www.webx.dk Start page

MY little Radio Control page

Please also see the Video OSD, On Screen Display page

LNA low noise amplifier for 2.4GHz

The LNA open, see more: inside 1 - inside 2 - inside 3

Datasheet over the LNA:
http://www.rfbayinc.com/LNA/LNA-2425.pdf if this site is down or moved use this : lna2425-datasheet.pdf

The 3 pin device size SOT-89 with number 2GW is from Avago ATF52189 it is narrow band matched to improve the NF beyond device spec 1.6dB

Real facts measured in lab:
1600MHz Gain=10.0dB NF=0.98 RTNIN=-3 RTNOUT=-11
2300MHz Gain=15.0dB NF=0.84 RTNIN=-8 RTNOUT=-16
2400MHz Gain=15.1dB NF=0.66 RTNIN=-14 RTNOUT=-19
2500MHz Gain=14.6dB NF=0.54 RTNIN=-11 RTNOUT=-20
2600MHz Gain=13.1dB NF=0.63 RTNIN=-6 RTNOUT=-12
2700MHz Gain=11.0dB NF=0.99 RTNIN=-4 RTNOUT=-8

Isolation in-out at power off = 10dB,
Isolation out-in at power on = 20dB

At 500Mhz there is still 6dB gain left, so I think I maybe need a hi pass filter.

It does improve range at super weak levels you can now fly longer away with less TX power,
how much improvement is up to your RX type, but I see improvement on all the types I have on stock.
On a Comtech receiver the antenna signal can be 4dB weaker for same TV picture
same result will be achived if your 500mW TX was upgraded to 1.2W ! By using LNA to achive this you get a lighter plane,
and save power on the plane, and you also prevent possible interfering and jamming of sensitive electronics on your plane.

I mounted the LNA and powersupply from Intelligent Flight on a 33 x 90 mm alu plate
The male-male SMA adaptor is used so the LNA fit directly on my RX, the input of the LNA go directly to my Patch antenna

Note the extra little plate mounted UNDER the powersuppy is to heatsink it.
I have mounted a tiny SMD LED and resistor on top of one of the capacitors, indicating power on.
This great little powersupply can generate 3.3V 5V 9V or 12V easyly selected with a solder joint.

Thomas Scherrer OZ2CPU August 2007