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High gain antenna
- magic_marty
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Later on i am going to get into FPV and want to increase my signal strength as much as possible..Thought about trying one of these but have no idea if it would work www.radioddity.com/us/sh24bta-n-2500mw-2...m-wifi-repeater.html read on another forum of people using them with great success but not sure if it would work with the Devo8 without causing some problems or damaging the TX..So i thought if i can find a higher gain antenna it would work hopefully...
thanks all..
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- syphear
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- Hexperience
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Have you looked at these?
www.hobbyking.com/hobbyking/store/__2010...Radios_Modules_.html
I'd be interested to see what kind of range we get with this antenna, 150mw setting and an RX802...
There are 10 types of people in this world. Those that understand binary and those that don't.
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- vlad_vy
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- Hexperience
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By the way, the devo8 comes with a 2db and the devo12 is a 5db right?
There are 10 types of people in this world. Those that understand binary and those that don't.
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- RandMental
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vlad_vy wrote: 5 dB difference with original Devo 8 antenna = 1.778 power increase = 1.33 range increase, with very narrow directional diagram.
The implication of the very narrow directional pattern Vlad mention is important. What you gain in the optimal direction, you lose in other directions.
So unless you take care to ensure your TX antenna is kept perpendicular to the line of sight to your model, you may find that you are suddenly out of range if you move the TX.
Moral of the story? Don't use a higher gain antenna if you don't need it!
.
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- magic_marty
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Hexperience wrote: Interesting device, needs power though so you need to use a battery or build a ground station.
Have you looked at these?
www.hobbyking.com/hobbyking/store/__2010...Radios_Modules_.html
I'd be interested to see what kind of range we get with this antenna, 150mw setting and an RX802...
Yes it requires separate power source so i was thinking if i go that route i could just power it off the balance plug on tx lipo..its still a long way off before i get into any FPV but i like to look ahead and plan things out long before i attempt them.Plus the cost of all the equipment adds up so i have to go little by little but will eventually get there.Hopefully
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- vlad_vy
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- RandMental
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I am suspect of the nice clean "3dBi" statement of the 12s in these tests over the 2.4GHz band, compare this to the different gains of the Devo8s antenna over the 2.4GHz band.
As you clearly understand RF and antennas, you will agree the higher the gain figure of an antenna of the same size / configuration, the narrower the gain pattern AND the gain bandwidth.
So my guess is these 3dBi figures on the 12s test sheet are the theoretical figures, and they forgot to update it after the tests as they did for the Devo8.
Edit: if these antenna figures are indeed true, I would agree that one should replace the Devo8 antenna with a Devo12 antenna, as the Devo8 emitted power drops to 54% at the top for the band (2.479GHz).
.
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- vlad_vy
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- cmpang
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vlad_vy wrote: Possible both antennas, Devo 8s and Devo 12s are the same, I don't see any visual difference between them.
things ain't that bad as you might think.
when the model is near by, the power it gets is quite strong and so a bit out of the main radiation lobe doesn't matter..
while it flies out at distance, the angle of deviation it departed from the main lobe gets smaller and smaller...
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- RandMental
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cmpang wrote:
vlad_vy wrote: Possible both antennas, Devo 8s and Devo 12s are the same, I don't see any visual difference between them.
things ain't that bad as you might think.
when the model is near by, the power it gets is quite strong and so a bit out of the main radiation lobe doesn't matter..
while it flies out at distance, the angle of deviation it departed from the main lobe gets smaller and smaller...
Hi cmpang, your are of course 100% correct, provided you don't point and shoot (fly), which is of course the worst scenario, especially the with the Dev07E's fixed antenna. Anyhow my concern was more the reduction in emitted power on the Devo8 at the higher end of the band.
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- Hexperience
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vlad_vy wrote: Possible both antennas, Devo 8s and Devo 12s are the same, I don't see any visual difference between them.
This is what came with my devo 8 and 12 so I assume they are the same internally
There are 10 types of people in this world. Those that understand binary and those that don't.
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- RandMental
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Interestingly your 12S antenna looks like the ones I received with both my 8s Devos. I added two external antennas (like the smaller one on you photo) for the XL7105 and CC2500 modules. By switching the longer and shorter antennas around I do notice a lower output from the smaller antenna, my guess is not even 2dBm.
Here a few other antenna samples, the first is the short antenna taken apart, as expected it is a normal dipole configuration:
The Devo7e standard antenna:
Home build version for a 7105 module placed inside the Devo7e using RG74 coax cable:
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- magic_marty
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- R/C Madman68
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It's a 3dbi. I bought my 8s used and the antenna that was on it was not only the wrong one it had female to female so no contact. I used a gold pin from a wifi antenna repair kit and inserted it to get proper connection but in the back of my mind I think it is not 100% GTG!
Antenna
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- victzh
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- R/C Madman68
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- Block137
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Could that damaged the module already?R/C Madman68 wrote: I know this is a old thread but wanted to know if this would make for a good stock replacement antenna?
It's a 3dbi. I bought my 8s used and the antenna that was on it was not only the wrong one it had female to female so no contact.......
Antenna
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- victzh
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