBi 900MHz for SWR fine tuning ?


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#1 Jacky65

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Posted 08 October 2008 - 09:18 PM

Hi all,
Is it possible to open this 3dBi 900MHz from Rangevideo antenna for SWR fine tuning ?
I have 4 samples and range is different with two of them.
Thanks in advance

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#2 Mr.RC-Cam

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Posted 08 October 2008 - 09:27 PM

It is weakly glued at the base and can be wiggled apart. However, the Hyperlink antenna is not just a piece of wire that would be easily trimmed. Once inside, you will find that it is a coaxial design that uses big diameter metal tubing for the dipole elements. Trimming or extending them will be interesting.

I would be very surprised if you found that the good antenna had different element lengths from the bad one. Are you sure there isn't something else going on that is causing the difference in performance? For example, maybe your Rx's SMA jack has a worn/damaged center pin and the two mates are not making good contact. Or some other goofy thing like that.
- Thomas

#3 Jacky65

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Posted 08 October 2008 - 11:00 PM

It is weakly glued at the base and can be wiggled apart. However, the Hyperlink antenna is not just a piece of wire that would be easily trimmed. Once inside, you will find that it is a coaxial design that uses big diameter metal tubing for the dipole elements. Trimming or extending them will be interesting.

I would be very surprised if you found that the good antenna had different element lengths from the bad one. Are you sure there isn't something else going on that is causing the difference in performance? For example, maybe your Rx's SMA jack has a worn/damaged center pin and the two mates are not making good contact. Or some other goofy thing like that.



Hi Mr.RC-Cam,
Thanks for your feedback, it will be very helpful for me.
Best Regards,
Jacky65

#4 Terry

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Posted 08 October 2008 - 11:01 PM

What test gear do you have ?

Terry

#5 Jacky65

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Posted 09 October 2008 - 12:40 AM

What test gear do you have ?

Terry


Hi Terry,
I have a receiver AOR AR-3000-A.
I just look the signal meter of the receiver to compare antennas.
I know it should be better to connect a SWR-meter but I don't have one.

#6 Terry

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Posted 09 October 2008 - 03:11 AM

If you take it out to the middle of a field you should be able to get usable readings.
Good luck.

Terry

#7 Jacky65

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Posted 13 October 2008 - 10:10 PM

Hi
Below a picture of the opened antenna.
Somebody know how to change the frequency from 910MHz (860-960MHz) to 1040MHz (channel 4) ?
Thanks in advance
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