Has anyone used this antenna?  Do you know if it is a sleeved dipole or if it is a linear antenna or something else?  Do you know how long it is?

Have you used it on your quad?  If so how did it perform long range?  (yes I know it says TX antenna, but in all but rare situations, an antenna is an antenna as long as the purpose is the same)

There is almost zero info on the TBS site and elsewhere.

https://www.getfpv.com/tbs-crossfire-tun...tenna.html

https://www.team-blacksheep.com/products...tx_antenna

Nobody here either....

I guess I will order one and put it on the analyzer.

If it is a good antenna, I will report on it.

When I get the TBS antenna, I will compare their antenna with my recent build.

With a VSWR of 1.114 and a SNR of 25.34, and nearly perfectly attenuated at 915mhz, they have their work cutout for them to keep up.

Yes I've seen them used on the diversity RX with a T on the arm and this at the rear to give full polorised spectrum

(30-Jan-2021, 02:20 AM)coyote_dc5 Wrote: Yes I've seen them used on the diversity RX with a T on the arm and this at the rear to give full polorised spectrum

How long are they?

FWIW I found this antenna on Amazon and they list the packaging as 10.5” long.  Also comes in a 90* version.  

https://www.heli-nation.com/team-blacksh...tx-antenna

(31-Jan-2021, 02:30 PM)lownslow Wrote: FWIW I found this antenna on Amazon and they list the packaging as 10.5” long.  Also comes in a 90* version.  

https://www.heli-nation.com/team-blacksh...tx-antenna

Thank you!

The bell of the SMA connector is likely 9mm if they used a typical one (looks like they did).  By my guess, around 140 and 150 mm.

(31-Jan-2021, 03:57 PM)kaitylynn Wrote: The bell of the SMA connector is likely 9mm if they used a typical one (looks like they did).  By my guess, around 140 and 150 mm.

One of the things I love about you Kaity, a very logical problem solver!

Thanks for your input!

(31-Jan-2021, 04:34 PM)Krohsis Wrote: One of the things I love about you Kaity, a very logical problem solver!

Thanks for your input!

LOL, or a super board housewife!  Not sure which

I am starting to like the single whip style antenna design.  Could envision that it would require similar orientation of the RX antennas (vertical<->vertical)?

There is almost zero info on this antenna.  I even wrote Trappy about it, but no answer.  He is pretty slow to respond.

Externally it looks like it could be a sleeve dipole.  But it could be a base loaded linear whip too.  


I bought one, and will test it against some other antennas.  If it tests well it might be a good choice for those who don't want to build their own.

I received this antenna from GetFPV yesterday and got a chance to test it.  My original plan was to dissect it, but it is a good enough antenna to keep in a flight box, I likely won't tear it apart.  So some things will remain a mystery like whether it is a sleeve dipole or a base loaded linear.  But I may change my mind.  If I do tear it apart I will post my findings in this thread.

One of the bigger issues with this antenna is if it is a sleeve dipole the location of the sleeve, at the bottom/SMA connection, defeats having a sleeve dipole.  This is because the sleeve, the passive element, is still below things like the battery which is a problem in overall performance.  If it is a linear, then no biggie for the most part, but a linear will not perform as well as a dipole for our uses.  You could build an elevated connection point, but that might look too weird.



The antenna length is right at 7 inches, or 178mm...so you were pretty close, Kaity.  






 For all you Anorexic quad builders it weighs in at 12grams.   And yes, I'm still in my comfy pants.....





As you can see, it is not a great antenna at 915mhz.  VSWR is out of spec, but more problematic is the SNR, pretty low.



There is good and bad in this antenna.  Like I expected, it is tuned in between 868mhz and 915mhz, resonating at 900mhz.  At 900mhz it is a very good antenna, the best TBS antenna I have tested.  So TBS can make a good antenna instead of the junk they call the Immortal T.  At either side of that at 868mhz and 915mhz, it is only a ho hum average to below average antenna as you can see below.  So by trying to make the antenna work for both, it really doesn't work well for either.  At greater distances is when this disparity will show its ugly head.



 
In the graph where the yellow triangle is, is where 915mhz is.  The bottom of the dip on the red line is the resonate point.

Maybe they should make two versions, one for each region, and then maybe it could really be considered tuned?

Lol...was off by an inch! Would make a joke about guesstimating sizes, but there are kids on the forums and I am outnumbered.

What if it is side mounted on both sides (port and starboard) with a diversity receiver?

I was really hoping this antenna worked good since it looks much more manageable to install and far more secure (from a gyro noise perspective) than trying to vertically mount an Immortal T.

(02-Feb-2021, 06:46 PM)the.ronin Wrote: What if it is side mounted on both sides (port and starboard) with a diversity receiver?

I was really hoping this antenna worked good since it looks much more manageable to install and far more secure (from a gyro noise perspective) than trying to vertically mount an Immortal T.

Actually, that is a great idea, Ronin.  There would still be some negative effects to each antenna just by being next to RF pestering items, but the effect should be minimal.  (I should do a video someday to show what I'm talking about)  But the really bad negatives would be alleviated with your idea.