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problem with direction finding using IsoLOG

Hello Aaronia team,

it's about 1 week that I'm working on DF with IsoLOG 80, I use a very simple mission as upload  ("my_mission"). the configuration of blocks will be uploaded. I just sat the chopper mode to 1000 us and turned "auto rotate" option on, while every thing is stable, I see the arrow on the "directional finding block" flutter and heat map's red bin is 10 degrees away from the arrow.  after that I turn my IsoLOG antenna 360 clockwise and keep it fixed for 10 sec and after that move it back to its main position by turning 360 degrees counter clockwise. neither the arrow or the heat map followed my turning scenario. the video of screen is ready here: ( .

it may be noted that even if everything be fixed and stable, the arrow moves and flutter. any help would be appreciated


Uploaded files:
  • Direction_power_spectrum_Configuration.png
  • IsoLOG_Configuration.png
  • my_mission.PNG

Please check the latest mission/posting at

This should work rock solid if you DON'T change any settings (only IsoLOG IP and SPECTRAN V6 serial no).

We can't look at videos where you need to register, sorry.

najisamirnader has reacted to this post.

Thank you for forming a complete mission for me. I have 2 related questions:

First: I just do the mission as you mentioned but still there is a little oscillations in the arrow. (The arrow follows my rotation pattern but if I kepp it stable it is about 10 degrees fluttering ) I previously thought that it's accuracy is about 2 degrees. Can you explain how may I fix it?



And I have a second question: if I use a real signal instead of my own generated CW signal (I used my commerical remote working on 433 MHz) and I'm sure it is active for some milliseconds while it has enough SNR; the arrow doesn't follow my rotation pattern. What sort of reasons may influence this?

Simply follow the instruction. Depending on the signal you might need to rise it (BTW please note that 433MHz will not offer a super accurate DF since this is the absolut minimum frequency for DF. Use higher frequencies for a more accurate DF. Also be sure not to influence the DF by near objects e.g., your body):

The "Filter Direction" will help to get the directional arrow/line more stable. 5% should be a nice setting still keepeing the speed at real-time level:

Sofon and najisamirnader have reacted to this post.

thanks for the responsibility,

As you mentioned, I replaced the 433 MHz signal by the frequency of 2GHz and a pulse with period of 100ms and duty cycle of 50%.(I mean this pulse is active in 50ms and off for 50ms and so on...) the problem is that the arrow/line of the "directional finding" block doesn't work well.

I guess maybe it's because for the "off time" of the pulse, the arrow spins irregular and because of high pulse rate I can't distinguish that. If my guess is right, can you please tell me how may I distinguish the direction of a short pulse ?? (if the pulse disappear soon I can't follow the arrow)


Note: I've used both chopper mode "on" and "off" for this mission; but no one solved the problem.

You may need to increase the time compression for pulsed signals:


In RSA 250X, can I use Tx as the third Rx3 (receiver)? I want to have 3 E-filed components then use IsoLOG for the direction finding. Would that work?





This has nothing to do with this thread, plase start a new topic.