Author Topic: NanoVNA H4 attenuator reading jumping  (Read 156 times)

0 Members and 1 Guest are viewing this topic.

Offline u666saTopic starter

  • Frequent Contributor
  • **
  • Posts: 408
  • Country: ru
NanoVNA H4 attenuator reading jumping
« on: November 16, 2024, 09:28:01 am »
I have NanoVNA H4, with SD card, version 4.3, bought it from here, it's the real thing, not fake. Firmware as from Hugen 1.2.27, I upgraded it to DiSlord 1.2.40, behavior did not change.

Basically, after calibration, when two cables connected together, I'm measuring -759 umdB to 515 umdB (and prior to firmware upgrade it was showing 0 dB to -0 dB).

Then I insert 20 dB 25W attenuator, and I'm getting values jumping like so..... -20.55 dB, -20.54 dB, -20.56 dB. It stays mostly on -20.55 dB.
Then I insert 30 dB 2W attenuator, -30.05 dB, -30.02 dB, -30.01 dB, -30.03 dB, -30.04 dB.

What's going on? What's up with jumping?

Then, if I decide to use these attenuators in TinySA Ultra to measure power, I also have power jumping. For example TID-RADIO H3 is jumping from 5.5 watts all the way to 6.1 watts.  |O
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf