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On 7/8/23 3:57 PM, Ma?l H?rz wrote: > Hello, > I have read various sources on the Internet and it seem that the classic > NanoVNA is best suited for testing filters (below 300 MHz) and measuring >

Hello, I have read various sources on the Internet and it seem that the classic NanoVNA is best suited for testing filters (below 300 MHz) and measuring crystals. It also seems that the DiLord

Yes, very much so There are two effects to be aware of: 1) if the signal is close to the test frequency, it makes it through the receiver. Broadcast FM is pretty wideband - the VNA's receiver is about

You reset calibration after change threshold? Old calibration contain bad data

Did it, but unfortunately it didn't work: same condition at 300MHz. Is really the SI5351 generator overheating? The problem appears even when the device is just switched on. Additional question: I

si5351 generator overheating and not stable work near top limit Need reduce threshold to 295MHz, save config, recalibrate This solve problems in 290-310MHz Others threholds - only fixed inside

Hi, I am sure that almost 3 months ago, when I measured my Log Periodic antenna Create-5130-1N, its SWR was almost perfectly flat in all the 50-1300 MHz range. However I am now seeing strong and

- working update methods for me: I have original devices, - I always like to use the STM32CubeProgrammer https://www.st.com/en/development-tools/stm32cubeprog.html One device (I think not important

Got the firmware update done this afternoon and it's working fine! Thanks again for the help! Tom AE5I

I have check Core Isolation and it is OFF. Many thanks. There are other driver that not permit activation of this protection. Thank you for help. -- 73 de Salvo IZ7VLL.

Thanks Alan, and thanks to everyone else for sharing your knowledge and experience. But now I must move on. The sun is shining and the coil is up in the air. I have optimised the antenna wire lengths

Maybe this will help... /g/tinysa/topic/97866810 Istvan

I have the same problem. Now I'm waiting for new one. I able to upgrade firmware but not to use vna with app on Windows 10 or Debian 12. -- 73 de Salvo IZ7VLL.

I should add, strap a bar or plate where the LC is located to get a sense of the fixture R. Back out that mesured loss to get Rs fixture. You can use that mesure to provide some correction.

In the same fixture, check the inserted 15 ohm only. The uniform loss should be ~ 8.5 dB. It is possible that not all the current with the LC inserted is passing via the inserted R. Since this is a

Hi Brian, Thank you for your explanations. That is what I love about this forum, I learn something every day. The coil length explanation is really interesting and makes sense given your explanation.

Bob, for a given number of turns, inductance decreases as the coil is lengthened due to lower coupling between turns. The optimizer maximizes Q while keeping inductance constant. It increased the

Actually foam, being mostly air, would be better. Another approach would be to drill many holes in the material, leaving a skeletal frame which, again, is mostly air. This is essentially what B&W does

Hi Alan I tried the experiment with a 15 ohm carbon resistor but it didn't produce the expected result. The calculated resistance went up from 7.5 ohm

Hi Brian, I do not pretend to be any sort of expert here, so I have probably missed something vital. But in your 2nd iteration, I notice the coil length is significantly longer (156.8mm vs 80mm) with