Dragonlink LNA review - Part 1

Here's a short look at the Dragonlink 1.2 - 1.3 GHz LNA.  We'll measure it's frequency response/gain in various configurations.

I ordered a single unit with my own $ from fpvpro.com.  Non-affiliate link to the item here: Video Signal Amplifier ( LNA ) 1.2 - 1.3 GHZ.

Filters used for testing (non affiliate links):
    TBS 1.2GHz VRX Notch Filter (868/915 MHz)

    Minicircuits ZX75BP-1260-S+

The test setup:

The device under test:

Power consumption at the minimum and maximum input voltages:

VNA sweep, device off:

VNA sweep, device on:

TBS/VAS 1.2GHZ VRX notch filter (868/915 MHZ) before the LNA:

TBS/VAS 1.2GHZ VRX notch filter (868/915 MHZ) after the LNA:

  

Minicircuits ZX75BP-1260-S+ before the LNA:

Minicircuits ZX75BP-1260-S+ after the LNA:

This configuration should be the ideal one for both sensitivity (lowest overall system noise figure) and crossfire rejection, as long at the IP3 of the LNA isn't a limiting factor.  I'll do the IP3 measurement in another blog post. And for the sensitivity/noise figure, real world testing will be required to confirm.

Results: We see 48 dB of rejection at 915 MHz, and a very nice passband from 1.15 to 1.36 GHz with a gain of 13 dB.

Hope you enjoyed this.  Stay tuned for part 2...

~PK