Software defined radio LNR transceiver FX-4a *REVIEW*

Dear all,
I’ve tested for you the FX 4a transceiver. This is an excellent Software defined radio
Hereby a little review for you.


This new transceiver has been released few months ago and replaces the original Software defined radio FX-4 that was introduced in 2013. It’s quite impressive as transceiver because very light (345 gr) and tiny (dimensions: 4 in length  x 2.8 width x 1.5 thickness).

Ah yes, it arrived to me fully assembled (what a shame! – I LOVE TO BUILD my TRANSCEIVER!) – so no kit! The radio was delivered in a double carton and extremely well packed. 1 week to arrive to Europe.

This Software defined radio covers HF but only 4 bands (40 meters , 30 meters , 20 meters and 17 meters band)
True QRP: only 5W. Modes are SSB and CW.

Selectivity is quite sharp while calibration is excellent.
In reception I found the LNR transceiver FX-4a as an excellent SDR receiver: audio is clean and pleasant but AGC action is of low authority. Compared to my Elecraft KX3 signals were loud and more clean. Consider that on my KX3 I have installed the roof one.



Specifications of this Software defined radio LX4

  • Push to Talk Speaker Mic
  • Input Voltage Monitoring
  • RIT Functions
  • Independent Side Tone
  • Iambic Keyer
  • CW Call Feature
  • 5W Output
  • 10 Memory Storage per band
  • Microphone and Power Cord included!
  • 90 Day Warranty

Comparison with the FT 817 ND

I found the FT 817 more silent and I have to say the LNR FX-4a as more sensitive.
Dimensions are clearly in favor of the LNR transceiver. Please see down here the comparison:


The  Software defined radio SDR FX-4a is half size and also lighter than Yaesu FT 817. Also you may consider battery that are not included in the LNR precision transceiver. I suggest you to get a LIPO from RC model store like I did (3S 13.8V 2100 mAh for few bucks). I always like (and I will like) the audio from the speaker of my YAESU FT 817 ND because it’s louder than these two SDRs (Elecraft KX3 and LNR FX-4a). Reception : LNR FX-4a was clear and nice to hear but FT 817 was not so bad. I tried these two with a random wire antenna tossed into the tree in front of my house. I should maybe have tried this (LNR precision end-fed antenna)

Price is around 450$ (not so much).
Order can be done directly on the website LNR precision inc